1000+ MLT MCQs with Answers | Medical Laboratory Technology Exam Preparation

Singh_Parveen

2 months ago

Medical Laboratory Technology (MLT) exams are highly competitive, requiring students to have a deep understanding of multiple subjects including Hematology, Biochemistry, Microbiology, Histopathology, Blood Banking, and Quality Control. Practicing Multiple Choice Questions (MCQs) with detailed answers and explanations is one of the best ways to prepare for these exams. This page provides a comprehensive collection of 1000+ MLT MCQs with answers, organized subject-wise for effective preparation.

Introduction to MLT MCQs

Importance of MCQs in MLT exam preparation
How MCQs improve conceptual clarity
Why practice is key to ranking higher

Hematology MCQs with Answers

Red Blood Cell (RBC) Physiology & Disorders
White Blood Cell (WBC) Morphology & Disorders
Platelets & Coagulation Disorders
Hemoglobin Estimation Methods
Hematology Instruments & Automation

Clinical Biochemistry MCQs with Answers

Carbohydrate Metabolism & Diabetes Tests
Renal Function Tests (RFTs)
Liver Function Tests (LFTs)
Lipid Profile
Enzymes & Hormones
Electrolyte & Acid-Base Balance

Microbiology MCQs with Answers

Bacteriology (Gram-positive & Gram-negative bacteria)
Virology (RNA & DNA Viruses)
Mycology (Fungal Infections)
Parasitology (Protozoa & Helminths)
Sterilization & Disinfection Techniques
Culture Media & Techniques

Histopathology & Cytopathology MCQs with Answers

Tissue Fixation & Processing
Staining Techniques
Cytology Basics
Special Stains
Histopathology Instruments

Blood Bank & Immunohematology MCQs with Answers

Blood Group Systems
Crossmatching & Compatibility Testing
Rh Typing & Antibody Screening
Coombs Test
Blood Component Preparation
Quality Control in Blood Banking

Laboratory Techniques & Quality Control MCQs

Microscopy
Spectrophotometry
Chromatography & Electrophoresis
Automation in Laboratories
Quality Assurance & Control
Laboratory Safety

Miscellaneous MLT MCQs

Body Fluids (CSF, Urine, Stool)
Toxicology Tests
Molecular Biology in MLT
Recent Advances in Laboratory Technology

🌟 Why Choose Our MLT MCQs?

✅ 1000+ Exam-focused questions with answers
✅ Covers Hematology, Biochemistry, Microbiology, Histopathology, Blood Bank, and QC
✅ Designed for quick revision before exams
✅ Helpful for B.Sc MLT, DMLT, and competitive exams

🩸 MLT MCQs – Hematology

Q1. Which organ is the primary site of hematopoiesis in adults?
a) Liver
b) Spleen
c) Bone marrow
d) Thymus
Answer: c) Bone marrow
Explanation: In adults, bone marrow is the main site; liver and spleen are fetal hematopoietic organs.

Q2. Which is the first cell in erythropoiesis lineage?
a) Myeloblast
b) Proerythroblast
c) Normoblast
d) Reticulocyte
Answer: b) Proerythroblast
Explanation: Erythropoiesis begins with proerythroblast → basophilic normoblast → orthochromatic normoblast → reticulocyte → RBC.

Q3. Average life span of RBC is:
a) 60 days
b) 90 days
c) 120 days
d) 150 days
Answer: c) 120 days
Explanation: Normal life span = 120 days, then destroyed in spleen.

Q4. Which organ is called the “graveyard of RBCs”?
a) Liver
b) Spleen
c) Kidney
d) Bone marrow
Answer: b) Spleen
Explanation: Spleen removes old, defective RBCs.

Q5. Hemoglobin synthesis requires all EXCEPT:
a) Iron
b) Vitamin B12
c) Globin protein
d) Protoporphyrin
Answer: b) Vitamin B12
Explanation: Vitamin B12 is for DNA synthesis; hemoglobin synthesis needs iron, protoporphyrin, globin chains.

Q6. Normal hemoglobin in adult males is:
a) 9–11 g/dL
b) 12–14 g/dL
c) 13–17 g/dL
d) 18–20 g/dL
Answer: c) 13–17 g/dL

Q7. The commonest type of anemia worldwide is:
a) Megaloblastic anemia
b) Iron deficiency anemia
c) Hemolytic anemia
d) Aplastic anemia
Answer: b) Iron deficiency anemia

Q8. In iron deficiency anemia, RBCs appear:
a) Normocytic normochromic
b) Macrocytic normochromic
c) Microcytic hypochromic
d) Macrocytic hyperchromic
Answer: c) Microcytic hypochromic

Q9. Pernicious anemia is caused by deficiency of:
a) Iron
b) Vitamin C
c) Vitamin B12
d) Folic acid
Answer: c) Vitamin B12

Q10. Which stain is used to demonstrate iron in bone marrow?
a) Wright’s stain
b) Giemsa stain
c) Prussian blue stain
d) Hematoxylin & Eosin
Answer: c) Prussian blue stain

Q11. Normal total leukocyte count (TLC) in adults:
a) 1,000–3,000 /µL
b) 4,000–11,000 /µL
c) 15,000–20,000 /µL
d) 20,000–50,000 /µL
Answer: b) 4,000–11,000 /µL

Q12. The predominant WBC in peripheral blood is:
a) Lymphocyte
b) Monocyte
c) Neutrophil
d) Eosinophil
Answer: c) Neutrophil

Q13. “Philadelphia chromosome” is associated with:
a) AML
b) CML
c) ALL
d) CLL
Answer: b) CML

Q14. Which leukemia is most common in children?
a) ALL
b) AML
c) CML
d) CLL
Answer: a) ALL

Q15. Which WBC shows “Auer rods” in cytoplasm?
a) Lymphoblast
b) Monoblast
c) Myeloblast
d) Plasma cell
Answer: c) Myeloblast

Q16. Normal platelet count:
a) 50,000–100,000/µL
b) 100,000–200,000/µL
c) 150,000–400,000/µL
d) 400,000–600,000/µL
Answer: c) 150,000–400,000/µL

Q17. Deficiency of factor VIII causes:
a) Hemophilia A
b) Hemophilia B
c) Von Willebrand disease
d) DIC
Answer: a) Hemophilia A

Q18. Which test evaluates intrinsic coagulation pathway?
a) PT (Prothrombin Time)
b) APTT (Activated Partial Thromboplastin Time)
c) Bleeding time
d) Clotting time
Answer: b) APTT

Q19. Prothrombin time is prolonged in:
a) Hemophilia A
b) Vitamin K deficiency
c) Thrombocytopenia
d) Von Willebrand disease
Answer: b) Vitamin K deficiency

Q20. Platelet function is assessed by:
a) PT
b) APTT
c) Bleeding time
d) ESR
Answer: c) Bleeding time

Q21. ESR is measured by:
a) Wintrobe tube
b) Neubauer chamber
c) Sahli’s tube
d) Coagulometer
Answer: a) Wintrobe tube

Q22. The principle of Sahli’s hemoglobinometer is:
a) Cyanmethemoglobin method
b) Acid hematin method
c) Spectrophotometry
d) Colorimetry
Answer: b) Acid hematin method

Q23. Neubauer chamber is used for:
a) Hemoglobin estimation
b) WBC and RBC counting
c) ESR
d) Platelet aggregation test
Answer: b) WBC and RBC counting

Q24. Reticulocytes are stained by:
a) Leishman’s stain
b) Wright’s stain
c) Supravital stains
d) H&E
Answer: c) Supravital stains (e.g., new methylene blue)

Q25. Heinz bodies are demonstrated by:
a) Romanowsky stains
b) Supravital stains
c) Prussian blue stain
d) Periodic Acid Schiff
Answer: b) Supravital stains

Q26. The universal donor blood group is:
a) AB+
b) O–
c) AB–
d) O+
Answer: b) O–

Q27. The universal recipient blood group is:
a) O–
b) O+
c) AB+
d) A+
Answer: c) AB+

Q28. Rh typing is based on:
a) D antigen
b) C antigen
c) E antigen
d) All of the above
Answer: a) D antigen

Q29. Hemolytic disease of newborn occurs due to:
a) ABO incompatibility
b) Rh incompatibility
c) Both
d) None
Answer: b) Rh incompatibility

Q30. Crossmatching is done to detect:
a) Antibody in donor
b) Antibody in recipient
c) Clotting disorder
d) Platelet defect
Answer: b) Antibody in recipient

Q31. The diagnostic stage of malaria in peripheral smear is:
a) Schizont
b) Gametocyte
c) Trophozoite
d) All of the above
Answer: d) All of the above

Q32. Which stain is used for malaria parasite?
a) Leishman’s stain
b) Field’s stain
c) Giemsa stain
d) All of the above
Answer: d) All of the above

Q33. Which species of Plasmodium causes malignant malaria?
a) P. vivax
b) P. malariae
c) P. falciparum
d) P. ovale
Answer: c) P. falciparum

Q34. Microfilaria is best detected in:
a) Early morning blood
b) Daytime blood
c) Urine
d) Bone marrow
Answer: a) Early morning blood

Q35. Babesia infection is transmitted by:
a) Tsetse fly
b) Ixodes tick
c) Sandfly
d) Anopheles mosquito
Answer: b) Ixodes tick

Q36. The anticoagulant used for CBC is:
a) Citrate
b) Heparin
c) EDTA
d) Oxalate
Answer: c) EDTA

Q37. Which anticoagulant is used for coagulation studies?
a) EDTA
b) Heparin
c) Sodium citrate
d) Potassium oxalate
Answer: c) Sodium citrate

Q38. MCV is calculated as:
a) (Hematocrit × 10) / RBC count
b) (Hemoglobin × 10) / RBC count
c) (Hemoglobin × 100) / Hematocrit
d) (RBC × 100) / Hematocrit
Answer: a) (Hematocrit × 10) / RBC count

Q39. Normal reticulocyte count in adults is:
a) 0.2–1%
b) 0.5–1.5%
c) 2–4%
d) 5–7%
Answer: b) 0.5–1.5%

Q40. ESR increases in all EXCEPT:
a) Anemia
b) Tuberculosis
c) Pregnancy
d) Polycythemia
Answer: d) Polycythemia

Q41. Principle of flow cytometer is:
a) Coulter principle
b) Light scattering & fluorescence
c) Colorimetry
d) Nephelometry
Answer: b) Light scattering & fluorescence

Q42. Principle of electronic cell counter (Coulter counter):
a) Impedance (electrical resistance)
b) Light scattering
c) Nephelometry
d) Spectrophotometry
Answer: a) Impedance (electrical resistance)

Q43. Hemoglobin estimation in automated analyzers is usually done by:
a) Acid hematin method
b) Cyanmethemoglobin method
c) Sahli’s method
d) Direct spectrophotometry
Answer: b) Cyanmethemoglobin method

Q44. In capillary electrophoresis of Hb, HbS moves:
a) Faster than HbA
b) Slower than HbA
c) Same as HbA
d) Not detected
Answer: b) Slower than HbA

Q45. ESR by automated method uses principle of:
a) Capillary photometry
b) Impedance
c) Nephelometry
d) Flow cytometry
Answer: a) Capillary photometry

Q46. Rouleaux formation of RBCs is typically seen in:
a) Malaria
b) Multiple myeloma
c) Iron deficiency anemia
d) Hemophilia
Answer: b) Multiple myeloma

Q47. Target cells are seen in:
a) Thalassemia
b) Iron deficiency anemia
c) Aplastic anemia
d) Hemophilia
Answer: a) Thalassemia

Q48. Sickle cells are best seen in which preparation?
a) Wright’s stain
b) Leishman’s stain
c) Supravital stain
d) Wet preparation
Answer: d) Wet preparation

Q49. G6PD deficiency causes:
a) Megaloblastic anemia
b) Hemolytic anemia
c) Aplastic anemia
d) Hypochromic anemia
Answer: b) Hemolytic anemia

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Q50. In hereditary spherocytosis, RBC osmotic fragility is:
a) Decreased
b) Increased
c) Normal
d) Variable
Answer: b) Increased

51. Which anticoagulant is used for CBC in automated hematology analyzers?
a) Heparin
b) Sodium citrate
c) EDTA (K₂EDTA or K₃EDTA)
d) Oxalate

✅ Answer: c) EDTA (K₂EDTA or K₃EDTA)
Explanation: EDTA prevents clotting by chelating calcium and preserves cell morphology, making it ideal for CBC.

52. What is the normal reference range of hemoglobin in adult males?
a) 10–12 g/dL
b) 12–14 g/dL
c) 13–17 g/dL
d) 18–20 g/dL

✅ Answer: c) 13–17 g/dL
Explanation: Adult male Hb range is slightly higher due to testosterone effect.

53. Which of the following is NOT a red cell inclusion?

a) Howell–Jolly body
b) Heinz body
c) Pappenheimer body
d) Döhle body

✅ Answer: d) Döhle body
Explanation: Döhle bodies are found in neutrophils, not RBCs.

54. Reticulocyte count is best stained by which method?
a) Romanowsky stain
b) Supravital stain (New methylene blue)
c) Wright stain
d) PAS stain

✅ Answer: b) Supravital stain
Explanation: Reticulocytes require supravital stains like New methylene blue or Brilliant cresyl blue.

55. Which condition shows target cells (codocytes)?
a) Iron deficiency anemia
b) Thalassemia
c) Sickle cell anemia
d) All of the above

✅ Answer: d) All of the above
Explanation: Target cells occur in thalassemia, liver disease, iron deficiency, and hemoglobinopathies.

56. Which is the normal reticulocyte percentage in adults?
a) 0–1%
b) 0.5–1.5%
c) 2–3%
d) 3–5%

✅ Answer: b) 0.5–1.5%
Explanation: Reticulocyte count reflects bone marrow activity.

57. Which test is used to confirm paroxysmal nocturnal hemoglobinuria (PNH)?
a) Ham’s test
b) Sucrose hemolysis test
c) Flow cytometry for CD55/CD59
d) All of the above

✅ Answer: d) All of the above
Explanation: Older tests include Ham’s and sucrose lysis; gold standard is flow cytometry.

58. Heinz bodies are composed of:
a) Iron granules
b) Denatured hemoglobin
c) Nuclear remnants
d) RNA aggregates

✅ Answer: b) Denatured hemoglobin
Explanation: Heinz bodies are seen in G6PD deficiency and unstable hemoglobin disorders.

59. Which anemia is associated with glossitis and neuropathy?
a) Iron deficiency anemia
b) Megaloblastic anemia
c) Hemolytic anemia
d) Aplastic anemia

✅ Answer: b) Megaloblastic anemia
Explanation: Due to vitamin B12 deficiency, causing neurological symptoms.

60. Normal mean corpuscular volume (MCV) range is:
a) 50–70 fL
b) 80–100 fL
c) 110–130 fL
d) 70–90 fL

✅ Answer: b) 80–100 fL
Explanation: MCV <80 = microcytosis, >100 = macrocytosis.

61. Which stain is used for bone marrow iron stores?
a) PAS
b) Perls’ Prussian blue
c) Sudan black B
d) Wright stain

✅ Answer: b) Perls’ Prussian blue
Explanation: Detects ferric iron deposits in bone marrow.

62. What is the normal ESR (Westergren) in adult males?
a) 0–5 mm/hr
b) 0–15 mm/hr
c) 0–20 mm/hr
d) 0–30 mm/hr

✅ Answer: b) 0–15 mm/hr
Explanation: ESR is higher in females (up to 20 mm/hr).

63. Which hemoglobin is predominant in newborns
a) HbA
b) HbA₂
c) HbF
d) HbS

✅ Answer: c) HbF
Explanation: HbF (α₂γ₂) is predominant in fetal and neonatal period.

64. Which anticoagulant is used for coagulation studies?
a) EDTA
b) Sodium fluoride
c) Sodium citrate
d) Lithium heparin

✅ Answer: c) Sodium citrate
Explanation: Citrate binds calcium reversibly and preserves clotting factors.

65. Which test is the screening test for sickle cell disease?
a) Coombs test
b) Solubility test (Sickling test)
c) Osmotic fragility test
d) Ham’s test

✅ Answer: b) Solubility test (Sickling test)
Explanation: Confirmatory test is hemoglobin electrophoresis or HPLC.

66. Howell–Jolly bodies are composed of:
a) DNA remnants
b) RNA remnants
c) Iron granules
d) Denatured Hb

✅ Answer: a) DNA remnants
Explanation: Seen in post-splenectomy, megaloblastic anemia.

Which RBC index is calculated as Hb × 10 / RBC count?
a) MCV
b) MCH
c) MCHC
d) RDW

✅ Answer: b) MCH
Explanation: Mean corpuscular hemoglobin = Hb (g/dL) × 10 ÷ RBC (millions/µL).

The Philadelphia chromosome is associated with:
a) AML
b) CML
c) ALL
d) CLL

✅ Answer: b) CML
Explanation: t(9;22) → BCR-ABL fusion gene is hallmark of CML.

Which is the normal WBC count in adults?
a) 2000–4000 /µL
b) 4000–11,000 /µL
c) 12,000–20,000 /µL
d) 1000–2000 /µL

✅ Answer: b) 4000–11,000 /µL
Explanation: Leukocytosis >11,000/µL, leukopenia <4000/µL.

Basophilic stippling of RBCs is seen in:
a) Iron deficiency anemia
b) Lead poisoning
c) G6PD deficiency
d) Sickle cell anemia

✅ Answer: b) Lead poisoning
Explanation: Coarse basophilic stippling = lead poisoning, thalassemia.

The normal platelet count is:
a) 50,000–1,00,000/µL
b) 1–1.5 lakhs/µL
c) 1.5–4 lakhs/µL
d) 5–10 lakhs/µL

✅ Answer: c) 1.5–4 lakhs/µL
Explanation: Thrombocytopenia <1.5 lakh, thrombocytosis >4 lakh.

Rouleaux formation is seen in:
a) Thalassemia
b) Multiple myeloma
c) Iron deficiency anemia
d) Polycythemia

✅ Answer: b) Multiple myeloma
Explanation: Due to increased plasma proteins causing RBC stacking.

Which test is used to diagnose G6PD deficiency?
a) Fluorescent spot test
b) Coombs test
c) Sickling test
d) ESR

✅ Answer: a) Fluorescent spot test
Explanation: Detects NADPH fluorescence; absence indicates deficiency.

Coombs test detects:
a) Free plasma hemoglobin
b) RBC-bound antibodies
c) Serum ferritin
d) Platelet antibodies

✅ Answer: b) RBC-bound antibodies
Explanation: Direct Coombs = antibody bound to RBC; Indirect Coombs = free antibodies in serum.

Spherocytes are typically seen in:
a) Thalassemia
b) Hereditary spherocytosis
c) Aplastic anemia
d) Sickle cell anemia

✅ Answer: b) Hereditary spherocytosis
Explanation: Spherocytes also occur in autoimmune hemolytic anemia.

Which vitamin deficiency causes megaloblastic anemia with neurological symptoms?
a) Folate
b) Vitamin B12
c) Vitamin K
d) Vitamin C

✅ Answer: b) Vitamin B12
Explanation: Folate deficiency does not cause neuropathy, B12 does.

Echinocytes (burr cells) are associated with:
a) Uremia
b) Thalassemia
c) Lead poisoning
d) G6PD deficiency

✅ Answer: a) Uremia
Explanation: Burr cells are seen in renal disease.

The osmotic fragility test is increased in:
a) Sickle cell anemia
b) Thalassemia
c) Hereditary spherocytosis
d) Iron deficiency anemia

✅ Answer: c) Hereditary spherocytosis
Explanation: Spherocytes rupture early in hypotonic saline.

Which of the following hemoglobins is NOT normally present in adults?
a) HbA
b) HbA₂
c) HbF
d) HbS

✅ Answer: d) HbS
Explanation: HbS is abnormal sickle hemoglobin.

What is the normal hemoglobin range in adult females?
a) 9–11 g/dL
b) 11–13 g/dL
c) 12–15 g/dL
d) 14–18 g/dL

✅ Answer: c) 12–15 g/dL
Explanation: Slightly lower than adult males.

Myeloblasts are positive for which cytochemical stain?
a) Sudan Black B
b) PAS
c) MPO (Myeloperoxidase)
d) Both a & c

✅ Answer: d) Both a & c
Explanation: Myeloid lineage cells are MPO and Sudan Black positive.

The hallmark of aplastic anemia is:
a) Pancytopenia with empty marrow
b) Macrocytosis
c) Target cells
d) Rouleaux formation

✅ Answer: a) Pancytopenia with empty marrow
Explanation: Bone marrow is hypocellular with fat replacement.

In iron deficiency anemia, serum ferritin is:
a) Increased
b) Normal
c) Decreased
d) Variable

✅ Answer: c) Decreased
Explanation: Ferritin reflects iron stores and is low in IDA.

The characteristic WBC finding in infectious mononucleosis is:
a) Neutrophilia
b) Reactive lymphocytes
c) Auer rods
d) Smudge cells

✅ Answer: b) Reactive lymphocytes
Explanation: Seen in EBV infection.

Which RBC abnormality is pathognomonic for G6PD deficiency during hemolysis?
a) Target cells
b) Spherocytes
c) Heinz bodies and bite cells
d) Schistocytes

✅ Answer: c) Heinz bodies and bite cells
Explanation: Oxidative stress damages Hb, producing Heinz bodies removed by spleen (bite cells).

The ESR is increased in all EXCEPT:
a) Pregnancy
b) Infections
c) Multiple myeloma
d) Polycythemia

✅ Answer: d) Polycythemia
Explanation: High RBC count lowers ESR.

The hallmark finding in multiple myeloma blood smear is:
a) Rouleaux formation
b) Target cells
c) Basophilic stippling
d) Auer rods

✅ Answer: a) Rouleaux formation
Explanation: Due to increased Ig production.

Which cell is known as the “smudge cell”?
a) Plasma cell
b) Lymphocyte in CLL
c) Neutrophil
d) Monocyte

✅ Answer: b) Lymphocyte in CLL
Explanation: Fragile lymphocytes break during smear preparation.

Which stain demonstrates glycogen in leukemic cells?
a) MPO
b) PAS
c) Sudan Black
d) Giemsa

✅ Answer: b) PAS
Explanation: PAS positivity helps in lymphoid leukemias.

Reed–Sternberg cells are diagnostic of:
a) AML
b) ALL
c) Hodgkin lymphoma
d) Non-Hodgkin lymphoma

✅ Answer: c) Hodgkin lymphoma
Explanation: RS cells are binucleate “owl’s eye” cells.

The normal RBC lifespan is:
a) 60 days
b) 90 days
c) 120 days
d) 150 days

✅ Answer: c) 120 days
Explanation: Normal RBC lifespan before being removed by spleen.

Schistocytes are typically seen in:
a) Aplastic anemia
b) Microangiopathic hemolytic anemia
c) Iron deficiency anemia
d) Megaloblastic anemia

✅ Answer: b) Microangiopathic hemolytic anemia
Explanation: RBC fragmentation due to intravascular hemolysis.

Auer rods are composed of:
a) DNA
b) RNA
c) Myeloperoxidase + lysosomal granules
d) Iron

✅ Answer: c) Myeloperoxidase + lysosomal granules
Explanation: Seen in AML (esp. M2, M3).

The “hairy cell” is positive for which cytochemical stain?
a) TRAP (Tartrate-resistant acid phosphatase)
b) PAS
c) MPO
d) Sudan Black

✅ Answer: a) TRAP
Explanation: Hairy cell leukemia is TRAP positive.

In sickle cell disease, sickling occurs due to:
a) HbF increase
b) HbS polymerization under low O₂
c) Iron overload
d) DNA mutation in spectrin

✅ Answer: b) HbS polymerization under low O₂
Explanation: Deoxygenated HbS polymerizes and distorts RBC shape.

Which RBC index indicates hypochromia when decreased?
a) MCV
b) MCH
c) MCHC
d) RDW

✅ Answer: c) MCHC
Explanation: MCHC ↓ = hypochromia.

Smudge cells are characteristic of:
a) AML
b) CML
c) CLL
d) ALL

✅ Answer: c) CLL
Explanation: Fragile lymphocytes seen in CLL.

Which coagulation factor is deficient in Hemophilia A?
a) Factor VIII
b) Factor IX
c) Factor XI
d) Factor XIII

✅ Answer: a) Factor VIII
Explanation: Hemophilia A = Factor VIII deficiency; Hemophilia B = Factor IX.

Which coagulation test monitors heparin therapy?
a) PT
b) aPTT
c) Bleeding time
d) Thrombin time

✅ Answer: b) aPTT
Explanation: Heparin prolongs aPTT.

Which coagulation test monitors warfarin therapy?
a) PT/INR
b) aPTT
c) Bleeding time
d) Clotting time

✅ Answer: a) PT/INR
Explanation: Warfarin prolongs PT/INR by inhibiting vitamin K–dependent factors.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Which of the following is used as an anticoagulant in ESR (Westergren method)?
a) Heparin
b) EDTA
c) Sodium citrate ✅
d) Potassium oxalate
👉 Explanation: ESR (Westergren) requires sodium citrate (3.8%), ratio 4:1 blood to anticoagulant.
Which anticoagulant is best for CBC (Complete Blood Count)?
a) Heparin
b) EDTA ✅
c) Sodium citrate
d) Sodium fluoride
👉 Explanation: EDTA (K₂ or K₃ EDTA) preserves cell morphology, used for hematology tests.
Heparin prevents clotting by inhibiting:
a) Calcium
b) Thrombin ✅
c) Fibrinogen
d) Platelet aggregation
👉 Explanation: Heparin activates antithrombin III → inhibits thrombin & Factor Xa.
The normal ESR value for males (Westergren method):
a) 0–5 mm/hr
b) 0–10 mm/hr ✅
c) 0–15 mm/hr
d) 0–20 mm/hr
👉 Explanation: Males: 0–10 mm/hr; Females: 0–20 mm/hr.
Increased ESR is seen in all except:
a) Tuberculosis
b) Pregnancy
c) Polycythemia vera ✅
d) Rheumatoid arthritis
👉 Explanation: ESR is low in polycythemia due to high RBC mass.
Which of the following is a microcytic hypochromic anemia?
a) Iron deficiency anemia ✅
b) Aplastic anemia
c) Megaloblastic anemia
d) Hemolytic anemia
👉 Explanation: Iron deficiency → ↓ Hb, small RBCs → microcytic hypochromic.
Megaloblastic anemia is caused due to deficiency of:
a) Vitamin C
b) Vitamin B₁₂ / Folic acid ✅
c) Iron
d) Vitamin K
👉 Explanation: B₁₂ & folate deficiency → impaired DNA synthesis → large RBCs (macrocytes).
The confirmatory test for sickle cell anemia is:
a) Solubility test
b) Electrophoresis ✅
c) Sickling test
d) Osmotic fragility test
👉 Explanation: Hb electrophoresis confirms HbS presence.
In hereditary spherocytosis, the osmotic fragility is:
a) Increased ✅
b) Decreased
c) Normal
d) Variable
👉 Explanation: Spherocytes rupture easily in hypotonic solutions → ↑ fragility.
Target cells are seen in:
a) Thalassemia ✅
b) Hereditary spherocytosis
c) Leukemia
d) Hemophilia
👉 Explanation: Target cells = excess membrane surface area; seen in thalassemia, liver disease.
Howell–Jolly bodies are:
a) Iron granules
b) DNA remnants ✅
c) RNA remnants
d) Nuclear fragments (lipid)
👉 Explanation: Howell–Jolly bodies = nuclear DNA remnants in RBCs, seen post-splenectomy.
Heinz bodies are:
a) RNA remnants
b) Denatured hemoglobin ✅
c) DNA fragments
d) Lipid deposits
👉 Explanation: Heinz bodies = denatured Hb, seen in G6PD deficiency, unstable hemoglobin.
Basophilic stippling of RBCs is seen in:
a) Lead poisoning ✅
b) Vitamin B₁₂ deficiency
c) Aplastic anemia
d) Malaria
👉 Explanation: Basophilic stippling = RNA remnants → characteristic of lead poisoning.
Rouleaux formation is most commonly seen in:
a) Multiple myeloma ✅
b) Hemophilia
c) Iron deficiency anemia
d) Sickle cell anemia
👉 Explanation: High plasma proteins cause stacking of RBCs → rouleaux.
The normal platelet count is:
a) 50,000–100,000/µL
b) 100,000–150,000/µL
c) 150,000–400,000/µL ✅
d) 400,000–600,000/µL
👉 Explanation: Normal platelet count = 150,000–400,000/µL.
Bleeding time is prolonged in:
a) Hemophilia
b) Thrombocytopenia ✅
c) Vitamin K deficiency
d) Liver disease
👉 Explanation: BT is prolonged in platelet disorders, not clotting factor deficiencies.
Clotting time is prolonged in deficiency of:
a) Factor VIII ✅
b) Platelets
c) Von Willebrand factor
d) Thromboxane A₂
👉 Explanation: Factor VIII deficiency (hemophilia A) prolongs clotting time.
The normal Prothrombin Time (PT) is:
a) 5–10 sec
b) 11–14 sec ✅
c) 20–30 sec
d) 30–60 sec
👉 Explanation: PT = 11–14 sec, evaluates extrinsic & common pathways.
Which factor is not Vitamin K dependent?
a) Factor II
b) Factor VII
c) Factor VIII ✅
d) Factor X
👉 Explanation: Vitamin K–dependent = II, VII, IX, X. Factor VIII is not.
The screening test for Hemophilia A is:
a) Bleeding time
b) Clotting time
c) Activated Partial Thromboplastin Time (APTT) ✅
d) Prothrombin time
👉 Explanation: Hemophilia A (Factor VIII deficiency) prolongs APTT (intrinsic pathway).
Reticulocyte count is useful in:
a) Leukemia
b) Assessment of bone marrow activity ✅
c) Clotting disorders
d) Platelet function
👉 Explanation: Reticulocyte % indicates marrow response to anemia.
Reticulocytes are stained using:
a) Leishman stain
b) New Methylene Blue ✅
c) Wright’s stain
d) Sudan black B
👉 Explanation: Reticulocytes are stained supravitally with new methylene blue.
The stain used for bone marrow iron is:
a) Leishman stain
b) Prussian blue ✅
c) Sudan black B
d) PAS
👉 Explanation: Iron granules in marrow detected by Perls’ Prussian blue stain.
Sudan Black B stain is used to identify:
a) Glycogen
b) Lipids ✅
c) Hemoglobin
d) Nucleic acids
👉 Explanation: Sudan Black B stains lipids, useful for myeloid leukemia diagnosis.
PAS stain is positive in:
a) Acute lymphoblastic leukemia (ALL) ✅
b) AML
c) Iron deficiency anemia
d) Hemophilia
👉 Explanation: PAS (Periodic Acid–Schiff) → positive in ALL (lymphoblasts).
Which of the following is NOT a cause of microcytosis?
a) Iron deficiency
b) Thalassemia
c) Lead poisoning
d) Vitamin B₁₂ deficiency ✅
👉 Explanation: B₁₂ deficiency → macrocytic, not microcytic anemia.
Which anemia is normocytic normochromic?
a) Iron deficiency
b) Aplastic anemia ✅
c) Thalassemia
d) Megaloblastic anemia
👉 Explanation: Aplastic anemia → reduced production, cells remain normocytic normochromic.
The earliest indicator of iron deficiency anemia is:
a) Serum ferritin ↓ ✅
b) Serum iron ↓
c) MCV ↓
d) Hemoglobin ↓
👉 Explanation: Ferritin (storage iron) falls first in iron deficiency.
Serum haptoglobin is decreased in:
a) Iron deficiency
b) Hemolytic anemia ✅
c) Megaloblastic anemia
d) Aplastic anemia
👉 Explanation: Free Hb from hemolysis binds haptoglobin → ↓ levels in hemolysis.
Which anemia shows hypersegmented neutrophils?
a) Iron deficiency
b) Megaloblastic anemia ✅
c) Aplastic anemia
d) Thalassemia
👉 Explanation: Hypersegmented neutrophils are classical in megaloblastic anemia.
The Philadelphia chromosome is seen in:
a) AML
b) CML ✅
c) ALL
d) CLL
👉 Explanation: t(9;22) → BCR-ABL fusion → Chronic Myeloid Leukemia.
Auer rods are seen in:
a) ALL
b) AML ✅
c) CLL
d) CML
👉 Explanation: Auer rods = myeloperoxidase-positive inclusions in AML blasts.
Reed–Sternberg cells are diagnostic of:
a) Multiple myeloma
b) Hodgkin lymphoma ✅
c) Non-Hodgkin lymphoma
d) CLL
👉 Explanation: RS cells (giant binucleate) are diagnostic for Hodgkin’s disease.
Smudge cells are seen in:
a) CML
b) AML
c) CLL ✅
d) ALL
👉 Explanation: Fragile lymphocytes in CLL → smudge cells.
Bence–Jones proteins are found in urine in:
a) Hemophilia
b) Multiple myeloma ✅
c) CML
d) Hodgkin lymphoma
👉 Explanation: Free light chains (Bence–Jones proteins) in MM urine.
The most common leukemia in children is:
a) AML
b) ALL ✅
c) CML
d) CLL
👉 Explanation: ALL is the most common childhood leukemia.
The most common leukemia in adults is:
a) CML
b) AML ✅
c) CLL
d) ALL
👉 Explanation: AML is the most common acute leukemia in adults.
CLL is most common in:
a) Children
b) Young adults
c) Elderly ✅
d) Middle-aged
👉 Explanation: Chronic Lymphocytic Leukemia is commonest in >60 years age.
The characteristic triad of multiple myeloma includes all EXCEPT:
a) Bone pain
b) Anemia
c) Thrombocytosis ✅
d) Bence–Jones proteinuria
👉 Explanation: MM triad = bone pain, anemia, renal dysfunction (not thrombocytosis).
Rouleaux formation is typically associated with:
a) Iron deficiency
b) Multiple myeloma ✅
c) Spherocytosis
d) Thalassemia
👉 Explanation: Excess plasma proteins (Ig) in MM → rouleaux.
Which RBC index is calculated as Hb × 10 / RBC count?
a) MCV
b) MCH ✅
c) MCHC
d) RDW
👉 Explanation: MCH (mean corpuscular hemoglobin) = Hb × 10 / RBC count.
MCHC is calculated as:
a) Hb × 10 / Hct ✅
b) Hb / RBC count
c) Hct × 10 / Hb
d) RBC × 10 / Hb
👉 Explanation: MCHC = Hb × 100 / Hematocrit (%).
RDW indicates:
a) RBC size variation ✅
b) RBC shape
c) Hemoglobin content
d) Platelet volume
👉 Explanation: RDW (Red Cell Distribution Width) → anisocytosis measure.
The anticoagulant used in coagulation studies is:
a) EDTA
b) Heparin
c) Sodium citrate ✅
d) Potassium oxalate
👉 Explanation: Sodium citrate (3.2%) is used for PT, APTT, coagulation assays.
Coombs’ test detects:
a) Platelet defects
b) Antibodies on RBCs ✅
c) Iron deficiency
d) Vitamin K deficiency
👉 Explanation: Direct Coombs detects antibodies bound to RBC surface.
Direct Coombs test is used in:
a) Hemophilia
b) Autoimmune hemolytic anemia ✅
c) Iron deficiency anemia
d) Polycythemia
👉 Explanation: DCT confirms immune-mediated RBC destruction.
Indirect Coombs test is used in:
a) Cross matching ✅
b) Hemophilia
c) Iron deficiency anemia
d) ESR estimation
👉 Explanation: ICT detects free antibodies in patient serum → used in transfusion crossmatch.
Bombay blood group lacks:
a) A antigen
b) B antigen
c) H antigen ✅
d) Rh antigen
👉 Explanation: Bombay phenotype (Oh) lacks H antigen → cannot form A/B antigens.
The universal blood donor (RBCs) is:
a) AB+
b) O– ✅
c) AB–
d) O+
👉 Explanation: O– RBCs lack A, B, Rh antigens → universal donor for RBC transfusion.
The universal blood recipient is:
a) O–
b) AB+ ✅
c) AB–
d) O+
👉 Explanation: AB+ has A, B, and Rh antigens → can receive from all groups.
The most common cause of iron deficiency anemia worldwide is:
a) Chronic kidney disease
b) Chronic blood loss ✅
c) Vitamin B12 deficiency
d) Thalassemia
Explanation: Chronic blood loss (e.g., GI bleeding) is the leading cause of iron deficiency anemia.
The most specific test for iron deficiency anemia is:
a) Serum iron
b) Serum ferritin ✅
c) Total iron-binding capacity
d) Transferrin saturation
Explanation: Serum ferritin reflects iron stores and is the most specific test.
In megaloblastic anemia, peripheral smear shows:
a) Microcytosis
b) Macro-ovalocytes and hypersegmented neutrophils ✅
c) Sickle cells
d) Target cells
Explanation: Megaloblastic anemia → impaired DNA synthesis → macrocytes and hypersegmented neutrophils.
Reticulocyte count is increased in:
a) Aplastic anemia
b) Hemolytic anemia ✅
c) Megaloblastic anemia
d) Iron deficiency anemia
Explanation: Hemolytic anemia → bone marrow responds by increasing reticulocytes.
Osmotic fragility test is used in the diagnosis of:
a) Thalassemia
b) Sickle cell anemia
c) Hereditary spherocytosis ✅
d) Aplastic anemia
Explanation: Spherocytes are more fragile in hypotonic solutions → increased osmotic fragility.
A patient with sickle cell anemia usually shows which abnormal hemoglobin on electrophoresis?
a) HbA
b) HbS ✅
c) HbF
d) HbC
Explanation: HbS is the abnormal hemoglobin responsible for sickling.
The confirmatory test for sickle cell disease is:
a) Solubility test
b) Hemoglobin electrophoresis ✅
c) Sickling test
d) Osmotic fragility test
Explanation: Electrophoresis distinguishes HbS from other hemoglobins.
Hemoglobin H disease is seen in:
a) β-thalassemia major
b) β-thalassemia minor
c) α-thalassemia (3 gene deletion) ✅
d) Sickle cell trait
Explanation: Loss of three α-globin genes → HbH (β₄ tetramers) formation.
Bone marrow in aplastic anemia is:
a) Hypercellular
b) Hypocellular ✅
c) Normocellular
d) Filled with blast cells
Explanation: Aplastic anemia → pancytopenia with hypocellular marrow.
Heinz bodies are seen in:
a) G6PD deficiency ✅
b) Aplastic anemia
c) Iron deficiency anemia
d) Sickle cell anemia
Explanation: Oxidative damage in G6PD deficiency → denatured hemoglobin → Heinz bodies.
Red cell indices are calculated using:
a) PCV, RBC count, Hb ✅
b) WBC count, Hb, MCV
c) Platelet count, Hb, ESR
d) Reticulocyte count, Hb, PCV
Explanation: Indices like MCV, MCH, MCHC are calculated from PCV, Hb, and RBC count.
Mean Corpuscular Volume (MCV) is calculated as:
a) Hb / RBC count ×10
b) PCV / RBC count ×10 ✅
c) Hb / PCV ×100
d) RBC count / Hb ×10
Normal MCHC value:
a) 20–30 g/dL
b) 27–32 g/dL
c) 32–36 g/dL ✅
d) 36–40 g/dL
Microcytic hypochromic anemia is characterized by:
a) ↓MCV, ↓MCHC ✅
b) ↓MCV, ↑MCHC
c) ↑MCV, ↑MCHC
d) ↑MCV, ↓MCHC
Macrocytic anemia is typically caused by:
a) Iron deficiency
b) Vitamin B12 / folate deficiency ✅
c) Hemolysis
d) Chronic blood loss
Schistocytes are indicative of:
a) Megaloblastic anemia
b) Microangiopathic hemolytic anemia ✅
c) Iron deficiency anemia
d) Thalassemia
Basophilic stippling is seen in:
a) Lead poisoning ✅
b) Iron deficiency anemia
c) Megaloblastic anemia
d) Hemophilia
Spherocytes are commonly seen in:
a) Hereditary spherocytosis ✅
b) Thalassemia
c) Sickle cell anemia
d) Aplastic anemia
Bite cells are seen in:
a) Thalassemia
b) G6PD deficiency ✅
c) Megaloblastic anemia
d) Iron deficiency anemia
Target cells appear in:
a) Thalassemia ✅
b) Sickle cell anemia
c) Hereditary spherocytosis
d) Iron deficiency anemia
Rouleaux formation is associated with:
a) Iron deficiency
b) Multiple myeloma ✅
c) Spherocytosis
d) Thalassemia
Reticulocyte count indicates:
a) Platelet function
b) Bone marrow activity ✅
c) RBC shape
d) Hemoglobin content
Reticulocytes are stained by:
a) Leishman stain
b) New Methylene Blue ✅
c) Wright’s stain
d) Giemsa stain
Perls’ Prussian blue stain detects:
a) Lipids
b) Iron ✅
c) RNA
d) DNA
Sudan Black B stains:
a) Glycogen
b) Lipids ✅
c) Proteins
d) Hemoglobin
PAS stain is positive in:
a) ALL ✅
b) AML
c) CML
d) CLL
Early indicator of iron deficiency:
a) Serum ferritin ✅
b) Hemoglobin
c) MCV
d) Serum iron
Serum haptoglobin decreases in:
a) Iron deficiency
b) Hemolytic anemia ✅
c) Megaloblastic anemia
d) Aplastic anemia
Hypersegmented neutrophils are seen in:
a) Iron deficiency
b) Megaloblastic anemia ✅
c) Hemolytic anemia
d) Aplastic anemia
Philadelphia chromosome (t9;22) is associated with:
a) AML
b) CML ✅
c) ALL
d) CLL
Auer rods are seen in:
a) AML ✅
b) ALL
c) CLL
d) CML
Reed–Sternberg cells are seen in:
a) Multiple myeloma
b) Hodgkin lymphoma ✅
c) Non-Hodgkin lymphoma
d) CLL
Smudge cells are typical of:
a) AML
b) CML
c) CLL ✅
d) ALL
Bence–Jones proteins are found in:
a) Hemophilia
b) Multiple myeloma ✅
c) CML
d) Hodgkin lymphoma
Most common leukemia in children:
a) AML
b) ALL ✅
c) CML
d) CLL
Most common acute leukemia in adults:
a) CML
b) AML ✅
c) ALL
d) CLL
CLL is most common in:
a) Children
b) Young adults
c) Elderly ✅
d) Middle-aged
Classical triad of multiple myeloma includes all EXCEPT:
a) Bone pain
b) Anemia
c) Thrombocytosis ✅
d) Bence–Jones proteinuria
RBC MCH formula:
a) Hb ×10 / RBC count ✅
b) Hb ×100 / Hct
c) PCV / RBC count
d) RBC × Hb / Hct
MCHC formula:
a) Hb ×100 / Hct ✅
b) Hb ×10 / RBC
c) Hct ×10 / Hb
d) RBC ×10 / Hb
RDW measures:
a) RBC size variation ✅
b) RBC shape
c) Hemoglobin content
d) Platelet volume
Sodium citrate is used for:
a) CBC
b) Coagulation studies ✅
c) ESR
d) Serum chemistry
Coombs’ test detects:
a) Platelet defects
b) Antibodies on RBCs ✅
c) Hemoglobin deficiency
d) Clotting factors
Direct Coombs is used for:
a) Autoimmune hemolytic anemia ✅
b) Hemophilia
c) Iron deficiency
d) Polycythemia
Indirect Coombs is used for:
a) Cross-matching ✅
b) Hemophilia
c) ESR
d) Reticulocyte count
Bombay blood group lacks:
a) A antigen
b) B antigen
c) H antigen ✅
d) Rh antigen
Universal donor RBC group:
a) AB+
b) O– ✅
c) AB–
d) O+
Universal recipient RBC group:
a) O–
b) AB+ ✅
c) AB–
d) O+
Hemolytic anemia shows which lab findings?
a) ↑Reticulocyte count ✅
b) ↓LDH
c) ↑Haptoglobin
d) ↓Indirect bilirubin
Bone marrow in megaloblastic anemia is typically:
a) Hypocellular
b) Hypercellular ✅
c) Normocellular
d) Fatty📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Biochemistry MCQ for MLT

The basic building block of proteins is:
a) Fatty acids
b) Amino acids ✅
c) Monosaccharides
d) Nucleotides
Explanation: Proteins are polymers made from amino acids joined by peptide bonds. Amino acids contain an amino group (-NH₂), a carboxyl group (-COOH), and a side chain (R group).
Essential amino acids are:
a) Can be synthesized by the body
b) Must be obtained from diet ✅
c) Stored in liver
d) Found only in plants
Explanation: Essential amino acids cannot be synthesized by humans and must be supplied in the diet. Examples: lysine, leucine, valine.
Peptide bond formation involves:
a) Hydrolysis
b) Dehydration reaction ✅
c) Oxidation
d) Phosphorylation
Explanation: Peptide bonds are formed by condensation (removal of water) between the carboxyl group of one amino acid and the amino group of another.
The primary structure of protein is determined by:
a) Hydrogen bonding
b) Amino acid sequence ✅
c) Disulfide bridges
d) Hydrophobic interactions
Explanation: The sequence of amino acids in a polypeptide chain determines its primary structure; secondary, tertiary, and quaternary structures are determined by folding and interactions.
Which of the following is a nonpolar amino acid?
a) Lysine
b) Leucine ✅
c) Aspartic acid
d) Arginine
Explanation: Leucine is hydrophobic, nonpolar. Lysine and arginine are basic, polar; aspartic acid is acidic, polar.
Denaturation of proteins affects:
a) Primary structure
b) Secondary, tertiary, quaternary structures ✅
c) Peptide bonds
d) Amino acid sequence
Explanation: Denaturation disrupts hydrogen bonds, hydrophobic interactions, and disulfide bridges but does not break peptide bonds or change amino acid sequence.
The enzyme that digests proteins in the stomach is:
a) Trypsin
b) Pepsin ✅
c) Amylase
d) Lipase
Explanation: Pepsin, secreted by gastric chief cells, cleaves peptide bonds in proteins to produce peptides. Trypsin acts in the small intestine.
Enzyme activity is influenced by all EXCEPT:
a) Temperature
b) pH
c) Substrate concentration
d) Atomic number ✅
Explanation: Atomic number has no effect on enzyme activity. Enzyme activity depends on temperature, pH, substrate, and cofactor availability.
Km of an enzyme represents:
a) Maximum velocity
b) Substrate concentration at half Vmax ✅
c) Enzyme concentration
d) Product formed
Explanation: Km is the substrate concentration at which the reaction velocity is half of Vmax; lower Km indicates higher affinity.
Competitive inhibition affects:
a) Vmax
b) Km ✅
c) Both Vmax & Km
d) Neither
Explanation: Competitive inhibitors increase apparent Km (reduce substrate affinity) but do not change Vmax.
Non-competitive inhibition affects:
a) Vmax ✅
b) Km
c) Both Vmax & Km
d) Neither
Explanation: Non-competitive inhibitors reduce Vmax by interfering with enzyme function but do not change substrate affinity (Km remains unchanged).
Glycolysis occurs in:
a) Mitochondria
b) Cytoplasm ✅
c) Nucleus
d) Endoplasmic reticulum
Explanation: Glycolysis occurs in the cytoplasm and is anaerobic.
End product of glycolysis under aerobic conditions is:
a) Lactate
b) Pyruvate ✅
c) Acetyl-CoA
d) Glucose
Explanation: Glucose is converted to 2 molecules of pyruvate, which can enter mitochondria for the TCA cycle.
End product of glycolysis under anaerobic conditions is:
a) Pyruvate
b) Lactate ✅
c) Acetyl-CoA
d) Oxaloacetate
Explanation: Pyruvate is converted to lactate to regenerate NAD⁺ under anaerobic conditions.
The rate-limiting enzyme of glycolysis is:
a) Hexokinase
b) Phosphofructokinase-1 ✅
c) Pyruvate kinase
d) Glucose-6-phosphate dehydrogenase
Explanation: Phosphofructokinase-1 regulates glycolysis; it is allosterically inhibited by ATP and citrate, activated by AMP.
Glycogen storage occurs mainly in:
a) Brain
b) Liver & muscle ✅
c) Kidney
d) Spleen
Explanation: Liver glycogen maintains blood glucose; muscle glycogen is used locally for energy.
Hormone responsible for glycogenolysis is:
a) Insulin
b) Glucagon ✅
c) T3
d) Cortisol
Explanation: Glucagon (and epinephrine) stimulates glycogen breakdown in liver to increase blood glucose.
Insulin promotes:
a) Glycogenolysis
b) Glycogenesis ✅
c) Gluconeogenesis
d) Lipolysis
Explanation: Insulin stimulates glycogen synthesis (glycogenesis), promotes glucose uptake, and inhibits gluconeogenesis.
Gluconeogenesis occurs mainly in:
a) Liver & kidney ✅
b) Muscle
c) Adipose tissue
d) Brain
Explanation: Gluconeogenesis is the formation of glucose from non-carbohydrate sources, mainly in liver, to maintain blood glucose.
Cori cycle involves:
a) Lactate conversion to glucose in liver ✅
b) Glucose to pyruvate in muscle
c) Fatty acid synthesis
d) Ketone body formation
Explanation: Muscle lactate is transported to liver and converted back to glucose via gluconeogenesis.
Normal fasting blood glucose level is:
a) 40–70 mg/dL
b) 70–110 mg/dL ✅
c) 120–160 mg/dL
d) 160–200 mg/dL
Explanation: Normal fasting glucose: 70–110 mg/dL; levels >126 mg/dL indicate diabetes.
Hyperglycemia is defined as:
a) <70 mg/dL
b) >126 mg/dL fasting ✅
c) >200 mg/dL postprandial
d) Both b & c ✅
Explanation: Fasting glucose >126 mg/dL or postprandial >200 mg/dL is diagnostic of diabetes.
Glycated hemoglobin (HbA1c) indicates:
a) Blood glucose at a single time
b) Average glucose over 2–3 months ✅
c) Serum insulin
d) C-peptide
Explanation: HbA1c reflects the glycation of hemoglobin, correlating with mean glucose over previous 2–3 months.
Lipids are hydrolyzed by:
a) Lipase ✅
b) Amylase
c) Protease
d) Lactase
Explanation: Lipase hydrolyzes triglycerides into glycerol and free fatty acids.
VLDL carries:
a) Triglycerides ✅
b) Cholesterol
c) Phospholipids
d) Proteins
Explanation: Very-low-density lipoprotein transports triglycerides from liver to peripheral tissues.
LDL is known as:
a) Good cholesterol
b) Bad cholesterol ✅
c) Neutral lipid
d) None
Explanation: LDL carries cholesterol to tissues; high LDL → atherosclerosis risk.
HDL is responsible for:
a) Cholesterol transport to liver ✅
b) Delivering triglycerides
c) Fat storage
d) Ketone body formation
Explanation: HDL removes excess cholesterol from tissues and transports it to liver for excretion.
Cholesterol is synthesized mainly in:
a) Liver ✅
b) Kidney
c) Muscle
d) Brain
Explanation: Liver is the major site of cholesterol biosynthesis; brain synthesizes its own cholesterol independently.
Rate-limiting enzyme of cholesterol synthesis:
a) HMG-CoA reductase ✅
b) Acetyl-CoA carboxylase
c) Lipoprotein lipase
d) Lecithin-cholesterol acyltransferase
Explanation: HMG-CoA reductase converts HMG-CoA → mevalonate; target for statins.
Ketone bodies include all EXCEPT:
a) Acetoacetate
b) β-hydroxybutyrate
c) Acetone
d) Acetyl-CoA ✅
Explanation: Ketone bodies are acetoacetate, β-hydroxybutyrate, acetone; acetyl-CoA is a precursor.
Normal serum urea level:
a) 10–40 mg/dL ✅
b) 5–15 mg/dL
c) 50–80 mg/dL
d) 100–120 mg/dL
Explanation: Urea is a nitrogenous waste from protein catabolism; normal 10–40 mg/dL.
Normal serum creatinine level (male):
a) 0.6–1.2 mg/dL ✅
b) 1.5–2.5 mg/dL
c) 2.5–4 mg/dL
d) 0.2–0.5 mg/dL
Explanation: Creatinine reflects kidney function; stable, unaffected by diet.
Creatinine is a product of:
a) Glucose metabolism
b) Muscle metabolism ✅
c) Fat metabolism
d) Liver metabolism
Explanation: Creatinine is generated from creatine phosphate in muscles, excreted by kidneys.
Jaundice occurs due to:
a) ↑Serum bilirubin ✅
b) ↑Serum albumin
c) ↓Serum urea
d) ↑Serum glucose
Explanation: Hyperbilirubinemia leads to yellow discoloration of skin and sclera.
Direct bilirubin is:
a) Unconjugated
b) Conjugated ✅
c) Free bilirubin
d) Indirect bilirubin
Explanation: Direct (conjugated) bilirubin is water-soluble, conjugated in liver with glucuronic acid.
Indirect bilirubin is:
a) Conjugated
b) Unconjugated ✅
c) Direct bilirubin
d) Water soluble
Explanation: Unconjugated bilirubin is insoluble, bound to albumin, elevated in hemolysis.
Liver function tests include all EXCEPT:
a) ALT
b) AST
c) ALP
d) Serum creatinine ✅
ALP is increased in:
a) Hepatitis
b) Cholestasis ✅
c) Hemolytic anemia
d) Hypoglycemia
Explanation: Alkaline phosphatase (ALP) is elevated in bile duct obstruction, cholestasis, bone diseases.
AST/ALT ratio >2 suggests:
a) Viral hepatitis
b) Alcoholic liver disease ✅
c) Hemochromatosis
d) Wilson’s disease
Explanation: AST > ALT (ratio >2) is characteristic of alcoholic liver disease; in viral hepatitis, ALT > AST.
Amylase is secreted by:
a) Liver
b) Pancreas & salivary glands ✅
c) Kidney
d) Small intestine
Explanation: Amylase hydrolyzes starch to maltose; elevated in pancreatitis and salivary gland disorders.
Lipase is a marker of:
a) Liver disease
b) Pancreatitis ✅
c) Diabetes
d) Kidney disease
Explanation: Lipase is secreted by pancreas; more specific than amylase for pancreatitis.
Troponin is a marker of:
a) Liver injury
b) Myocardial injury ✅
c) Pancreatic injury
d) Hemolysis
Explanation: Cardiac troponins (I, T) are specific for myocardial cell injury; used in diagnosing myocardial infarction.
Serum albumin is:
a) Negative acute phase protein
b) Major plasma protein ✅
c) Enzyme
d) Hormone
Explanation: Albumin is the major plasma protein; maintains oncotic pressure and transports substances.
Serum globulins include:
a) α, β, γ globulins ✅
b) Only α globulins
c) Only γ globulins
d) Only β globulins
Explanation: Globulins are classified into α, β, γ fractions based on electrophoresis; γ-globulins mainly represent immunoglobulins.
A/G ratio less than 1 indicates:
a) Normal
b) Chronic liver disease ✅
c) Hemophilia
d) Dehydration
Explanation: Albumin/globulin (A/G) ratio <1 suggests decreased albumin or increased globulins, common in liver disease, multiple myeloma.
Normal serum sodium level:
a) 120–130 mmol/L
b) 135–145 mmol/L ✅
c) 150–160 mmol/L
d) 100–110 mmol/L
Explanation: Sodium is the main extracellular cation; normal range 135–145 mmol/L.
Normal serum potassium level:
a) 2–3 mmol/L
b) 3.5–5 mmol/L ✅
c) 5–6 mmol/L
d) 6–7 mmol/L
Explanation: Potassium is the main intracellular cation; levels <3.5 → hypokalemia, >5 → hyperkalemia.
Normal serum calcium level:
a) 6–8 mg/dL
b) 8.5–10.5 mg/dL ✅
c) 11–13 mg/dL
d) 12–15 mg/dL
Explanation: Calcium is critical for bone, nerve, muscle function; normal serum: 8.5–10.5 mg/dL.
Total CO₂ in blood mainly reflects:
a) Oxygen
b) Bicarbonate ✅
c) Carbonic acid
d) CO₂ content in RBCs
Explanation: Total CO₂ is mostly bicarbonate (HCO₃⁻) in plasma, reflecting acid-base status.
Normal serum phosphate level:
a) 0.5–1 mg/dL
b) 2.5–4.5 mg/dL ✅
c) 5–6 mg/dL
d) 6–8 mg/dL
Explanation: Phosphate is essential for energy (ATP) and bone mineralization; normal serum 2.5–4.5 mg/dL.
The primary source of energy in the body is:
a) Proteins
b) Fats
c) Carbohydrates ✅
d) Vitamins
Explanation: Carbohydrates are the main energy source; glucose is metabolized to produce ATP.
Glucose transporter in muscles and adipose tissue is:
a) GLUT1
b) GLUT2
c) GLUT4 ✅
d) GLUT3
Explanation: GLUT4 is insulin-dependent and transports glucose into muscle and fat cells.
Glycolysis yields how many ATP per glucose molecule:
a) 2 ✅
b) 4
c) 6
d) 8
Explanation: Net ATP from glycolysis is 2 ATP per glucose (4 produced minus 2 used).
The Cori cycle helps in:
a) Converting glucose to glycogen in liver
b) Recycling lactate to glucose in liver ✅
c) Lipid metabolism
d) Amino acid metabolism
Explanation: Muscle lactate is transported to liver and converted back to glucose, preventing lactic acidosis.
Pyruvate dehydrogenase converts pyruvate into:
a) Lactate
b) Acetyl-CoA ✅
c) Oxaloacetate
d) Alanine
Explanation: Pyruvate enters the mitochondria and is converted into acetyl-CoA, entering the TCA cycle.
Rate-limiting enzyme of the TCA cycle:
a) Citrate synthase
b) Isocitrate dehydrogenase ✅
c) Malate dehydrogenase
d) α-Ketoglutarate dehydrogenase
Explanation: Isocitrate dehydrogenase regulates the TCA cycle; inhibited by ATP and NADH.
Electron transport chain occurs in:
a) Cytoplasm
b) Mitochondrial matrix
c) Inner mitochondrial membrane ✅
d) Nucleus
Explanation: ETC complexes I–IV are embedded in the inner mitochondrial membrane; ATP synthase generates ATP.
Oxidative phosphorylation produces approximately how many ATP per glucose:
a) 12
b) 24
c) 34–36 ✅
d) 40–42
Explanation: ETC and oxidative phosphorylation yield ~34 ATP per glucose in eukaryotes.
Fatty acid synthesis occurs in:
a) Cytoplasm ✅
b) Mitochondria
c) ER
d) Golgi apparatus
Explanation: Acetyl-CoA is transported to cytoplasm, converted to malonyl-CoA, then elongated to fatty acids.
Rate-limiting enzyme of fatty acid synthesis:
a) HMG-CoA reductase
b) Acetyl-CoA carboxylase ✅
c) Lipoprotein lipase
d) Fatty acid synthase
Explanation: Acetyl-CoA → malonyl-CoA by acetyl-CoA carboxylase; regulated by citrate (activator) and palmitoyl-CoA (inhibitor).
Ketone bodies are formed during:
a) High carbohydrate diet
b) Fasting/starvation ✅
c) Normal fed state
d) Protein deficiency only
Explanation: Ketogenesis occurs in liver mitochondria during prolonged fasting or uncontrolled diabetes.
Rate-limiting enzyme of ketone body formation:
a) HMG-CoA synthase ✅
b) HMG-CoA reductase
c) Lipoprotein lipase
d) Pyruvate carboxylase
Explanation: HMG-CoA synthase catalyzes formation of HMG-CoA, precursor of ketone bodies.
Main site of cholesterol synthesis:
a) Kidney
b) Liver ✅
c) Brain
d) Intestine
Explanation: Liver synthesizes cholesterol using acetyl-CoA; regulated by HMG-CoA reductase.
Statins inhibit:
a) HMG-CoA synthase
b) HMG-CoA reductase ✅
c) Acetyl-CoA carboxylase
d) Lipoprotein lipase
Explanation: Statins block cholesterol synthesis, lowering LDL cholesterol levels.
Lipoproteins transporting triglycerides from liver to tissues:
a) LDL
b) VLDL ✅
c) HDL
d) Chylomicrons
Explanation: VLDL carries triglycerides synthesized in liver to peripheral tissues.
HDL function:
a) Deliver triglycerides
b) Reverse cholesterol transport ✅
c) Energy storage
d) Ketone body formation
Explanation: HDL removes cholesterol from peripheral tissues and transports it to liver for excretion.
Glycogen branching enzyme deficiency causes:
a) McArdle disease
b) Pompe disease ✅
c) Von Gierke disease
d) Tay-Sachs disease
Explanation: Deficiency in α-1,6-glucosidic branching enzyme causes Pompe disease (glycogen storage in lysosomes).
Von Gierke disease is due to:
a) Glucose-6-phosphatase deficiency ✅
b) Glycogen synthase deficiency
c) Phosphofructokinase deficiency
d) Lactase deficiency
Explanation: Glucose-6-phosphatase deficiency leads to impaired gluconeogenesis and glycogenolysis.
Enzyme responsible for breaking down dietary starch:
a) Amylase ✅
b) Lipase
c) Protease
d) Maltase
Explanation: Salivary and pancreatic amylase hydrolyze starch to maltose and dextrins.
Lactose intolerance occurs due to:
a) Lack of amylase
b) Lack of lipase
c) Lack of lactase ✅
d) Lack of maltase
Explanation: Lactase deficiency prevents hydrolysis of lactose to glucose and galactose, causing diarrhea.
Normal fasting blood glucose:
a) 60–80 mg/dL
b) 70–110 mg/dL ✅
c) 120–140 mg/dL
d) 140–180 mg/dL
Explanation: Normal fasting glucose is 70–110 mg/dL; above 126 mg/dL indicates diabetes.
HbA1c reflects:
a) Immediate blood glucose
b) Average glucose 2–3 months ✅
c) Serum insulin
d) C-peptide
Explanation: HbA1c indicates long-term glycemic control; formed by non-enzymatic glycation of hemoglobin.
Enzyme for triglyceride hydrolysis in blood:
a) Hormone-sensitive lipase
b) Lipoprotein lipase ✅
c) Pancreatic lipase
d) Amylase
Explanation: Lipoprotein lipase hydrolyzes circulating triglycerides in chylomicrons and VLDL.
Hyperlipidemia can cause:
a) Atherosclerosis ✅
b) Hypoglycemia
c) Anemia
d) Renal failure
Explanation: High LDL and triglycerides contribute to plaque formation and cardiovascular disease.
Urea cycle occurs in:
a) Cytoplasm only
b) Mitochondria only
c) Liver (mitochondria + cytoplasm) ✅
d) Kidney
Explanation: Urea cycle detoxifies ammonia; occurs in liver, partly in mitochondria and partly in cytoplasm.
Enzyme converting ammonia to carbamoyl phosphate:
a) Ornithine transcarbamylase
b) Carbamoyl phosphate synthetase I ✅
c) Arginase
d) Glutamate dehydrogenase
Explanation: Carbamoyl phosphate synthetase I catalyzes first step of urea cycle; N-acetylglutamate is activator.
Hyperammonemia leads to:
a) Liver failure ✅
b) Diabetes
c) Hypoglycemia
d) Hyperlipidemia
Explanation: Accumulation of ammonia is toxic to CNS, causing encephalopathy.
Normal serum urea:
a) 5–15 mg/dL
b) 10–40 mg/dL ✅
c) 50–80 mg/dL
d) 100–120 mg/dL
Normal serum creatinine (male):
a) 0.6–1.2 mg/dL ✅
b) 1.5–2.5 mg/dL
c) 2.5–4 mg/dL
d) 0.2–0.5 mg/dL
Liver function test includes all EXCEPT:
a) ALT
b) AST
c) ALP
d) Serum creatinine ✅
ALT is more specific for:
a) Liver ✅
b) Kidney
c) Pancreas
d) Heart
AST is found in:
a) Liver
b) Heart
c) Muscle
d) All above ✅
Cholestasis increases:
a) ALT
b) AST
c) ALP ✅
d) Amylase
Total bilirubin =
a) Direct + Indirect ✅
b) Direct only
c) Indirect only
d) Conjugated only
Conjugated bilirubin is:
a) Indirect
b) Direct ✅
c) Free
d) Albumin-bound
Unconjugated bilirubin is:
a) Direct
b) Indirect ✅
c) Water-soluble
d) None
Hyperbilirubinemia causes:
a) Jaundice ✅
b) Hypoglycemia
c) Hyperlipidemia
d) None
Pancreatic amylase is more specific than salivary amylase for:
a) Liver disease
b) Pancreatitis ✅
c) Diabetes
d) Kidney disease
Lipase is mainly elevated in:
a) Pancreatitis ✅
b) Liver disease
c) Kidney disease
d) Muscle injury
Troponin I/T is a marker of:
a) Liver injury
b) Cardiac injury ✅
c) Pancreatic injury
d) Hemolysis
Serum albumin maintains:
a) Acid-base balance
b) Oncotic pressure ✅
c) Blood glucose
d) Electrolyte balance
Globulins include:
a) α, β, γ ✅
b) Only α
c) Only γ
d) Only β
Low A/G ratio indicates:
a) Liver disease ✅
b) Dehydration
c) Hemorrhage
d) None
Sodium normal range:
a) 135–145 mmol/L ✅
b) 120–130 mmol/L
c) 150–160 mmol/L
d) 100–110 mmol/L
Potassium normal range:
a) 2–3 mmol/L
b) 3.5–5 mmol/L ✅
c) 5–6 mmol/L
d) 6–7 mmol/L
Calcium normal range:
a) 8.5–10.5 mg/dL ✅
b) 6–8 mg/dL
c) 11–13 mg/dL
d) 12–15 mg/dL
Phosphate normal range:
a) 2.5–4.5 mg/dL ✅
b) 0.5–1 mg/dL
c) 5–6 mg/dL
d) 6–8 mg/dL
Total CO₂ mainly reflects:
a) Oxygen
b) Bicarbonate ✅
c) Carbonic acid
d) CO₂ in RBCs
Hypernatremia indicates:
a) Water loss ✅
b) Sodium loss
c) Hypovolemia
d) Hyperkalemia
Hypokalemia can cause:
a) Muscle weakness ✅
b) Hyperactivity
c) Bradycardia
d) Hypertension📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test
Serum urea is mainly formed from:
a) Carbohydrate metabolism
b) Fat metabolism
c) Protein metabolism ✅
d) Nucleic acid metabolism
Explanation: Urea is produced in the liver during the breakdown of amino acids. Nitrogen from amino groups is converted to urea and excreted by the kidneys.
Normal serum urea level:
a) 5–15 mg/dL
b) 10–40 mg/dL ✅
c) 50–80 mg/dL
d) 100–120 mg/dL
Explanation: The normal range reflects adequate renal function and protein metabolism; values above this suggest renal impairment or high protein intake.
Serum creatinine is a marker of:
a) Liver function
b) Renal function ✅
c) Pancreatic function
d) Cardiac function
Explanation: Creatinine is produced from creatine in muscles and is excreted by kidneys; elevated serum creatinine indicates reduced kidney filtration (GFR).
Normal serum creatinine (male):
a) 0.6–1.2 mg/dL ✅
b) 1.5–2.5 mg/dL
c) 2.5–4 mg/dL
d) 0.2–0.5 mg/dL
Explanation: Normal male creatinine varies due to muscle mass; values above 1.2 mg/dL suggest possible kidney dysfunction.
Creatinine clearance is used to estimate:
a) Liver function
b) Glomerular filtration rate (GFR) ✅
c) Pancreatic function
d) Cardiac output
Explanation: Measurement of creatinine clearance from blood and urine assesses kidney’s ability to filter creatinine, providing an estimate of GFR.
Blood urea nitrogen (BUN) is:
a) Urea in blood ✅
b) Creatinine in blood
c) Ammonia in blood
d) Electrolytes in blood
Explanation: BUN represents the nitrogen portion of urea in plasma; it helps assess renal function and protein metabolism.
Hyperuremia indicates:
a) Liver failure
b) Kidney dysfunction ✅
c) Hypoglycemia
d) Hyperlipidemia
Explanation: Elevated serum urea may result from decreased renal clearance, high protein intake, or increased protein catabolism.
Hypouricemia can occur in:
a) Gout
b) Wilson’s disease ✅
c) Kidney failure
d) Hyperthyroidism
Explanation: Low serum uric acid is seen in Wilson’s disease, certain medications, or renal tubular defects.
Normal serum uric acid (male):
a) 2–4 mg/dL
b) 3.5–7.2 mg/dL ✅
c) 7–10 mg/dL
d) 1–3 mg/dL
Explanation: Normal male range is 3.5–7.2 mg/dL; values above this can lead to gout, kidney stones.
Hyperuricemia can lead to:
a) Hypoglycemia
b) Gout ✅
c) Hypertension
d) Anemia
Explanation: Excess uric acid precipitates as monosodium urate crystals in joints causing inflammation (gout).
ALT (SGPT) is mainly found in:
a) Liver ✅
b) Kidney
c) Pancreas
d) Heart
Explanation: ALT is a liver-specific enzyme; elevated levels indicate hepatocellular injury.
AST (SGOT) is found in:
a) Liver, heart, muscle ✅
b) Liver only
c) Heart only
d) Pancreas only
Explanation: AST is present in multiple tissues; elevated levels can indicate liver injury, myocardial infarction, or muscle damage.
ALT is more specific for:
a) Liver ✅
b) Heart
c) Kidney
d) Pancreas
Explanation: ALT has high specificity for hepatocellular injury compared to AST.
AST/ALT ratio >2 indicates:
a) Viral hepatitis
b) Alcoholic liver disease ✅
c) Hemolysis
d) Renal disease
Explanation: High AST relative to ALT is characteristic of alcoholic liver disease; viral hepatitis usually has ALT > AST.
ALP (Alkaline phosphatase) is increased in:
a) Liver disease
b) Bone disease
c) Cholestasis ✅
d) Diabetes
Explanation: ALP rises in bile duct obstruction, cholestasis, and bone disorders.
Bilirubin is conjugated in:
a) Kidney
b) Liver ✅
c) Muscle
d) Spleen
Explanation: In hepatocytes, bilirubin is conjugated with glucuronic acid making it water-soluble for excretion in bile.
Direct bilirubin is:
a) Unconjugated
b) Conjugated ✅
c) Free
d) Bound to albumin
Explanation: Direct (conjugated) bilirubin is water-soluble and can be excreted into bile.
Indirect bilirubin is:
a) Conjugated
b) Unconjugated ✅
c) Direct
d) Water-soluble
Explanation: Indirect (unconjugated) bilirubin is lipid-soluble, bound to albumin in plasma, and transported to the liver.
Jaundice occurs when:
a) Bilirubin <1 mg/dL
b) Bilirubin >2–2.5 mg/dL ✅
c) Bilirubin = 1 mg/dL
d) Bilirubin <0.5 mg/dL
Explanation: Clinical jaundice appears when total serum bilirubin exceeds ~2–2.5 mg/dL.
Causes of pre-hepatic jaundice include:
a) Hemolysis ✅
b) Hepatitis
c) Cholestasis
d) Cirrhosis
Explanation: Increased bilirubin production from hemolysis overwhelms liver’s conjugation capacity.
Causes of hepatic jaundice include:
a) Hemolysis
b) Hepatitis ✅
c) Bile duct obstruction
d) Pancreatitis
Explanation: Hepatocellular injury impairs bilirubin conjugation and excretion.
Causes of post-hepatic jaundice include:
a) Hemolysis
b) Bile duct obstruction ✅
c) Hepatitis
d) Wilson’s disease
Explanation: Obstruction of bile flow (gallstones, tumors) leads to conjugated hyperbilirubinemia.
Amylase is elevated in:
a) Pancreatitis ✅
b) Liver disease
c) Renal disease
d) Cardiac disease
Explanation: Serum amylase rises within hours of pancreatic injury.
Lipase is more specific than amylase for:
a) Liver disease
b) Pancreatitis ✅
c) Kidney disease
d) Muscle injury
Explanation: Lipase is produced only by pancreas and remains elevated longer than amylase.
Cardiac troponins I and T are markers of:
a) Liver injury
b) Myocardial injury ✅
c) Renal failure
d) Pancreatitis
Explanation: Troponins are highly specific proteins released from damaged heart muscle.
CK-MB is a marker of:
a) Liver injury
b) Myocardial injury ✅
c) Pancreatic injury
d) Kidney injury
Explanation: Creatine kinase MB isoenzyme is elevated in myocardial infarction.
Serum electrolytes include all EXCEPT:
a) Sodium
b) Potassium
c) Calcium
d) Glucose ✅
Explanation: Electrolytes are ions like Na⁺, K⁺, Ca²⁺, Cl⁻, and phosphate; glucose is not an electrolyte.
Normal serum sodium:
a) 135–145 mmol/L ✅
b) 120–130 mmol/L
c) 150–160 mmol/L
d) 100–110 mmol/L
Explanation: Sodium is the major extracellular cation; abnormal levels cause fluid and electrolyte imbalance.
Hypernatremia indicates:
a) Water loss ✅
b) Sodium loss
c) Hypovolemia
d) Hyperkalemia
Explanation: Elevated serum sodium occurs with dehydration, hypertonic saline, or diabetes insipidus.
Hyponatremia causes:
a) Water retention ✅
b) Diabetes
c) Hyperthyroidism
d) Hyperkalemia
Explanation: Low sodium may occur due to excessive water retention, SIADH, or diuretic use.
Normal serum potassium:
a) 2–3 mmol/L
b) 3.5–5 mmol/L ✅
c) 5–6 mmol/L
d) 6–7 mmol/L
Explanation: Potassium is the main intracellular cation; levels outside range can cause cardiac arrhythmias.
Hypokalemia may cause:
a) Muscle weakness ✅
b) Hyperactivity
c) Bradycardia
d) Hypertension
Hyperkalemia may cause:
a) Arrhythmia ✅
b) Hypotension
c) Hypoglycemia
d) Muscle spasm
Normal serum calcium:
a) 8.5–10.5 mg/dL ✅
b) 6–8 mg/dL
c) 11–13 mg/dL
d) 12–15 mg/dL
Hypercalcemia causes:
a) Hyperparathyroidism ✅
b) Hypothyroidism
c) Addison’s disease
d) Diabetes
Hypocalcemia may occur in:
a) Vitamin D deficiency ✅
b) Hyperthyroidism
c) Hyperparathyroidism
d) Gout
Normal serum phosphate:
a) 2.5–4.5 mg/dL ✅
b) 0.5–1 mg/dL
c) 5–6 mg/dL
d) 6–8 mg/dL
Hyperphosphatemia causes:
a) Renal failure ✅
b) Hyperparathyroidism
c) Vitamin D deficiency
d) Gout
Hypophosphatemia causes:
a) Malnutrition ✅
b) Kidney failure
c) Hyperparathyroidism
d) Addison’s disease
Total CO₂ mainly represents:
a) Oxygen
b) Bicarbonate ✅
c) Carbonic acid
d) CO₂ in RBCs
Explanation: Total CO₂ measures bicarbonate, reflecting acid-base balance.
Anion gap is calculated as:
a) Na⁺ + K⁺ – Cl⁻ – HCO₃⁻ ✅
b) Na⁺ – K⁺
c) Cl⁻ – HCO₃⁻
d) Na⁺ + Cl⁻
Elevated anion gap indicates:
a) Metabolic acidosis ✅
b) Metabolic alkalosis
c) Respiratory acidosis
d) Respiratory alkalosis
Normal fasting blood glucose:
a) 60–80 mg/dL
b) 70–110 mg/dL ✅
c) 120–140 mg/dL
d) 140–180 mg/dL
Postprandial blood glucose normal:
a) <140 mg/dL ✅
b) <120 mg/dL
c) <160 mg/dL
d) <180 mg/dL
HbA1c normal range:
a) 4–5%
b) 4–6% ✅
c) 6–8%
d) 7–9%
Explanation: HbA1c reflects average blood glucose over 2–3 months. Normal range: 4–6%. Values >6.5% indicate diabetes.
Lipid profile includes:
a) Total cholesterol, HDL, LDL, triglycerides ✅
b) Urea, creatinine
c) Bilirubin, ALT
d) Sodium, potassium
Explanation: Lipid profile assesses cardiovascular risk; HDL is protective, LDL is atherogenic.
Hypercholesterolemia can cause:
a) Atherosclerosis ✅
b) Hypoglycemia
c) Anemia
d) Hypernatremia
Explanation: High LDL cholesterol promotes plaque formation in arteries, increasing cardiovascular disease risk.
Triglycerides are transported mainly by:
a) HDL
b) LDL
c) VLDL ✅
d) Chylomicrons
Explanation: VLDL transports endogenous triglycerides from liver to peripheral tissues; chylomicrons transport dietary triglycerides.
Pancreatic function tests include:
a) Amylase, Lipase ✅
b) ALT, AST
c) Urea, Creatinine
d) Sodium, Potassium
Explanation: Serum amylase and lipase are measured to diagnose pancreatitis; lipase is more specific for pancreatic injury.
The main site of gluconeogenesis is:
a) Muscle
b) Liver ✅
c) Kidney
d) Brain
Explanation: Gluconeogenesis primarily occurs in the liver, converting non-carbohydrate substrates (lactate, glycerol, amino acids) to glucose during fasting.
Gluconeogenesis is inhibited by:
a) Glucagon
b) Insulin ✅
c) Cortisol
d) Epinephrine
Explanation: Insulin promotes glucose utilization and inhibits gluconeogenesis, lowering blood glucose levels.
Rate-limiting enzyme of gluconeogenesis:
a) Pyruvate kinase
b) Phosphofructokinase
c) Fructose-1,6-bisphosphatase ✅
d) Glucose-6-phosphatase
Explanation: Fructose-1,6-bisphosphatase converts F-1,6-BP to F-6-P, regulating gluconeogenesis.
Glycogen synthase is activated by:
a) Glucagon
b) Insulin ✅
c) Epinephrine
d) Cortisol
Explanation: Insulin promotes glycogen synthesis by activating glycogen synthase, facilitating glucose storage.
Glycogen phosphorylase is activated by:
a) Insulin
b) Glucagon ✅
c) ATP
d) G6P
Explanation: Glucagon and epinephrine activate glycogen phosphorylase via cAMP, promoting glycogen breakdown.
Pentose phosphate pathway produces:
a) ATP
b) NADPH and ribose-5-phosphate ✅
c) FADH₂
d) Acetyl-CoA
Explanation: PPP generates NADPH for biosynthesis and ribose-5-phosphate for nucleotide synthesis.
Rate-limiting enzyme of PPP:
a) Glucose-6-phosphate dehydrogenase ✅
b) Phosphofructokinase
c) Hexokinase
d) Pyruvate kinase
Explanation: G6PD catalyzes the first step in PPP; deficiency leads to hemolytic anemia.
Fatty acid β-oxidation occurs in:
a) Cytoplasm
b) Mitochondrial matrix ✅
c) ER
d) Nucleus
Explanation: Fatty acids are broken down in mitochondria into acetyl-CoA for energy production.
Ketone bodies include:
a) Acetoacetate, β-hydroxybutyrate, acetone ✅
b) Glucose, lactate
c) Pyruvate, citrate
d) Acetyl-CoA only
Explanation: Ketone bodies are produced in liver during fasting or diabetes; serve as alternative energy source.
HMG-CoA reductase inhibitors are:
a) Statins ✅
b) Fibrates
c) Niacin
d) Bile acid sequestrants
Explanation: Statins inhibit HMG-CoA reductase, reducing cholesterol synthesis.
Lipoproteins carrying dietary triglycerides:
a) LDL
b) HDL
c) Chylomicrons ✅
d) VLDL
Explanation: Chylomicrons transport dietary lipids from intestines to peripheral tissues.
Lipoproteins responsible for reverse cholesterol transport:
a) LDL
b) HDL ✅
c) VLDL
d) Chylomicrons
Explanation: HDL removes cholesterol from tissues to liver for excretion.
Enzyme converting pyruvate to lactate:
a) Pyruvate dehydrogenase
b) Lactate dehydrogenase ✅
c) Hexokinase
d) Glucose-6-phosphate dehydrogenase
Explanation: Lactate dehydrogenase reduces pyruvate to lactate during anaerobic glycolysis.
Enzyme converting pyruvate to acetyl-CoA:
a) Lactate dehydrogenase
b) Pyruvate dehydrogenase ✅
c) Pyruvate kinase
d) Hexokinase
Explanation: Pyruvate dehydrogenase links glycolysis to TCA cycle; requires thiamine, lipoic acid, CoA, FAD, NAD⁺.
Rate-limiting enzyme of TCA cycle:
a) Citrate synthase
b) Isocitrate dehydrogenase ✅
c) α-Ketoglutarate dehydrogenase
d) Malate dehydrogenase
Amino acid metabolism produces:
a) Urea ✅
b) Glucose
c) Fatty acids
d) Ketone bodies
Explanation: Deamination of amino acids produces ammonia, converted to urea in liver.
Phenylketonuria is due to deficiency of:
a) Tyrosinase
b) Phenylalanine hydroxylase ✅
c) Homogentisate oxidase
d) Branched-chain α-ketoacid dehydrogenase
Explanation: PKU leads to accumulation of phenylalanine, causing intellectual disability if untreated.
Maple syrup urine disease is due to deficiency of:
a) Phenylalanine hydroxylase
b) Branched-chain α-ketoacid dehydrogenase ✅
c) Tyrosinase
d) Homogentisate oxidase
Explanation: Leads to accumulation of leucine, isoleucine, valine; urine smells like maple syrup.
Alkaptonuria is due to deficiency of:
a) Homogentisate oxidase ✅
b) Phenylalanine hydroxylase
c) Tyrosinase
d) Branched-chain α-ketoacid dehydrogenase
Explanation: Accumulated homogentisic acid causes dark urine and ochronosis.
Vitamin B1 deficiency causes:
a) Beriberi ✅
b) Pellagra
c) Scurvy
d) Rickets
Explanation: Thiamine (B1) deficiency affects energy metabolism → neurological and cardiac manifestations.
Vitamin B2 deficiency causes:
a) Cheilitis, glossitis ✅
b) Night blindness
c) Rickets
d) Bleeding disorders
Explanation: Riboflavin deficiency affects FAD/FMN-dependent reactions.
Vitamin B3 deficiency causes:
a) Scurvy
b) Pellagra ✅
c) Beriberi
d) Rickets
Explanation: Niacin deficiency leads to dermatitis, diarrhea, dementia.
Vitamin B6 deficiency causes:
a) Sideroblastic anemia ✅
b) Megaloblastic anemia
c) Hemolytic anemia
d) Iron-deficiency anemia
Explanation: Pyridoxal phosphate is coenzyme for transamination; deficiency leads to microcytic anemia.
Vitamin B12 deficiency causes:
a) Microcytic anemia
b) Megaloblastic anemia ✅
c) Hemolytic anemia
d) Aplastic anemia
Explanation: B12 deficiency impairs DNA synthesis → megaloblastic anemia.
Folate deficiency causes:
a) Macrocytic anemia ✅
b) Microcytic anemia
c) Hemolytic anemia
d) Sideroblastic anemia
Vitamin C deficiency causes:
a) Scurvy ✅
b) Beriberi
c) Pellagra
d) Rickets
Explanation: Vitamin C is essential for collagen synthesis; deficiency → bleeding gums, bruising.
Vitamin D deficiency causes:
a) Rickets, osteomalacia ✅
b) Scurvy
c) Pellagra
d) Beriberi
Explanation: Vitamin D regulates calcium-phosphate metabolism; deficiency leads to soft bones.
Serum albumin normal range:
a) 3.5–5 g/dL ✅
b) 2–3 g/dL
c) 5–6 g/dL
d) 1–2 g/dL
Hypoalbuminemia indicates:
a) Liver disease ✅
b) Renal failure
c) Dehydration
d) Diabetes
Explanation: Albumin synthesized in liver; low levels suggest liver disease, malnutrition, nephrotic syndrome.
Normal serum total protein:
a) 6–8 g/dL ✅
b) 4–6 g/dL
c) 8–10 g/dL
d) 5–7 g/dL
A/G ratio normally:
a) 0.5–1 ✅
b) 1–2
c) 2–3
d) 0–0.5
Explanation: Albumin/globulin ratio indicates balance of proteins; low ratio occurs in liver disease or multiple myeloma.
Elevated AST and ALT indicate:
a) Pancreatitis
b) Hepatocellular injury ✅
c) Renal failure
d) Diabetes
Elevated ALP and GGT indicate:
a) Hepatocellular injury
b) Cholestasis ✅
c) Renal injury
d) Pancreatitis
Normal fasting glucose:
a) 60–80 mg/dL
b) 70–110 mg/dL ✅
c) 120–140 mg/dL
d) 140–180 mg/dL
Random glucose level in diabetes:
a) ≥140 mg/dL
b) ≥200 mg/dL ✅
c) ≥180 mg/dL
d) ≥120 mg/dL
Oral glucose tolerance test (OGTT) normal 2-hour value:
a) <140 mg/dL ✅
b) 140–199 mg/dL
c) ≥200 mg/dL
d) ≥180 mg/dL
HbA1c reflects:
a) Immediate glucose
b) Average glucose 2–3 months ✅
c) Fasting glucose only
d) Postprandial glucose only
Hyperlipidemia is defined as:
a) High LDL, triglycerides ✅
b) Low HDL
c) Low LDL
d) Low triglycerides
LDL normal range:
a) <100 mg/dL ✅
b) <130 mg/dL
c) <150 mg/dL
d) <200 mg/dL
HDL normal range:
a) >40 mg/dL ✅
b) <40 mg/dL
c) 30–50 mg/dL
d) >60 mg/dL
Triglycerides normal:
a) <150 mg/dL ✅
b) <200 mg/dL
c) <100 mg/dL
d) <50 mg/dL
Cholesterol normal:
a) <200 mg/dL ✅
b) <180 mg/dL
c) <220 mg/dL
d) <240 mg/dL
Enzyme for triglyceride hydrolysis in blood:
a) Lipoprotein lipase ✅
b) Hormone-sensitive lipase
c) Pancreatic lipase
d) Amylase
ALT is measured to assess:
a) Kidney function
b) Liver function ✅
c) Pancreatic function
d) Cardiac function
AST elevation occurs in:
a) Liver, cardiac, muscle injury ✅
b) Liver only
c) Pancreas only
d) Kidney only
Bilirubin is excreted in:
a) Urine
b) Bile ✅
c) Sweat
d) Saliva
Elevated unconjugated bilirubin causes:
a) Hemolytic jaundice ✅
b) Obstructive jaundice
c) Hepatocellular jaundice
d) Pancreatic jaundice
Elevated conjugated bilirubin causes:
a) Obstructive jaundice ✅
b) Hemolytic jaundice
c) Hepatocellular jaundice
d) Renal failure
Pancreatic amylase is elevated in:
a) Pancreatitis ✅
b) Liver disease
c) Kidney disease
d) Heart disease
Pancreatic lipase is preferred marker for:
a) Liver disease
b) Pancreatitis ✅
c) Kidney disease
d) Muscle injury
Serum urea is elevated in:
a) Dehydration ✅
b) Hyperthyroidism
c) Hypoglycemia
d) Anemia

Explanation: Urea is produced in the liver from ammonia during protein metabolism and excreted by kidneys. Serum urea rises in dehydration due to reduced plasma volume, in renal failure due to impaired clearance, or in high-protein diets.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Serum creatinine elevation indicates:
a) Liver disease
b) Renal impairment ✅
c) Hypoglycemia
d) Hyperlipidemia

Explanation: Creatinine is a breakdown product of creatine phosphate in muscles, excreted almost entirely by kidneys. Increased serum creatinine reflects reduced glomerular filtration rate (GFR), indicating kidney dysfunction.

BUN/Creatinine ratio >20:1 indicates:
a) Pre-renal azotemia ✅
b) Post-renal azotemia
c) Intrinsic renal disease
d) Liver failure

Explanation: High BUN relative to creatinine (>20:1) is usually pre-renal, caused by dehydration, decreased renal perfusion, or heart failure. Intrinsic renal disease typically has lower ratio.

Serum uric acid is mainly excreted by:
a) Liver
b) Kidney ✅
c) Pancreas
d) Intestine

Explanation: Uric acid is the end product of purine metabolism. Kidneys excrete ~70%; impaired renal function leads to hyperuricemia and risk of gout or kidney stones.

Hyperuricemia may lead to:
a) Kidney stones, gout ✅
b) Hypoglycemia
c) Liver cirrhosis
d) Hemolytic anemia

Explanation: Elevated uric acid crystallizes in joints (gout) or urinary tract (stones).

Normal fasting blood glucose:
a) 70–110 mg/dL ✅
b) 60–100 mg/dL
c) 80–120 mg/dL
d) 90–130 mg/dL

Explanation: Fasting glucose reflects baseline blood sugar. Levels above 126 mg/dL on two occasions indicate diabetes.

Random glucose level diagnostic of diabetes:
a) ≥140 mg/dL
b) ≥180 mg/dL
c) ≥200 mg/dL ✅
d) ≥160 mg/dL

Explanation: Random plasma glucose ≥200 mg/dL in presence of symptoms (polyuria, polydipsia) is diagnostic.

OGTT 2-hour glucose ≥200 mg/dL indicates:
a) Normal
b) Prediabetes
c) Diabetes ✅
d) Hypoglycemia

Explanation: Oral glucose tolerance test evaluates glucose clearance; ≥200 mg/dL after 2 hours confirms diabetes.

HbA1c reflects:
a) Immediate glucose
b) Average glucose 2–3 months ✅
c) Only fasting glucose
d) Only postprandial glucose

Explanation: Hemoglobin A1c measures glycated hemoglobin, indicating mean blood glucose over 2–3 months, useful for monitoring diabetes control.

Normal HbA1c:
a) 3–4%
b) 4–6% ✅
c) 6–7%
d) 7–8%

Explanation: 4–6% is normal; >6.5% indicates diabetes; 5.7–6.4% is prediabetic range.

Serum total cholesterol normal range:
a) <200 mg/dL ✅
b) <180 mg/dL
c) 200–220 mg/dL
d) <250 mg/dL

Explanation: Total cholesterol <200 mg/dL is desirable; higher levels increase atherosclerosis risk.

LDL cholesterol is considered high at:
a) >100 mg/dL
b) >130 mg/dL ✅
c) >160 mg/dL
d) >200 mg/dL

Explanation: LDL (“bad cholesterol”) >130 mg/dL increases cardiovascular risk.

HDL cholesterol normal (male):
a) >40 mg/dL ✅
b) >50 mg/dL
c) 30–40 mg/dL
d) 20–30 mg/dL

Explanation: HDL (“good cholesterol”) >40 mg/dL for men and >50 mg/dL for women is protective.

Triglycerides normal:
a) <150 mg/dL ✅
b) <200 mg/dL
c) <180 mg/dL
d) <100 mg/dL

Explanation: Elevated triglycerides increase risk of atherosclerosis and pancreatitis.

Liver function tests include:
a) ALT, AST, ALP, bilirubin ✅
b) Urea, creatinine
c) Sodium, potassium
d) Glucose only

Explanation: LFTs assess hepatocellular integrity (ALT, AST) and cholestasis (ALP, bilirubin).

ALT is more specific for:
a) Kidney injury
b) Liver injury ✅
c) Heart injury
d) Muscle injury

Explanation: ALT is predominantly in liver; elevation indicates hepatocellular injury.

AST is found in:
a) Liver, heart, skeletal muscle ✅
b) Liver only
c) Heart only
d) Pancreas only

Explanation: AST elevation occurs in liver disease, MI, or muscle injury, so less liver-specific than ALT.

ALP is elevated in:
a) Hepatocellular injury
b) Cholestasis, bone disease ✅
c) Kidney disease
d) Pancreatitis

Explanation: ALP rises in bile duct obstruction and bone disorders.

GGT is used to differentiate:
a) Hepatocellular vs cholestatic disease ✅
b) Renal vs liver disease
c) Pancreatic vs liver disease
d) Cardiac vs liver disease

Explanation: GGT rises in cholestasis and alcohol-induced liver disease; helps distinguish liver vs bone ALP elevation.

Bilirubin normal range (total):
a) 0.1–1.2 mg/dL ✅
b) 1.5–2.5 mg/dL
c) 2–3 mg/dL
d) 3–4 mg/dL

Explanation: Normal total bilirubin is 0.1–1.2 mg/dL; higher levels cause jaundice.

Unconjugated hyperbilirubinemia indicates:
a) Hemolysis ✅
b) Bile duct obstruction
c) Hepatitis
d) Pancreatitis

Explanation: Unconjugated (indirect) bilirubin rises in hemolysis or impaired hepatic uptake.

Conjugated hyperbilirubinemia indicates:
a) Obstructive jaundice ✅
b) Hemolysis
c) Pre-hepatic jaundice
d) Renal disease

Explanation: Conjugated (direct) bilirubin rises in cholestasis or bile duct obstruction.

Serum amylase is elevated in:
a) Pancreatitis ✅
b) Liver disease
c) Kidney disease
d) Cardiac disease

Explanation: Amylase rises in acute pancreatitis and salivary gland disorders.

Serum lipase is preferred over amylase because:
a) Less specific
b) More specific for pancreas ✅
c) Cheaper
d) Shorter half-life

Explanation: Lipase originates almost exclusively from pancreas and remains elevated longer, making it more specific.

Normal serum sodium:
a) 135–145 mmol/L ✅
b) 120–130 mmol/L
c) 150–160 mmol/L
d) 100–110 mmol/L

Explanation: Sodium maintains osmotic balance; deviation causes neurological symptoms.

Hypernatremia indicates:
a) Water loss, dehydration ✅
b) Sodium loss
c) Hyperglycemia
d) Hypokalemia

Explanation: Hypernatremia usually results from water deficit rather than excess sodium.

Hyponatremia causes:
a) SIADH, water retention ✅
b) Diabetes mellitus
c) Hyperthyroidism
d) Hyperkalemia

Explanation: Low sodium from excess water or sodium loss; SIADH is common cause.

Normal serum potassium:
a) 2–3 mmol/L
b) 3.5–5 mmol/L ✅
c) 5–6 mmol/L
d) 6–7 mmol/L

Explanation: Potassium is essential for cardiac and muscle function; narrow normal range.

Hypokalemia may cause:
a) Muscle weakness, arrhythmias ✅
b) Hyperactivity
c) Bradycardia only
d) Hypertension

Explanation: Low potassium impairs action potentials → muscle fatigue, cramps, arrhythmias.

Hyperkalemia may cause:
a) Cardiac arrhythmia ✅
b) Hypotension
c) Hypoglycemia
d) Muscle spasm

Explanation: High potassium → life-threatening cardiac conduction abnormalities.

Serum calcium normal range:
a) 8.5–10.5 mg/dL ✅
b) 6–8 mg/dL
c) 11–13 mg/dL
d) 12–15 mg/dL

Explanation: Normal calcium is essential for bone, muscle, nerve, and cardiac function.

Hypercalcemia occurs in:
a) Hyperparathyroidism ✅
b) Hypothyroidism
c) Addison’s disease
d) Diabetes

Explanation: Excess parathyroid hormone increases calcium release from bones, causing hypercalcemia.

Hypocalcemia occurs in:
a) Vitamin D deficiency ✅
b) Hyperthyroidism
c) Hyperparathyroidism
d) Gout

Explanation: Vitamin D deficiency reduces calcium absorption → low serum calcium → tetany.

Serum phosphate normal range:
a) 2.5–4.5 mg/dL ✅
b) 0.5–1 mg/dL
c) 5–6 mg/dL
d) 6–8 mg/dL

Explanation: Phosphate is involved in energy metabolism (ATP) and bone formation.

Hyperphosphatemia indicates:
a) Renal failure ✅
b) Hypoparathyroidism
c) Vitamin D deficiency
d) Gout

Explanation: Impaired renal excretion leads to phosphate accumulation.

Hypophosphatemia indicates:
a) Malnutrition ✅
b) Renal failure
c) Hyperparathyroidism
d) Addison’s disease

Explanation: Low phosphate occurs in malnutrition, alcoholism, and refeeding syndrome.

Total CO₂ mainly represents:
a) Oxygen
b) Bicarbonate ✅
c) Carbonic acid
d) CO₂ in RBCs

Explanation: Total CO₂ is mostly bicarbonate (HCO₃⁻), reflecting acid-base status.

Anion gap formula:
a) Na⁺ + K⁺ – Cl⁻ – HCO₃⁻ ✅
b) Na⁺ – K⁺
c) Cl⁻ – HCO₃⁻
d) Na⁺ + Cl⁻

Explanation: Anion gap identifies unmeasured anions in metabolic acidosis.

Elevated anion gap indicates:
a) Metabolic acidosis ✅
b) Metabolic alkalosis
c) Respiratory acidosis
d) Respiratory alkalosis

Explanation: High anion gap occurs in lactic acidosis, ketoacidosis, renal failure, toxins.

Serum albumin normal range:
a) 3.5–5 g/dL ✅
b) 2–3 g/dL
c) 5–6 g/dL
d) 1–2 g/dL

Explanation: Albumin maintains oncotic pressure; synthesized in liver.

Hypoalbuminemia indicates:
a) Liver disease, malnutrition ✅
b) Dehydration
c) Hyperthyroidism
d) Diabetes

Explanation: Low albumin results from liver disease, nephrotic syndrome, malnutrition.

Serum total protein normal range:
a) 6–8 g/dL ✅
b) 4–6 g/dL
c) 8–10 g/dL
d) 5–7 g/dL

Explanation: Total protein = albumin + globulin; low levels indicate malnutrition or liver disease.

Albumin/globulin ratio normally:
a) 0.5–1 ✅
b) 1–2
c) 2–3
d) 0–0.5

Explanation: A/G ratio indicates protein balance; <1 may occur in liver disease or multiple myeloma.

Elevated AST/ALT indicates:
a) Hepatocellular injury ✅
b) Pancreatitis
c) Kidney injury
d) Muscle injury only

Explanation: AST and ALT rise in liver cell damage; ALT is more specific.

Elevated ALP/GGT indicates:
a) Cholestasis ✅
b) Hepatocellular injury
c) Pancreatitis
d) Renal disease

Explanation: ALP rises in bile obstruction; GGT confirms hepatic origin.

Serum bilirubin excreted in:
a) Urine
b) Bile ✅
c) Sweat
d) Saliva

Explanation: Conjugated bilirubin is excreted in bile into intestine; some may appear in urine.

Direct bilirubin is:
a) Conjugated ✅
b) Unconjugated
c) Free
d) Bound to albumin

Explanation: Direct bilirubin is water-soluble, conjugated in liver with glucuronic acid.

Indirect bilirubin is:
a) Unconjugated ✅
b) Conjugated
c) Water-soluble
d) Direct

Explanation: Indirect bilirubin is lipid-soluble, bound to albumin, elevated in hemolysis or impaired hepatic uptake.

Pancreatic function tests:
a) Amylase, lipase ✅
b) ALT, AST
c) Urea, creatinine
d) Sodium, potassium

Explanation: Amylase and lipase diagnose pancreatitis; lipase is more specific.

Lipase is preferred marker in pancreatitis because:
a) Shorter half-life
b) More specific for pancreas ✅
c) Less specific
d) Cheaper

Explanation: Lipase originates mainly from pancreas, remains elevated longer than amylase, and accurately reflects pancreatic injury.

Normal serum magnesium range:
a) 0.7–1.0 mmol/L ✅
b) 1.5–2.5 mmol/L
c) 0.5–0.6 mmol/L
d) 2.0–3.0 mmol/L

Explanation: Magnesium is essential for enzyme function, neuromuscular activity, and cardiac rhythm. Hypo- or hypermagnesemia can cause muscle weakness and arrhythmias.

Hypomagnesemia may cause:
a) Muscle cramps, arrhythmias ✅
b) Hyperactivity
c) Jaundice
d) Polyuria

Explanation: Low magnesium leads to neuromuscular excitability, tremors, tetany, and cardiac arrhythmias.

Hypermagnesemia may cause:
a) Hypotension, bradycardia ✅
b) Hyperactivity
c) Muscle spasm
d) Hypoglycemia

Explanation: Excess magnesium depresses neuromuscular and cardiac function, causing hypotension and arrhythmias.

Serum iron normal range (male):
a) 60–170 µg/dL ✅
b) 30–100 µg/dL
c) 100–200 µg/dL
d) 50–150 µg/dL

Explanation: Iron is essential for hemoglobin synthesis; measured to evaluate anemia types.

Serum ferritin reflects:
a) Daily iron intake
b) Body iron stores ✅
c) Hemoglobin only
d) Transferrin levels

Explanation: Ferritin correlates with total iron stores; low in iron deficiency, high in inflammation or hemochromatosis.

Total iron-binding capacity (TIBC) is:
a) Amount of iron in serum
b) Maximum iron transferrin can bind ✅
c) Iron excreted in urine
d) Free iron

Explanation: TIBC rises in iron deficiency and decreases in chronic disease.

Transferrin saturation formula:
a) (Serum iron ÷ TIBC) × 100 ✅
b) (TIBC ÷ serum iron) × 100
c) (Ferritin ÷ serum iron) × 100
d) (Serum iron ÷ ferritin) × 100

Explanation: Percentage of transferrin bound to iron; low in iron deficiency, high in iron overload.

Vitamin B12 deficiency may lead to:
a) Megaloblastic anemia ✅
b) Microcytic anemia
c) Hemolytic anemia
d) Leukemia

Explanation: B12 is required for DNA synthesis; deficiency causes megaloblastic anemia with hypersegmented neutrophils.

Folate deficiency leads to:
a) Megaloblastic anemia ✅
b) Microcytic anemia
c) Iron deficiency anemia
d) Hemolytic anemia

Explanation: Folate is also required for DNA synthesis; deficiency mirrors B12 deficiency but without neurological symptoms.

Homocysteine level is elevated in:
a) B12 or folate deficiency ✅
b) Iron deficiency
c) Hypercalcemia
d) Hypokalemia

Explanation: Deficiencies impair remethylation of homocysteine → cardiovascular risk.

Serum lactate dehydrogenase (LDH) is elevated in:
a) Hemolysis, myocardial infarction ✅
b) Hypoglycemia
c) Liver cirrhosis only
d) Renal stones

Explanation: LDH is released from damaged cells; nonspecific marker for tissue injury.

Creatine kinase (CK) is elevated in:
a) Muscle damage, myocardial infarction ✅
b) Liver disease
c) Kidney disease
d) Hypoglycemia

Explanation: CK is a marker for skeletal and cardiac muscle injury. CK-MB isoenzyme is specific for myocardial damage.

Cardiac troponins (cTnI, cTnT) are:
a) Early markers of MI ✅
b) Kidney function markers
c) Liver function markers
d) Electrolytes

Explanation: Highly sensitive and specific for myocardial infarction; rise within hours and remain elevated longer than CK-MB.

Brain natriuretic peptide (BNP) indicates:
a) Heart failure ✅
b) Kidney failure
c) Liver disease
d) Diabetes

Explanation: BNP is released from ventricular myocardium in response to volume expansion and pressure overload.

Serum amylase rises in:
a) Acute pancreatitis ✅
b) Diabetes
c) Liver failure
d) Renal stones

Explanation: Amylase catalyzes starch breakdown; rises in pancreatic or salivary gland injury.

Serum lipase rises in:
a) Pancreatitis ✅
b) Liver failure
c) Kidney failure
d) Diabetes

Explanation: Lipase is more specific than amylase for pancreatic injury; remains elevated longer.

Serum bilirubin elevation occurs in:
a) Hemolysis, liver disease, cholestasis ✅
b) Diabetes
c) Hypertension
d) Hyperkalemia

Explanation: Bilirubin accumulation causes jaundice; type depends on unconjugated (prehepatic) or conjugated (hepatic/posthepatic).

Alkaline phosphatase elevation occurs in:
a) Cholestasis, bone disease ✅
b) Pancreatitis
c) Myocardial infarction
d) Hypokalemia

Explanation: ALP is present in liver and bone; elevation occurs in bile duct obstruction or bone disorders.

Gamma-glutamyl transferase (GGT) is useful to detect:
a) Alcoholic liver disease ✅
b) Kidney failure
c) Diabetes
d) Hypocalcemia

Explanation: GGT rises in hepatic injury, especially alcohol-induced; helps confirm ALP origin.

ALT is more specific than AST for:
a) Liver injury ✅
b) Kidney injury
c) Heart disease
d) Muscle injury

Explanation: ALT predominantly found in liver; AST also present in muscle and heart.

AST/ALT ratio >2 suggests:
a) Alcoholic liver disease ✅
b) Viral hepatitis
c) Hemolysis
d) Kidney injury

Explanation: AST rises more than ALT in alcoholic hepatitis; in viral hepatitis ALT > AST.

Albumin/globulin ratio normally:
a) 1.0–2.0
b) 0.8–2.0 ✅
c) 0.5–1.0
d) 2–3

Explanation: Low A/G ratio occurs in liver disease, nephrotic syndrome, or multiple myeloma.

Hypoalbuminemia may result in:
a) Edema ✅
b) Hypercalcemia
c) Polycythemia
d) Hypernatremia

Explanation: Low albumin reduces plasma oncotic pressure → fluid leaks into interstitial spaces → edema.

Hyperalbuminemia usually occurs in:
a) Dehydration ✅
b) Liver failure
c) Nephrotic syndrome
d) Hypothyroidism

Explanation: Reduced plasma volume concentrates albumin, falsely elevating serum level.

Total serum protein is composed of:
a) Albumin + globulin ✅
b) Albumin only
c) Globulin only
d) Fibrinogen only

Explanation: Total protein = albumin + globulins; reflects nutritional and hepatic status.

Prealbumin (transthyretin) is used to assess:
a) Short-term protein status ✅
b) Long-term protein status
c) Renal function
d) Electrolytes

Explanation: Short half-life (~2 days) makes prealbumin useful for monitoring acute changes in protein nutrition.

Serum ammonia is elevated in:
a) Liver failure ✅
b) Renal failure
c) Diabetes
d) Hyperkalemia

Explanation: Liver detoxifies ammonia to urea; hepatic failure → hyperammonemia → encephalopathy.

Serum cholinesterase (pseudocholinesterase) is decreased in:
a) Liver disease ✅
b) Kidney disease
c) Diabetes
d) Hyperthyroidism

Explanation: Synthesized in liver; decreased in chronic liver disease or organophosphate poisoning.

Ceruloplasmin is a copper-carrying protein decreased in:
a) Wilson’s disease ✅
b) Hemochromatosis
c) Iron deficiency
d) Diabetes

Explanation: Low ceruloplasmin → copper accumulation in liver, brain, eyes.

Serum alpha-fetoprotein (AFP) is elevated in:
a) Hepatocellular carcinoma ✅
b) Kidney failure
c) Diabetes
d) Pancreatitis

Explanation: AFP is a tumor marker for liver cancer and germ cell tumors.

Serum C-reactive protein (CRP) indicates:
a) Acute inflammation ✅
b) Chronic kidney disease
c) Liver function
d) Electrolyte balance

Explanation: CRP rises rapidly in infection or inflammation; nonspecific marker.

Serum ferritin rises in:
a) Inflammation, iron overload ✅
b) Vitamin D deficiency
c) Hypokalemia
d) Diabetes

Explanation: Acute phase reactant; may be elevated in inflammatory or malignant conditions even if iron stores are normal.

Iron deficiency anemia shows:
a) Low serum iron, high TIBC ✅
b) High serum iron, low TIBC
c) Low serum iron, low TIBC
d) Normal iron and TIBC

Explanation: TIBC increases to maximize iron transport when body iron is low.

Hemochromatosis shows:
a) High serum iron, high ferritin ✅
b) Low serum iron, high ferritin
c) Low serum iron, low ferritin
d) Normal serum iron, low ferritin

Explanation: Genetic iron overload; iron accumulates in liver, pancreas, heart.

Vitamin D deficiency causes:
a) Rickets, osteomalacia ✅
b) Hypercalcemia
c) Nephrolithiasis
d) Hyperparathyroidism

Explanation: Vitamin D regulates calcium-phosphate balance; deficiency → defective bone mineralization.

Parathyroid hormone (PTH) increases:
a) Serum calcium ✅
b) Serum phosphate
c) Serum sodium
d) Serum potassium

Explanation: PTH mobilizes calcium from bone, increases renal calcium reabsorption, decreases phosphate reabsorption.

Hyperparathyroidism results in:
a) Hypercalcemia, hypophosphatemia ✅
b) Hypocalcemia, hyperphosphatemia
c) Hypercalcemia, hyperphosphatemia
d) Hypocalcemia, hypophosphatemia

Explanation: Excess PTH elevates calcium, decreases phosphate by renal excretion.

Hypoparathyroidism results in:
a) Hypocalcemia, hyperphosphatemia ✅
b) Hypercalcemia, hypophosphatemia
c) Hypercalcemia, hyperphosphatemia
d) Hypocalcemia, hypophosphatemia

Explanation: Deficient PTH → low calcium, phosphate retention.

Serum 25-hydroxy vitamin D is best for assessing:
a) Vitamin D status ✅
b) Calcium levels
c) Phosphate levels
d) PTH levels

Explanation: Reflects overall vitamin D from diet and sunlight exposure.

Serum 1,25-dihydroxy vitamin D reflects:
a) Active hormone level ✅
b) Storage level
c) Calcium only
d) Phosphate only

Explanation: 1,25(OH)₂D is active metabolite; regulated by PTH, phosphate, and kidney function.

Serum amylase rises in:
a) Pancreatitis ✅
b) Liver failure
c) Kidney failure
d) Diabetes

Explanation: Digestive enzyme from pancreas and salivary glands; rises early in pancreatitis.

Serum lipase is more specific than amylase for:
a) Pancreatic injury ✅
b) Liver injury
c) Kidney injury
d) Diabetes

Explanation: Lipase originates almost entirely from pancreas; remains elevated longer.

Lactate is elevated in:
a) Tissue hypoxia, sepsis ✅
b) Hyperglycemia
c) Renal failure
d) Liver disease

Explanation: Anaerobic metabolism increases lactate → metabolic acidosis in shock or hypoxia.

Arterial blood gas (ABG) normal pH:
a) 7.35–7.45 ✅
b) 7.25–7.35
c) 7.45–7.55
d) 7.20–7.30

Explanation: Acid-base balance; deviation indicates acidosis or alkalosis.

ABG normal PaCO₂:
a) 35–45 mmHg ✅
b) 25–35 mmHg
c) 45–55 mmHg
d) 55–65 mmHg

Explanation: Reflects respiratory component of acid-base balance.

ABG normal HCO₃⁻:
a) 22–26 mEq/L ✅
b) 18–22 mEq/L
c) 26–30 mEq/L
d) 30–35 mEq/L

Explanation: Reflects metabolic component of acid-base balance.

ABG metabolic acidosis shows:
a) Low pH, low HCO₃⁻ ✅
b) High pH, low HCO₃⁻
c) High pH, high HCO₃⁻
d) Low pH, high HCO₃⁻

Explanation: Loss of bicarbonate or increased acid → decreased pH and HCO₃⁻.

ABG metabolic alkalosis shows:
a) High pH, high HCO₃⁻ ✅
b) Low pH, high HCO₃⁻
c) Low pH, low HCO₃⁻
d) High pH, low HCO₃⁻

Explanation: Excess bicarbonate or loss of acid → alkalemia.

ABG respiratory acidosis shows:
a) Low pH, high PaCO₂ ✅
b) High pH, low PaCO₂
c) High pH, high PaCO₂
d) Low pH, low PaCO₂

Explanation: Hypoventilation → CO₂ retention → decreased pH.

ABG respiratory alkalosis shows:
a) High pH, low PaCO₂ ✅
b) Low pH, low PaCO₂
c) Low pH, high PaCO₂
d) High pH, high PaCO₂

Explanation: Hyperventilation → CO₂ loss → alkalemia.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Spectrophotometer principle:
a) Color change
b) Light absorption ✅
c) Fluorescence
d) Turbidity

Explanation: Spectrophotometers measure the absorbance of light by a solution at a specific wavelength to quantify analytes like glucose, bilirubin, or enzymes.

Beer’s Law in spectrophotometry states:
a) Absorbance ∝ concentration ✅
b) Absorbance ∝ square root of concentration
c) Absorbance ∝ 1/concentration
d) Absorbance ∝ log(concentration)

Explanation: Beer-Lambert law: Absorbance is directly proportional to concentration and path length of light.

Common wavelength for measuring glucose (GOD-POD method):
a) 340 nm
b) 505 nm ✅
c) 620 nm
d) 450 nm

Explanation: Glucose oxidase-peroxidase reaction produces a colored quinoneimine dye measured at 505 nm.

Flame photometer measures:
a) Enzymes
b) Electrolytes (Na⁺, K⁺, Li⁺) ✅
c) Proteins
d) Glucose

Explanation: Flame photometry detects emission of light from specific ions in a flame, used for sodium, potassium, lithium measurement.

ISE (Ion-selective electrode) measures:
a) Sodium, potassium, chloride ✅
b) Glucose only
c) Proteins only
d) Bilirubin

Explanation: ISE directly measures ion activity in serum/plasma; widely used in automated electrolyte analyzers.

Principle of centrifugation:
a) Sedimentation by gravity
b) Sedimentation by centrifugal force ✅
c) Diffusion
d) Osmosis

Explanation: Centrifugation separates components based on density differences using high-speed rotation.

Normal pH meter calibration requires:
a) One standard
b) Two or more standard buffers ✅
c) No calibration
d) Distilled water

Explanation: At least two pH buffers (e.g., pH 4 and 7 or 7 and 10) are used to ensure accuracy across the pH range.

Principle of automated biochemistry analyzer:
a) Manual titration
b) Photometry and colorimetry ✅
c) Microscopy
d) Flame emission

Explanation: Automated analyzers use photometric/colorimetric methods to measure enzyme activity, metabolites, electrolytes.

Nephelometry is used to measure:
a) Light scattered by particles ✅
b) Light absorbed
c) Turbidity only
d) Fluorescence

Explanation: Measures scattered light by antigen-antibody complexes to quantify proteins like immunoglobulins, CRP.

Turbidimetry differs from nephelometry in:
a) Measures scattered light forward ✅
b) Measures absorbed light
c) Measures fluorescence
d) Measures refractive index

Explanation: Turbidimetry measures decrease in transmitted light through a solution; nephelometry measures scattered light at angle.

Flame photometer requires which fuel?
a) Oxygen
b) Air-acetylene ✅
c) Helium
d) Hydrogen only

Explanation: Air-acetylene flame excites metal ions (Na⁺, K⁺) to emit light at characteristic wavelengths.

Biosensor principle:
a) Optical detection
b) Bioreceptor + transducer ✅
c) Centrifugation
d) Colorimetry

Explanation: Biosensor converts biochemical interaction into measurable electrical or optical signal, e.g., glucose biosensors.

Clinical chemistry analyzer measures:
a) Enzymes, electrolytes, metabolites ✅
b) Red cells only
c) White cells only
d) Platelets only

Explanation: Automated analyzers measure multiple analytes using colorimetric, enzymatic, or ISE methods.

CO₂ electrode measures:
a) pH
b) Partial pressure of CO₂ ✅
c) Oxygen
d) Electrolytes

Explanation: CO₂ diffuses through a membrane, alters pH of internal solution → converted to CO₂ partial pressure.

Clark electrode measures:
a) Oxygen in blood ✅
b) CO₂
c) pH
d) Electrolytes

Explanation: Measures oxygen via reduction at cathode; commonly used in ABG analyzers.

Clinical centrifuge used for serum separation spins at:
a) 100–500 rpm
b) 3000–5000 rpm ✅
c) 10,000 rpm
d) 50 rpm

Explanation: Serum/plasma separation requires moderate high-speed centrifugation to sediment cells.

Microplate reader is used in:
a) ELISA ✅
b) Blood smear
c) Centrifugation
d) Flame photometry

Explanation: Microplate reader detects colorimetric, fluorescent, or luminescent signals in ELISA assays.

Principle of ELISA:
a) Antigen-antibody reaction with enzyme detection ✅
b) Colorimetry only
c) Light scattering
d) Flame emission

Explanation: Enzyme-linked antibodies react with substrate → color change proportional to analyte concentration.

Coagulometer measures:
a) Prothrombin time (PT) ✅
b) Electrolytes
c) Glucose
d) Enzymes

Explanation: Detects clot formation time using mechanical or optical methods; important in coagulation tests.

Nephelometer vs turbidimeter:
a) Scattered vs transmitted light ✅
b) Color vs light
c) pH vs voltage
d) Flame vs light

Explanation: Nephelometer: light scattered → protein quantification; turbidimeter: transmitted light decrease → similar application.

Flame photometry is NOT used for:
a) Sodium
b) Potassium
c) Calcium ✅
d) Lithium

Explanation: Calcium requires atomic absorption spectroscopy; flame photometry measures Na⁺, K⁺, Li⁺.

Atomic absorption spectrophotometer (AAS) principle:
a) Absorption of light by free atoms ✅
b) Fluorescence
c) Colorimetry
d) Turbidimetry

Explanation: AAS measures specific metal ions by absorption at characteristic wavelengths.

Principle of turbidimetry:
a) Measures light blocked by precipitate ✅
b) Measures absorbed light
c) Measures scattered light
d) Measures fluorescence

Explanation: Turbidimetry quantifies concentration by loss of transmitted light.

Principle of nephelometry:
a) Measures scattered light at an angle ✅
b) Measures transmitted light
c) Measures absorbed light
d) Measures fluorescence

Explanation: Useful for quantifying proteins in serum or urine.

Centrifuge rotor types include:
a) Fixed angle, swinging bucket ✅
b) Horizontal only
c) Vertical only
d) None

Explanation: Different rotors for serum, plasma, urine, or microtubes; choice depends on sedimentation efficiency.

Blood glucose oxidase-peroxidase method produces:
a) Quinoneimine dye ✅
b) NADH
c) ATP
d) Bilirubin

Explanation: Glucose + oxygen → H₂O₂ via GOD; H₂O₂ reacts with chromogen → colored product measured at 505 nm.

Coagulation analyzers detect clot by:
a) Mechanical or optical changes ✅
b) Color only
c) Fluorescence
d) Voltage

Explanation: Mechanical detection: rotation of steel ball; optical detection: light transmission change.

Automated electrolyte analyzer commonly uses:
a) ISE ✅
b) Spectrophotometry
c) Turbidimetry
d) Nephelometry

Explanation: Measures sodium, potassium, chloride directly in serum/plasma.

Glucose biosensor uses:
a) Enzyme + transducer ✅
b) Colorimetry only
c) Flame photometry
d) Centrifugation

Explanation: Enzyme (glucose oxidase) reacts with glucose → electrical signal proportional to glucose.

Lab pipettes must be calibrated:
a) Monthly ✅
b) Yearly
c) Daily
d) Never

Explanation: Accurate pipetting is crucial; routine calibration prevents errors in biochemical assays.

Principle of Refractometer:
a) Measures light bending (refractive index) ✅
b) Absorption of light
c) Turbidity
d) Emission

Explanation: Refractive index correlates with solvent concentration, e.g., total protein, urine specific gravity.

Flame photometer error can occur due to:
a) Improper aspiration ✅
b) Correct dilution
c) Standard solution
d) Clean flame

Explanation: Errors arise from bubbles, incorrect aspiration, contamination, affecting ion measurement.

Atomic absorption spectroscopy is superior to flame photometry for:
a) Low concentration metals ✅
b) High concentration metals
c) Proteins
d) Enzymes

Explanation: AAS is more sensitive, can detect trace metals like copper, zinc, lead.

ELISA requires:
a) Antigen, antibody, enzyme, substrate ✅
b) Only antibody
c) Only antigen
d) Only enzyme

Explanation: Complete ELISA reaction requires all components for colorimetric detection.

Clinical chemistry analyzer can perform:
a) Multiple analytes simultaneously ✅
b) One test at a time
c) Only electrolytes
d) Only enzymes

Explanation: Automated analyzers increase throughput, reduce human error.

ABG analyzer measures:
a) pH, PaCO₂, PaO₂, HCO₃⁻ ✅
b) Glucose only
c) Enzymes only
d) Electrolytes only

Explanation: Provides respiratory and metabolic status; essential in critical care.

CO₂ electrode membrane is permeable to:
a) CO₂ gas ✅
b) O₂ gas
c) Na⁺
d) K⁺

Explanation: CO₂ diffuses into internal solution → pH change → measured as PaCO₂.

Clark electrode measures:
a) Dissolved oxygen ✅
b) Carbon dioxide
c) Glucose
d) pH

Explanation: Oxygen reduced at cathode → current proportional to oxygen tension.

Microplate reader can detect:
a) Absorbance, fluorescence, luminescence ✅
b) Only absorbance
c) Only fluorescence
d) Only luminescence

Explanation: Multi-mode readers allow ELISA, enzyme kinetics, nucleic acid/protein assays.

Biosensor advantage:
a) Rapid, small sample, high specificity ✅
b) Slow, large sample
c) Non-specific
d) Inaccurate

Explanation: Modern biosensors enable point-of-care testing with accuracy and convenience.

Principle of colorimeter:
a) Light absorption by colored solution ✅
b) Light scattering
c) Emission
d) Turbidity

Explanation: Measures concentration based on absorbance at specific wavelength.

Autoanalyzer reduces:
a) Manual errors ✅
b) Precision
c) Accuracy
d) Speed

Explanation: Automation improves precision, speed, and reproducibility in biochemical assays.

Quality control in clinical chemistry ensures:
a) Accuracy, precision ✅
b) Color change
c) Centrifugation
d) Turbidity

Explanation: QC uses control samples to detect errors in reagents, instruments, or techniques.

Turbidimetry vs nephelometry:
a) Turbidimetry: transmitted light; nephelometry: scattered light ✅
b) Both same
c) Both different principle
d) Both measure fluorescence

Explanation: Nephelometry is more sensitive for low concentration proteins.

Normal serum sodium:
a) 135–145 mmol/L ✅
b) 120–130
c) 150–160
d) 100–110

Explanation: Sodium is main extracellular cation; vital for osmotic balance.

Flame photometer measures Na⁺ at wavelength:
a) 589 nm ✅
b) 656 nm
c) 450 nm
d) 505 nm

Explanation: Sodium emits light at 589 nm in flame; potassium at 766 nm.

Flame photometer measures K⁺ at wavelength:
a) 766 nm ✅
b) 589 nm
c) 450 nm
d) 505 nm

Explanation: Potassium’s characteristic emission allows selective quantification.

Biosensor glucose monitor uses enzyme:
a) Glucose oxidase ✅
b) Lipase
c) Amylase
d) Hexokinase

Explanation: Most glucose biosensors use glucose oxidase, which catalyzes the oxidation of glucose to gluconic acid and hydrogen peroxide, generating an electrical signal proportional to glucose concentration.

Advantages of automated analyzers include:
a) High throughput, accuracy, precision ✅
b) Slow and laborious
c) Only for electrolytes
d) Only for enzymes

Explanation: Automated analyzers reduce human error, allow simultaneous multiple analyte measurements, and improve laboratory efficiency.

Normal potassium range in serum:
a) 3.5–5.0 mmol/L ✅
b) 2.5–3.0
c) 5.5–6.5
d) 1.0–2.0

Explanation: Potassium is the main intracellular cation; abnormal levels (hypo- or hyperkalemia) can cause cardiac arrhythmias and muscle weakness.

Normal fasting blood glucose:
a) 70–100 mg/dL ✅
b) 100–125 mg/dL
c) 126–150 mg/dL
d) 50–70 mg/dL

Explanation: Fasting blood glucose reflects baseline glucose metabolism; 70–100 mg/dL is considered normal.

Diabetes is diagnosed if fasting glucose ≥:
a) 100 mg/dL
b) 126 mg/dL ✅
c) 110 mg/dL
d) 140 mg/dL

Explanation: Fasting glucose ≥126 mg/dL on two occasions indicates diabetes mellitus.

Oral Glucose Tolerance Test (OGTT) normal 2-hour glucose:
a) <140 mg/dL ✅
b) 140–199 mg/dL
c) ≥200 mg/dL
d) 100–125 mg/dL

Explanation: 2-hour post-glucose load <140 mg/dL is normal; 140–199 mg/dL indicates impaired glucose tolerance.

Glycated hemoglobin (HbA1c) reflects:
a) 1-month average glucose
b) 2–3 months average glucose ✅
c) 1 week glucose
d) Only fasting glucose

Explanation: HbA1c is formed by non-enzymatic glycation of hemoglobin; reflects long-term glucose control.

Normal HbA1c level:
a) <5.7% ✅
b) 5.7–6.4%
c) ≥6.5%
d) >7%

Explanation: HbA1c <5.7% is normal; 5.7–6.4% indicates prediabetes; ≥6.5% indicates diabetes.

Insulin is secreted by:
a) Alpha cells
b) Beta cells ✅
c) Delta cells
d) PP cells

Explanation: Beta cells of pancreatic islets secrete insulin; alpha cells secrete glucagon.

Glucagon is secreted by:
a) Alpha cells ✅
b) Beta cells
c) Delta cells
d) PP cells

Explanation: Glucagon increases blood glucose via glycogenolysis and gluconeogenesis.

Serum cholesterol normal range:
a) <200 mg/dL ✅
b) 200–239 mg/dL
c) 240–300 mg/dL
d) 250–300 mg/dL

Explanation: Total cholesterol <200 mg/dL is desirable; elevated cholesterol is a cardiovascular risk factor.

HDL cholesterol normal:
a) >40 mg/dL ✅
b) <40 mg/dL
c) 20–30 mg/dL
d) >60 mg/dL

Explanation: HDL is protective (“good cholesterol”); low HDL increases risk of atherosclerosis.

LDL cholesterol normal:
a) <100 mg/dL ✅
b) 100–129 mg/dL
c) 130–159 mg/dL
d) 160–189 mg/dL

Explanation: LDL is atherogenic; optimal <100 mg/dL.

Triglycerides normal:
a) <150 mg/dL ✅
b) 150–199 mg/dL
c) 200–499 mg/dL
d) ≥500 mg/dL

Explanation: High triglycerides increase risk of pancreatitis and cardiovascular disease.

Liver function test includes:
a) AST, ALT, ALP, bilirubin, albumin ✅
b) Glucose only
c) Urea only
d) Electrolytes only

Explanation: LFTs assess liver injury, cholestasis, and synthetic function.

AST/ALT ratio >2 suggests:
a) Alcoholic liver disease ✅
b) Viral hepatitis
c) Hemolysis
d) Kidney disease

Explanation: AST rises more than ALT in alcohol-related liver disease.

Bilirubin is conjugated in:
a) Kidney
b) Liver ✅
c) Pancreas
d) Spleen

Explanation: Liver conjugates bilirubin with glucuronic acid to form water-soluble conjugated bilirubin.

Serum alkaline phosphatase rises in:
a) Cholestasis, bone disease ✅
b) Diabetes
c) Pancreatitis
d) Kidney failure

Explanation: ALP is elevated in bile duct obstruction, bone turnover, or liver disease.

Serum amylase rises in:
a) Acute pancreatitis ✅
b) Liver failure
c) Kidney disease
d) Hypoglycemia

Explanation: Enzyme from pancreas/salivary glands; elevated in pancreatitis.

Serum lipase is more specific than amylase for:
a) Pancreatic injury ✅
b) Liver injury
c) Kidney injury
d) Diabetes

Explanation: Lipase originates almost exclusively from pancreas; elevated longer than amylase.

Creatinine is a marker for:
a) Liver function
b) Kidney function ✅
c) Pancreatic function
d) Electrolytes

Explanation: Serum creatinine reflects renal filtration capacity; rises in renal impairment.

Urea is synthesized in:
a) Liver ✅
b) Kidney
c) Pancreas
d) Spleen

Explanation: Urea is final nitrogenous product of protein metabolism via urea cycle in liver.

Hyperuricemia may cause:
a) Gout ✅
b) Diabetes
c) Hypokalemia
d) Liver failure

Explanation: Excess uric acid crystallizes in joints → gout; may also indicate renal dysfunction.

Serum calcium normal:
a) 8.5–10.5 mg/dL ✅
b) 7.0–8.0
c) 10.5–12
d) 6–7

Explanation: Calcium is vital for bone, neuromuscular function, and coagulation.

Serum phosphate normal:
a) 2.5–4.5 mg/dL ✅
b) 1–2
c) 5–6
d) 6–7

Explanation: Phosphate is essential for energy (ATP) and bone formation.

Parathyroid hormone increases:
a) Calcium ✅
b) Phosphate
c) Sodium
d) Potassium

Explanation: PTH increases calcium via bone resorption, renal reabsorption, vitamin D activation.

Hypoparathyroidism leads to:
a) Hypocalcemia, hyperphosphatemia ✅
b) Hypercalcemia
c) Hypokalemia
d) Hypernatremia

Explanation: Low PTH reduces calcium, increases phosphate retention.

Vitamin D deficiency causes:
a) Rickets, osteomalacia ✅
b) Hypercalcemia
c) Diabetes
d) Kidney stones

Explanation: Vitamin D is needed for calcium/phosphate absorption; deficiency → defective bone mineralization.

Vitamin B12 deficiency causes:
a) Megaloblastic anemia ✅
b) Microcytic anemia
c) Hemolytic anemia
d) Leukemia

Explanation: DNA synthesis defect → megaloblastic anemia; neurological symptoms may occur.

Folate deficiency leads to:
a) Megaloblastic anemia ✅
b) Microcytic anemia
c) Hemolytic anemia
d) Leukemia

Explanation: Folate is essential for DNA synthesis; deficiency mirrors B12 deficiency but without neurological symptoms.

Homocysteine is elevated in:
a) B12 or folate deficiency ✅
b) Iron deficiency
c) Hypercalcemia
d) Hypokalemia

Explanation: Deficiencies impair remethylation of homocysteine → cardiovascular risk.

Serum ferritin indicates:
a) Body iron stores ✅
b) Daily iron intake
c) Transferrin
d) Hemoglobin only

Explanation: Ferritin correlates with total iron; low in deficiency, high in overload or inflammation.

Iron deficiency anemia shows:
a) Low serum iron, high TIBC ✅
b) High serum iron, low TIBC
c) Low serum iron, low TIBC
d) Normal iron/TIBC

Explanation: Body increases transferrin (TIBC) to maximize iron transport.

Hemochromatosis shows:
a) High serum iron, high ferritin ✅
b) Low serum iron, high ferritin
c) Low serum iron, low ferritin
d) Normal serum iron, low ferritin

Explanation: Genetic iron overload; iron deposits in organs.

CRP is a marker of:
a) Acute inflammation ✅
b) Chronic kidney disease
c) Liver function
d) Electrolytes

Explanation: CRP rises rapidly in infection/inflammation; nonspecific acute phase reactant.

ESR (erythrocyte sedimentation rate) indicates:
a) Inflammation ✅
b) Liver disease
c) Electrolyte imbalance
d) Kidney disease

Explanation: Elevated ESR reflects increased plasma proteins (fibrinogen) → faster RBC sedimentation.

Lactate is elevated in:
a) Tissue hypoxia, sepsis ✅
b) Hyperglycemia
c) Kidney failure
d) Liver disease

Explanation: Anaerobic metabolism → lactic acidosis.

Serum ammonia is elevated in:
a) Liver failure ✅
b) Kidney failure
c) Diabetes
d) Hyperkalemia

Explanation: Liver detoxifies ammonia to urea; hepatic failure → hyperammonemia → encephalopathy.

Serum alpha-fetoprotein (AFP) rises in:
a) Hepatocellular carcinoma ✅
b) Kidney failure
c) Diabetes
d) Pancreatitis

Explanation: Tumor marker for liver and germ cell tumors.

Serum ceruloplasmin is low in:
a) Wilson’s disease ✅
b) Hemochromatosis
c) Iron deficiency
d) Diabetes

Explanation: Copper-carrying protein; deficiency → copper accumulation in tissues.

Serum amylase and lipase ratio >2 suggests:
a) Salivary origin of amylase ✅
b) Pancreatic origin
c) Liver origin
d) Kidney origin

Explanation: Elevated amylase more than lipase suggests parotitis rather than pancreatitis.

Serum LDH isoenzymes: LDH1>LDH2 indicates:
a) Myocardial infarction ✅
b) Liver disease
c) Kidney failure
d) Pancreatitis

Explanation: LDH1 predominates in heart; “flip” indicates MI.

CK-MB isoenzyme indicates:
a) Cardiac muscle damage ✅
b) Liver injury
c) Kidney disease
d) Pancreatic injury

Explanation: CK-MB rises 4–6 h after MI; peaks at 24 h.

BNP indicates:
a) Heart failure ✅
b) Kidney failure
c) Liver disease
d) Diabetes

Explanation: Released by ventricular myocardium in response to volume/pressure overload.

Serum troponins are:
a) Most sensitive/specific for MI ✅
b) Electrolytes
c) Liver markers
d) Kidney markers

Explanation: Rise within hours, remain elevated longer than CK-MB.

Serum uric acid normal:
a) 3.5–7.2 mg/dL ✅
b) 1–3 mg/dL
c) 7–10 mg/dL
d) 2–5 mg/dL

Explanation: High uric acid → gout; low may occur in kidney disorders.

Serum albumin normal:
a) 3.5–5.0 g/dL ✅
b) 2.0–3.0
c) 5–6
d) 6–7

Explanation: Albumin maintains oncotic pressure and transports molecules.

Hypoalbuminemia causes:
a) Edema ✅
b) Hypernatremia
c) Hypercalcemia
d) Polycythemia

Explanation: Low oncotic pressure → fluid shifts into interstitial space.

Serum globulin normal:
a) 2.0–3.5 g/dL ✅
b) 1–2
c) 3.5–4.5
d) 4.5–5

Explanation: Includes immunoglobulins and other carrier proteins.

A/G ratio normally:
a) 1.0–2.0 ✅
b) 0.5–0.9
c) 2.0–3.0
d) 0.2–0.5

Explanation: Low ratio indicates chronic liver disease, nephrotic syndrome, or multiple myeloma.

Serum chloride normal:
a) 96–106 mmol/L ✅
b) 80–90
c) 110–120
d) 70–80

Explanation: Major extracellular anion; important in acid-base balance.

Serum bicarbonate normal:
a) 22–26 mmol/L ✅
b) 18–20
c) 28–32
d) 30–35

Explanation: Represents metabolic component of acid-base balance.

ABG normal pH:
a) 7.35–7.45 ✅
b) 7.25–7.35
c) 7.45–7.55
d) 7.20–7.30

🦠 Microbiology MCQs

Gram-positive bacteria have:
a) Thin peptidoglycan layer
b) Thick peptidoglycan layer ✅
c) Outer membrane
d) Lipopolysaccharide

Explanation: Gram-positive bacteria have a thick peptidoglycan layer that retains crystal violet during Gram staining.

Gram-negative bacteria have:
a) Thick peptidoglycan
b) Thin peptidoglycan + outer membrane ✅
c) Only peptidoglycan
d) No cell wall

Explanation: Gram-negative bacteria have thin peptidoglycan and an outer lipid membrane with LPS, giving pink color on Gram stain.

Staphylococcus aureus is:
a) Gram-negative cocci
b) Gram-positive cocci in clusters ✅
c) Gram-positive rods
d) Gram-negative rods

Explanation: S. aureus forms grape-like clusters, catalase-positive, coagulase-positive.

Streptococcus pyogenes is:
a) Gram-positive cocci in chains ✅
b) Gram-positive cocci in clusters
c) Gram-negative cocci
d) Gram-negative rods

Explanation: S. pyogenes forms chains, is beta-hemolytic, causes pharyngitis and skin infections.

Escherichia coli is:
a) Gram-positive rod
b) Gram-negative rod ✅
c) Gram-positive cocci
d) Gram-negative cocci

Explanation: E. coli is a Gram-negative rod, lactose-fermenter on MacConkey agar.

MacConkey agar is:
a) Selective for Gram-positive bacteria
b) Selective for Gram-negative bacteria ✅
c) Differential for fungi
d) Non-selective

Explanation: Contains bile salts and crystal violet; inhibits Gram-positive bacteria.

Mannitol Salt Agar (MSA) is:
a) Selective for Staphylococci ✅
b) Selective for Streptococci
c) Selective for Gram-negative
d) Selective for fungi

Explanation: High salt concentration (7.5%) inhibits most bacteria; S. aureus ferments mannitol → yellow colonies.

Chocolate agar is enriched with:
a) Blood cells
b) Hemin (X) and NAD (V) ✅
c) MacConkey
d) Sabouraud

Explanation: Used for fastidious bacteria like Haemophilus and Neisseria.

Thayer-Martin agar is used to isolate:
a) Neisseria gonorrhoeae ✅
b) E. coli
c) S. aureus
d) Candida

Explanation: Selective chocolate agar with antibiotics to suppress normal flora.

CLED agar is used for:
a) Urinary isolates ✅
b) Blood culture
c) Fecal culture
d) Fungal culture

Explanation: Cystine-Lactose-Electrolyte-Deficient agar prevents swarming of Proteus; supports urinary pathogens.

Ziehl-Neelsen stain is used for:
a) Gram-positive bacteria
b) Acid-fast bacteria (Mycobacteria) ✅
c) Fungi
d) Viruses

Explanation: Mycobacterium has mycolic acids; retains carbol fuchsin after acid-alcohol decolorization.

India ink stain is used for:
a) Cryptococcus neoformans ✅
b) Candida albicans
c) Aspergillus
d) Bacteria

Explanation: Negative staining highlights polysaccharide capsule of Cryptococcus.

Sabouraud Dextrose Agar (SDA) is used for:
a) Bacteria
b) Fungi ✅
c) Viruses
d) Parasites

Explanation: Acidic medium with dextrose supports fungal growth; inhibits bacteria.

Kirby-Bauer method tests:
a) Antibiotic susceptibility ✅
b) Blood grouping
c) Gram stain
d) Viral culture

Explanation: Disk diffusion method; zone of inhibition measured to determine susceptibility.

Anaerobic bacteria grow in:
a) Presence of oxygen
b) Absence of oxygen ✅
c) High salt
d) High sugar

Explanation: Obligate anaerobes cannot survive oxygen; require anaerobic chambers or jars.

Clostridium tetani causes:
a) Tetanus ✅
b) Botulism
c) Diptheria
d) Anthrax

Explanation: Gram-positive, spore-forming rod; produces tetanospasmin neurotoxin.

Clostridium botulinum causes:
a) Botulism ✅
b) Tetanus
c) Gas gangrene
d) Food poisoning

Explanation: Produces botulinum toxin → flaccid paralysis.

Bacillus anthracis characteristic:
a) Gram-positive rod, spore-forming ✅
b) Gram-negative cocci
c) Gram-positive cocci
d) Gram-negative rod

Explanation: Causes anthrax; non-motile, encapsulated in culture.

Listeria monocytogenes grows at:
a) 4°C ✅
b) 37°C
c) 25°C
d) 50°C

Explanation: Can survive in refrigerated foods; causes listeriosis in neonates and immunocompromised.

Vibrio cholerae grows on:
a) TCBS agar ✅
b) MacConkey
c) Blood agar
d) Chocolate agar

Explanation: Thiosulfate-Citrate-Bile salts-Sucrose agar; sucrose fermenters → yellow colonies.

Salmonella Typhi grows on:
a) XLD agar ✅
b) CLED
c) SDA
d) Mannitol salt

Explanation: Xylose-Lysine-Deoxycholate agar; produces red colonies with black centers (H2S).

Shigella grows on:
a) XLD agar ✅
b) TCBS
c) Chocolate
d) Mannitol salt

Explanation: XLD agar; red colonies without H2S.

Urease test is positive in:
a) Proteus ✅
b) E. coli
c) Salmonella
d) Shigella

Explanation: Urease hydrolyzes urea → ammonia → pink color (phenol red indicator).

Catalase test differentiates:
a) Staphylococcus (+) vs Streptococcus (-) ✅
b) Gram-positive vs Gram-negative
c) Bacillus vs Clostridium
d) E. coli vs Salmonella

Explanation: Catalase converts H₂O₂ → H₂O + O₂; bubbles indicate positive reaction.

Coagulase test detects:
a) S. aureus ✅
b) S. epidermidis
c) S. pyogenes
d) E. coli

Explanation: Converts fibrinogen → fibrin; differentiates pathogenic staph from non-pathogenic.

Oxidase test detects presence of:
a) Cytochrome c oxidase ✅
b) Catalase
c) Urease
d) Lipase

Explanation: Pseudomonas and Neisseria oxidase-positive; Enterobacteriaceae oxidase-negative.

Most common cause of urinary tract infection:
a) E. coli ✅
b) Klebsiella
c) Proteus
d) Pseudomonas

Explanation: Uropathogenic E. coli adheres to urothelium via fimbriae.

Most common cause of bacterial meningitis in adults:
a) Neisseria meningitidis ✅
b) Streptococcus pneumoniae
c) Haemophilus influenzae
d) Listeria

Explanation: N. meningitidis is Gram-negative diplococcus, common in adolescents/young adults.

Common cause of neonatal sepsis:
a) Group B Streptococcus ✅
b) E. coli
c) Listeria
d) Staph aureus

Explanation: Vertical transmission from mother; early-onset sepsis.

Bordetella pertussis causes:
a) Whooping cough ✅
b) Diphtheria
c) Tetanus
d) Influenza

Explanation: Gram-negative coccobacillus; produces pertussis toxin → paroxysmal cough.

Corynebacterium diphtheriae produces:
a) Diphtheria toxin ✅
b) Tetanospasmin
c) Botulinum toxin
d) Enterotoxin

Explanation: Exotoxin inhibits protein synthesis → pseudomembrane formation in pharynx.

Mycobacterium tuberculosis is:
a) Acid-fast rod ✅
b) Gram-negative rod
c) Gram-positive cocci
d) Spirochete

Explanation: High lipid (mycolic acid) in cell wall → acid-fast; slow-growing pathogen.

Mantoux test detects:
a) Tuberculosis infection ✅
b) Tetanus
c) Typhoid
d) Diphtheria

Explanation: Delayed-type hypersensitivity reaction to PPD (purified protein derivative).

Sabouraud agar is selective for:
a) Candida, Aspergillus ✅
b) E. coli
c) Staph
d) Salmonella

Explanation: Acidic medium favors fungal growth; bacterial growth inhibited.

Candida albicans forms:
a) Pseudohyphae ✅
b) True hyphae only
c) Spores only
d) Mycelium only

Explanation: Pseudohyphae help identify C. albicans microscopically.

Cryptococcus neoformans capsule is detected by:
a) India ink ✅
b) Gram stain
c) Ziehl-Neelsen
d) KOH mount

Explanation: Negative staining reveals clear halo around yeast cells.

Aspergillus fumigatus grows as:
a) Septate hyphae ✅
b) Non-septate
c) Yeast
d) Coccus

Explanation: Septate hyphae with acute angle branching on microscopy.

Malaria parasite detected by:
a) Blood smear ✅
b) Urine
c) Stool
d) Saliva

Explanation: Thick and thin blood films stained with Giemsa to identify Plasmodium species.

Plasmodium falciparum causes:
a) Severe malaria ✅
b) Benign malaria
c) Babesiosis
d) Toxoplasmosis

Explanation: High parasitemia; can cause cerebral malaria and multi-organ failure.

Plasmodium vivax causes:
a) Benign tertian malaria ✅
b) Cerebral malaria
c) Quartan malaria
d) Relapsing malaria

Explanation: Dormant liver hypnozoites → relapses.

Entamoeba histolytica trophozoites are:
a) Motile, phagocytose RBCs ✅
b) Non-motile
c) Yeast-like
d) Spore-forming

Explanation: Causes amebic dysentery; trophozoites in stool may contain ingested RBCs.

Giardia lamblia trophozoite shape:
a) Pear-shaped, flagellated ✅
b) Spherical
c) Spore
d) Filamentous

Explanation: Causes watery diarrhea; trophozoites adhere to small intestine.

Trichomonas vaginalis:
a) Flagellated protozoa, causes vaginitis ✅
b) Amoeba
c) Coccidian
d) Helminth

Explanation: Sexual transmission; motile trophozoites in vaginal/urine samples.

Stool ova and parasite examination detects:
a) Helminth eggs, protozoa ✅
b) Bacteria only
c) Viruses only
d) Fungi only

Explanation: Microscopic identification of parasites for diagnosis.

Blood culture bottles contain:
a) Nutrient broth + anticoagulant ✅
b) Agar only
c) Sabouraud
d) MacConkey

Explanation: Supports bacterial growth; samples incubated aerobically/anaerobically.

Kirby-Bauer disk diffusion measures:
a) Antibiotic susceptibility ✅
b) Gram staining
c) Hemolysis
d) pH

Explanation: Zone of inhibition compared with CLSI standards.

Endospore staining uses:
a) Malachite green ✅
b) Crystal violet
c) Safranin
d) India ink

Explanation: Spores resistant to staining; malachite green penetrates spores.

Helicobacter pylori detected by:
a) Urease test ✅
b) Gram stain only
c) India ink
d) Sabouraud agar

Explanation: Rapid urease test detects ammonia produced from urea by H. pylori.

Rickettsia are:
a) Obligate intracellular Gram-negative bacteria ✅
b) Gram-positive rods
c) Fungi
d) Protozoa

Explanation: Cannot survive outside host cells; transmitted via arthropod vectors.

Chlamydia trachomatis causes:
a) STIs, trachoma ✅
b) Tetanus
c) Botulism
d) Anthrax

Explanation: Obligate intracellular bacteria; diagnosed by PCR, culture, or immunofluorescence.

Legionella pneumophila causes:
a) Legionnaires’ disease ✅
b) Pneumococcal pneumonia
c) Tuberculosis
d) Diphtheria

Explanation: Gram-negative bacillus; transmitted via inhalation of contaminated water aerosols; requires buffered charcoal yeast extract (BCYE) agar.

Neisseria meningitidis virulence factor:
a) Polysaccharide capsule ✅
b) Flagella
c) Spore
d) Endotoxin only

Explanation: Capsule protects from phagocytosis; endotoxin causes meningococcemia and septic shock.

Neisseria gonorrhoeae requires:
a) Chocolate agar + CO₂ ✅
b) MacConkey agar
c) Blood agar
d) Sabouraud agar

Explanation: Fastidious Gram-negative diplococcus; grows only on enriched media with CO₂.

Bacillus cereus causes:
a) Food poisoning ✅
b) Anthrax
c) Tetanus
d) Botulism

Explanation: Produces enterotoxins → vomiting (emetic) or diarrhea (diarrheal type).

Clostridium perfringens causes:
a) Gas gangrene ✅
b) Tetanus
c) Botulism
d) Diphtheria

Explanation: Produces alpha-toxin (lecithinase); spores present in soil.

Listeria monocytogenes shape:
a) Gram-positive rod ✅
b) Gram-negative rod
c) Gram-positive cocci
d) Gram-negative cocci

Explanation: Small, facultative intracellular rod; cold-tolerant.

Helicobacter pylori is associated with:
a) Gastric ulcers, adenocarcinoma ✅
b) Hepatitis
c) Pancreatitis
d) Pneumonia

Explanation: Produces urease → neutralizes stomach acid; chronic infection → ulceration or gastric cancer.

Bordet-Gengou agar is used for:
a) Bordetella pertussis ✅
b) E. coli
c) Staph aureus
d) Salmonella

Explanation: Potato-glycerol-based agar; supports fastidious B. pertussis growth.

Viral hepatitis B is detected by:
a) HBsAg ✅
b) Anti-HCV
c) IgM anti-HAV
d) HBeAg only

Explanation: HBsAg is surface antigen; presence indicates current infection.

HIV primarily infects:
a) CD4+ T lymphocytes ✅
b) CD8+ T cells
c) B lymphocytes
d) NK cells

Explanation: HIV targets helper T cells, leading to immunodeficiency.

Epstein-Barr Virus (EBV) causes:
a) Infectious mononucleosis ✅
b) Measles
c) Chickenpox
d) Influenza

Explanation: Member of herpesvirus family; transmitted via saliva; causes lymphocytosis and atypical lymphocytes.

Cytomegalovirus infection is detected by:
a) IgM antibodies ✅
b) IgG only
c) PCR only
d) Blood culture

Explanation: CMV can cause congenital infections; IgM indicates recent infection.

Measles virus presents with:
a) Koplik spots ✅
b) Bullous lesions
c) Pustules
d) Vesicles

Explanation: Rubeola virus; RNA virus; highly contagious; vaccination prevents infection.

Mumps virus causes:
a) Parotitis ✅
b) Measles
c) Rubella
d) Chickenpox

Explanation: Paramyxovirus; spreads via respiratory droplets; swelling of parotid glands.

Rubella virus causes:
a) Congenital rubella syndrome ✅
b) Measles
c) Mumps
d) Chickenpox

Explanation: Togavirus; infection in pregnancy → congenital anomalies.

Varicella-zoster virus causes:
a) Chickenpox and shingles ✅
b) Measles
c) Rubella
d) Mumps

Explanation: Herpesvirus; primary infection → chickenpox; reactivation → shingles.

Influenza virus types:
a) A, B, C ✅
b) A, B only
c) A only
d) C only

Explanation: Influenza A causes pandemics; B is seasonal; C mild.

RSV causes:
a) Bronchiolitis in infants ✅
b) Pneumonia in adults
c) Measles
d) Mumps

Explanation: Respiratory syncytial virus; RNA virus; high risk in neonates.

Dengue virus vector:
a) Aedes mosquito ✅
b) Culex
c) Anopheles
d) Sandfly

Explanation: Flavivirus transmitted by Aedes aegypti; causes fever, hemorrhagic manifestations.

Chikungunya virus vector:
a) Aedes mosquito ✅
b) Anopheles
c) Culex
d) Sandfly

Explanation: Causes fever, arthralgia, rash; RNA virus.

Zika virus vector:
a) Aedes mosquito ✅
b) Anopheles
c) Culex
d) Sandfly

Explanation: Flavivirus; congenital infections → microcephaly.

Rabies virus is transmitted by:
a) Dog bite ✅
b) Mosquito
c) Tick
d) Food

Explanation: Lyssavirus; infects CNS; fatal if untreated.

Poliovirus causes:
a) Poliomyelitis ✅
b) Measles
c) Influenza
d) Rabies

Explanation: RNA virus; enters via fecal-oral route; infects anterior horn cells → paralysis.

Rotavirus causes:
a) Infantile diarrhea ✅
b) Pneumonia
c) Hepatitis
d) Meningitis

Explanation: Double-stranded RNA virus; fecal-oral; vaccine-preventable.

Norovirus causes:
a) Gastroenteritis ✅
b) Hepatitis
c) Pneumonia
d) Meningitis

Explanation: Highly contagious; common in outbreaks on cruise ships.

Hepatitis A virus transmission:
a) Fecal-oral ✅
b) Blood
c) Sexual
d) Airborne

Explanation: RNA virus; often self-limiting; vaccination prevents infection.

Hepatitis C virus transmission:
a) Bloodborne ✅
b) Airborne
c) Fecal-oral
d) Water

Explanation: RNA virus; chronic infection can cause cirrhosis and hepatocellular carcinoma.

Blood agar hemolysis types:
a) Alpha (green), Beta (clear), Gamma (none) ✅
b) Delta only
c) Epsilon only
d) Zeta only

Explanation: Hemolysis patterns help identify streptococcal species.

Beta-hemolytic streptococci:
a) Complete lysis of RBCs ✅
b) Partial lysis
c) No lysis
d) Green color

Explanation: Streptococcus pyogenes and agalactiae; clear zone around colonies.

Alpha-hemolytic streptococci:
a) Partial lysis → green ✅
b) Complete lysis
c) No lysis
d) Blue color

Explanation: Includes S. viridans and S. pneumoniae; greenish discoloration on blood agar.

Gamma-hemolytic streptococci:
a) No hemolysis ✅
b) Partial
c) Complete
d) Green

Explanation: Includes Enterococcus species; no change in agar color.

Mycobacterium leprae causes:
a) Leprosy ✅
b) Tuberculosis
c) Typhoid
d) Diphtheria

Explanation: Obligate intracellular acid-fast bacillus; cannot be cultured in vitro.

Syphilis causative agent:
a) Treponema pallidum ✅
b) Borrelia
c) Leptospira
d) Chlamydia

Explanation: Spirochete; dark-field microscopy and serology used for diagnosis.

Borrelia burgdorferi causes:
a) Lyme disease ✅
b) Syphilis
c) Leptospirosis
d) Rocky Mountain spotted fever

Explanation: Spirochete; transmitted via Ixodes tick.

Leptospira interrogans causes:
a) Leptospirosis ✅
b) Lyme disease
c) Syphilis
d) Relapsing fever

Explanation: Spirochete; zoonotic; transmitted via contaminated water/urine.

Rocky Mountain spotted fever is caused by:
a) Rickettsia rickettsii ✅
b) Rickettsia typhi
c) Chlamydia
d) Mycoplasma

Explanation: Tick-borne rickettsial infection; rash and fever.

Mycoplasma pneumoniae lacks:
a) Cell wall ✅
b) Nucleus
c) Ribosome
d) DNA

Explanation: Wall-less bacterium; resistant to beta-lactams; causes atypical pneumonia.

Pneumocystis jirovecii infection:
a) Pneumonia in immunocompromised ✅
b) GI infection
c) Skin infection
d) CNS infection

Explanation: Opportunistic fungus; diagnosed via silver stain or PCR.

Aspergillus fumigatus produces:
a) Septate hyphae, acute angle branching ✅
b) Non-septate
c) Yeast
d) Coccus

Explanation: Pulmonary infections in immunocompromised patients.

Cryptosporidium causes:
a) Diarrhea, especially in immunocompromised ✅
b) Pneumonia
c) Meningitis
d) Skin infection

Explanation: Protozoan; acid-fast oocysts seen in stool.

Toxoplasma gondii infection detected by:
a) IgM, IgG antibodies ✅
b) Stool examination
c) Blood culture
d) Urine culture

Explanation: Congenital and immunocompromised infection; cats are definitive hosts.

Giardia lamblia trophozoites are:
a) Flagellated, pear-shaped ✅
b) Round
c) Non-flagellated
d) Ciliated

Explanation: Cause watery diarrhea; adheres to small intestine.

Trichuris trichiura causes:
a) Whipworm infection ✅
b) Hookworm
c) Ascaris
d) Strongyloides

Explanation: Helminth; eggs in stool; infection via soil-transmitted helminth route.

Enterobius vermicularis causes:
a) Pinworm infection ✅
b) Hookworm
c) Ascaris
d) Trichuris

Explanation: Fecal-oral transmission; perianal itching; Scotch tape test.

Ancylostoma duodenale causes:
a) Hookworm anemia ✅
b) Whipworm
c) Pinworm
d) Ascaris

Explanation: Larvae penetrate skin; adult worms feed on intestinal blood.

Ascaris lumbricoides causes:
a) Roundworm infection ✅
b) Hookworm
c) Pinworm
d) Trichuris

Explanation: Large intestinal roundworm; causes malnutrition and intestinal obstruction.

Schistosoma mansoni eggs:
a) Lateral spine ✅
b) Terminal spine
c) No spine
d) Polar plugs

Explanation: Blood fluke; causes intestinal/hepatic schistosomiasis.

Schistosoma haematobium eggs:
a) Terminal spine ✅
b) Lateral spine
c) No spine
d) Polar plugs

Explanation: Causes urinary schistosomiasis; hematuria common.

Naegleria fowleri causes:
a) Primary amoebic meningoencephalitis ✅
b) Diarrhea
c) Pneumonia
d) Skin infection

Explanation: Free-living amoeba; infects via nasal mucosa; fatal CNS infection.

Acanthamoeba causes:
a) Keratitis, encephalitis ✅
b) Diarrhea
c) Pneumonia
d) Skin infection

Explanation: Opportunistic; contaminated water; affects contact lens wearers.

Entamoeba histolytica trophozoite contains:
a) Phagocytosed RBCs ✅
b) Cilia
c) Flagella
d) Spore

Explanation: Pathogenic form phagocytoses RBCs; causes amoebic dysentery.

Entamoeba histolytica cyst has:
a) 4 nuclei ✅
b) 1 nucleus
c) 2 nuclei
d) 8 nuclei

Explanation: Mature cyst has 4 nuclei; infective stage; resistant to stomach acid.

Giardia lamblia cysts are:
a) Quadrinucleate ✅
b) Binarucleate
c) Octonucleate
d) Single nucleate

Explanation: Infective cyst stage; survives in water; causes watery diarrhea.

Giardia lamblia trophozoites:
a) Pear-shaped, flagellated ✅
b) Round, ciliated
c) Spore-like
d) Amoeboid

Explanation: Adheres to small intestine; causes malabsorption and greasy stools.

Cryptosporidium parvum causes:
a) Severe diarrhea in immunocompromised ✅
b) Pneumonia
c) Keratitis
d) Meningitis

Explanation: Protozoan; acid-fast oocysts in stool; waterborne outbreaks.

Toxoplasma gondii is transmitted by:
a) Cat feces ✅
b) Mosquito
c) Water
d) Food only

Explanation: Cats are definitive hosts; congenital infection via transplacental transmission.

Plasmodium falciparum causes:
a) Severe malaria ✅
b) Benign malaria
c) Relapsing malaria
d) Quartan malaria

Explanation: High parasitemia; may cause cerebral malaria; ring forms in RBCs.

Plasmodium vivax causes:
a) Benign tertian malaria ✅
b) Severe malaria
c) Quartan malaria
d) Relapsing malaria

Explanation: Dormant liver hypnozoites → relapses; enlarged RBCs.

Plasmodium malariae causes:
a) Quartan malaria ✅
b) Tertian malaria
c) Cerebral malaria
d) Relapsing malaria

Explanation: 72-hour fever cycle; less severe than P. falciparum.

Plasmodium ovale causes:
a) Tertian malaria ✅
b) Quartan malaria
c) Cerebral malaria
d) None

Explanation: Rare; dormant hypnozoites → relapses; infects RBCs.

Babesia microti is transmitted by:
a) Ixodes tick ✅
b) Anopheles
c) Aedes
d) Sandfly

Explanation: Protozoan parasite; intraerythrocytic; causes hemolytic anemia.

Leishmania donovani causes:
a) Visceral leishmaniasis (Kala-azar) ✅
b) Cutaneous leishmaniasis
c) Mucocutaneous leishmaniasis
d) Malaria

Explanation: Sandfly vector; infects macrophages; hepatosplenomegaly.

Leishmania tropica causes:
a) Cutaneous leishmaniasis ✅
b) Visceral leishmaniasis
c) Mucocutaneous
d) Malaria

Explanation: Localized skin lesions; sandfly transmission.

Trichomonas vaginalis trophozoite:
a) Flagellated ✅
b) Amoeboid
c) Ciliated
d) Non-motile

Explanation: Causes vaginitis; motile trophozoites in vaginal discharge.

Trypanosoma brucei causes:
a) African sleeping sickness ✅
b) Chagas disease
c) Malaria
d) Leishmaniasis

Explanation: Tsetse fly vector; neurological symptoms; extracellular parasite.

Trypanosoma cruzi causes:
a) Chagas disease ✅
b) African sleeping sickness
c) Malaria
d) Leishmaniasis

Explanation: Reduviid bug vector; intracellular amastigotes; chronic cardiomyopathy.

Schistosoma mansoni eggs:
a) Lateral spine ✅
b) Terminal spine
c) No spine
d) Polar plugs

Explanation: Causes intestinal/hepatic schistosomiasis; eggs in stool.

Schistosoma haematobium eggs:
a) Terminal spine ✅
b) Lateral spine
c) No spine
d) Polar plugs

Explanation: Causes urinary schistosomiasis; eggs in urine; hematuria common.

Fasciola hepatica causes:
a) Liver fluke infection ✅
b) Lung fluke
c) Intestinal fluke
d) Blood fluke

Explanation: Sheep liver fluke; humans ingest metacercariae on water plants; hepatomegaly.

Clonorchis sinensis causes:
a) Bile duct infection ✅
b) Liver parenchyma
c) Lung
d) Intestine

Explanation: Chinese liver fluke; ingestion of undercooked fish; cholangitis risk.

Taenia solium causes:
a) Cysticercosis ✅
b) Ascariasis
c) Hookworm
d) Trichuriasis

Explanation: Ingestion of eggs → cysticercosis; larvae encyst in CNS or muscles.

Taenia saginata causes:
a) Beef tapeworm ✅
b) Pork tapeworm
c) Fish tapeworm
d) Hookworm

Explanation: Usually asymptomatic; adult worm in intestine.

Diphyllobothrium latum causes:
a) Fish tapeworm infection ✅
b) Pork tapeworm
c) Beef tapeworm
d) Liver fluke

Explanation: Largest tapeworm; vitamin B12 deficiency; from undercooked freshwater fish.

Enterobius vermicularis causes:
a) Pinworm infection ✅
b) Hookworm
c) Ascaris
d) Trichuris

Explanation: Perianal itching; Scotch tape test for eggs.

Ancylostoma duodenale causes:
a) Hookworm infection ✅
b) Whipworm
c) Pinworm
d) Roundworm

Explanation: Larvae penetrate skin → anemia from intestinal blood loss.

Ascaris lumbricoides infective stage:
a) Egg with larva inside ✅
b) Free larvae
c) Adult worm
d) Cyst

Explanation: Ingested embryonated egg → intestine → larvae migrate → adult worm.

Strongyloides stercoralis infective stage:
a) Filariform larva ✅
b) Egg
c) Adult worm
d) Cyst

Explanation: Penetrates skin; can cause hyperinfection in immunocompromised.

Trichuris trichiura infective stage:
a) Embryonated egg ✅
b) Larvae
c) Adult worm
d) Cyst

Explanation: Soil-transmitted helminth; adults in cecum; eggs in stool.

Echinococcus granulosus causes:
a) Hydatid disease ✅
b) Cysticercosis
c) Ascariasis
d) Hookworm

Explanation: Dog tapeworm; humans ingest eggs; larval cysts in liver/lungs.

Microfilariae of Wuchereria bancrofti found in:
a) Peripheral blood ✅
b) Urine
c) Stool
d) CSF

Explanation: Transmitted by Culex mosquitoes; nocturnal periodicity; causes lymphatic filariasis.

Brugia malayi causes:
a) Lymphatic filariasis ✅
b) Onchocerciasis
c) Loiasis
d) Ascariasis

Explanation: Vector: Mansonia mosquito; causes chronic lymphedema.

Loa loa microfilariae found in:
a) Peripheral blood ✅
b) Stool
c) CSF
d) Urine

Explanation: Eye worm; transmitted by Chrysops fly.

Onchocerca volvulus causes:
a) River blindness ✅
b) Lymphatic filariasis
c) Loiasis
d) Elephantiasis

Explanation: Transmitted by blackfly; microfilariae invade skin and eyes.

Trichinella spiralis infective stage:
a) Encysted larvae in meat ✅
b) Eggs
c) Adult worm
d) Free larvae

Explanation: Causes trichinosis; undercooked pork; larvae migrate to muscles.

Strongyloides stercoralis diagnosis:
a) Stool examination for larvae ✅
b) Blood culture
c) Urine examination
d) Skin smear

Explanation: Larvae detected via direct stool smear or Baermann technique.

Giardia lamblia diagnosis:
a) Stool microscopy for cysts/trophozoites ✅
b) Blood culture
c) Urine
d) CSF

Explanation: Trophozoites or cysts seen in wet mount; ELISA available.

Entamoeba histolytica diagnosis:
a) Stool microscopy ✅
b) Blood culture
c) Urine
d) CSF

Explanation: Trophozoites with RBCs or cysts; PCR/antigen detection also used.

Plasmodium diagnosis:
a) Thick and thin blood smear ✅
b) Stool
c) Urine
d) CSF

Explanation: Thick smear → sensitive; thin smear → species identification; Giemsa stain.

Trypanosoma brucei diagnosis:
a) Blood smear ✅
b) Stool
c) Urine
d) CSF

Explanation: Parasitemia; in late stage, lumbar puncture to detect CNS invasion.

Leishmania diagnosis:
a) Bone marrow/spleen aspirate for amastigotes ✅
b) Blood smear
c) Stool
d) Urine

Explanation: Intracellular amastigotes in macrophages; PCR and serology available.

Cryptosporidium diagnosis:
a) Stool acid-fast stain ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Modified Ziehl-Neelsen stain highlights oocysts; ELISA or PCR also used.

Toxoplasma gondii diagnosis:
a) Serology (IgM, IgG) ✅
b) Stool
c) Urine
d) Blood culture

Explanation: IgM → recent infection; IgG → past exposure; PCR for congenital infection.

Schistosoma mansoni diagnosis:
a) Stool examination for eggs ✅
b) Blood smear
c) Urine
d) Skin smear

Explanation: Lateral spine eggs detected in stool; serology aids diagnosis.

Schistosoma haematobium diagnosis:
a) Urine microscopy ✅
b) Stool
c) Blood
d) CSF

Explanation: Terminal spine eggs in urine; hematuria is a key symptom.

Fasciola hepatica diagnosis:
a) Stool eggs ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Large operculated eggs; ELISA can detect antibodies.

Clonorchis sinensis diagnosis:
a) Stool eggs ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Bile duct fluke; eggs operculated with shoulders.

Taenia solium diagnosis:
a) Stool for eggs/proglottids ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Cysticercosis requires imaging/serology; intestinal infection via stool.

Taenia saginata diagnosis:
a) Stool for eggs/proglottids ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Adult worms in intestine; eggs indistinguishable from T. solium.

Enterobius vermicularis diagnosis:
a) Scotch tape test ✅
b) Blood smear
c) Urine
d) CSF

Explanation: Eggs laid perianally; visualized on adhesive tape in morning.

Wuchereria bancrofti diagnosis:
a) Peripheral blood smear (night) ✅
b) Stool
c) Urine
d) CSF

Explanation: Microfilariae exhibit nocturnal periodicity; Giemsa-stained blood smear used.

🦠 Virology & Mycology

Human papillomavirus (HPV) causes:
a) Cervical cancer, warts ✅
b) Measles
c) Mumps
d) Rubella

Explanation: DNA virus; high-risk types 16 & 18 → cervical cancer; low-risk types → warts.

HPV is detected by:
a) PCR, Pap smear ✅
b) ELISA only
c) Blood culture
d) Stool test

Explanation: PCR detects viral DNA; Pap smear identifies cervical dysplasia.

Herpes simplex virus type 1 (HSV-1) causes:
a) Oral lesions ✅
b) Genital lesions
c) Chickenpox
d) Measles

Explanation: DNA virus; vesicular lesions on lips; latent in trigeminal ganglia.

HSV-2 mainly causes:
a) Genital herpes ✅
b) Oral lesions
c) Chickenpox
d) Measles

Explanation: DNA virus; transmitted sexually; latent in sacral ganglia.

Varicella-zoster virus primary infection:
a) Chickenpox ✅
b) Shingles
c) Measles
d) Rubella

Explanation: Herpesvirus; primary infection → varicella; reactivation → shingles.

Shingles presents as:
a) Painful dermatomal rash ✅
b) Fever only
c) Oral ulcers
d) Generalized maculopapular rash

Explanation: Reactivation of VZV in dorsal root ganglia; unilateral vesicular rash.

Epstein-Barr Virus (EBV) is associated with:
a) Mononucleosis, Burkitt lymphoma ✅
b) Measles
c) Mumps
d) Rabies

Explanation: DNA virus; infects B lymphocytes; heterophile antibody test (Monospot) used.

Cytomegalovirus (CMV) causes:
a) Congenital infections, mononucleosis ✅
b) Chickenpox
c) Hepatitis A
d) Polio

Explanation: Herpesvirus; transmitted via body fluids; immunocompromised at risk.

Hepatitis B virus structure:
a) DNA virus, enveloped ✅
b) RNA virus
c) Non-enveloped DNA virus
d) RNA virus, non-enveloped

Explanation: Hepadnavirus; partially double-stranded DNA; causes chronic hepatitis.

Hepatitis C virus structure:
a) RNA virus, enveloped ✅
b) DNA virus
c) RNA virus, non-enveloped
d) Retrovirus

Explanation: Flavivirus; bloodborne; chronic infection → cirrhosis, HCC.

HIV belongs to:
a) Retroviridae ✅
b) Herpesviridae
c) Flaviviridae
d) Adenoviridae

Explanation: RNA virus; reverse transcriptase converts RNA → DNA; infects CD4+ T cells.

Rabies virus is:
a) RNA virus, bullet-shaped ✅
b) DNA virus
c) RNA virus, icosahedral
d) Retrovirus

Explanation: Lyssavirus; infects CNS; transmitted via bite of infected animals.

Influenza virus has:
a) Segmented RNA genome ✅
b) DNA genome
c) Non-segmented RNA
d) Retrovirus genome

Explanation: Orthomyxovirus; segmented negative-sense RNA; antigenic drift/shift → epidemics.

Measles virus belongs to:
a) Paramyxoviridae ✅
b) Flaviviridae
c) Herpesviridae
d) Retroviridae

Explanation: RNA virus; causes fever, rash, Koplik spots; highly contagious.

Mumps virus belongs to:
a) Paramyxoviridae ✅
b) Flaviviridae
c) Retroviridae
d) Herpesviridae

Explanation: RNA virus; infects parotid glands; vaccine-preventable.

Rubella virus belongs to:
a) Togaviridae ✅
b) Flaviviridae
c) Retroviridae
d) Paramyxoviridae

Explanation: RNA virus; mild disease; infection in pregnancy → congenital rubella syndrome.

Rotavirus causes:
a) Infantile gastroenteritis ✅
b) Pneumonia
c) Hepatitis
d) Meningitis

Explanation: dsRNA virus; fecal-oral transmission; vaccine-preventable.

Norovirus causes:
a) Gastroenteritis outbreaks ✅
b) Hepatitis
c) Pneumonia
d) Skin infection

Explanation: RNA virus; highly contagious; cruise ship outbreaks common.

Adenovirus causes:
a) Conjunctivitis, respiratory infections ✅
b) Hepatitis
c) Gastroenteritis only
d) CNS infection

Explanation: DNA virus; transmitted via respiratory and fecal-oral route.

Parvovirus B19 causes:
a) Erythema infectiosum (Fifth disease) ✅
b) Measles
c) Rubella
d) Mumps

Explanation: ssDNA virus; mild rash in children; can cause aplastic crisis in sickle cell patients.

Human herpesvirus 6 (HHV-6) causes:
a) Roseola infantum ✅
b) Measles
c) Rubella
d) Chickenpox

Explanation: DNA virus; high fever followed by rash in infants.

Candida albicans morphology:
a) Yeast + pseudohyphae ✅
b) True hyphae only
c) Spore only
d) Coccus

Explanation: Dimorphic fungus; causes thrush, candidiasis; germ tube positive.

Candida diagnosis:
a) Germ tube test, culture ✅
b) Blood culture only
c) Stool
d) Urine

Explanation: Germ tube formation within 2–3 hours at 37°C indicates C. albicans.

Cryptococcus neoformans is:
a) Encapsulated yeast ✅
b) Mould
c) Dimorphic fungus
d) Hyphal fungus

Explanation: Opportunistic pathogen; causes meningitis in immunocompromised; India ink stain shows capsule.

Cryptococcus diagnosis:
a) India ink, culture, antigen test ✅
b) Blood smear
c) Stool
d) Urine

Explanation: Encapsulated yeast visualized in CSF; latex agglutination detects antigen.

Aspergillus fumigatus morphology:
a) Septate hyphae, acute angle branching ✅
b) Non-septate
c) Yeast
d) Spore only

Explanation: Causes pulmonary infections, allergic bronchopulmonary aspergillosis; immunocompromised risk.

Aspergillus diagnosis:
a) Culture on Sabouraud agar ✅
b) Blood smear
c) Stool
d) Urine

Explanation: Septate hyphae with acute branching on KOH mount; culture confirms species.

Mucor spp. morphology:
a) Broad, non-septate hyphae, right-angle branching ✅
b) Septate hyphae
c) Yeast
d) Spore only

Explanation: Causes mucormycosis; risk in diabetic ketoacidosis; angioinvasive.

Mucor diagnosis:
a) KOH mount, culture ✅
b) Blood smear
c) Stool
d) Urine

Explanation: Rapidly growing non-septate hyphae; culture confirms genus.

Dermatophytes cause:
a) Tinea infections ✅
b) Candida
c) Aspergillus
d) Mucor

Explanation: Keratinophilic fungi; infect skin, hair, nails; Trichophyton, Microsporum, Epidermophyton.

Microsporum causes:
a) Hair and skin infections ✅
b) Nails only
c) Oral infections
d) Systemic infection

Explanation: Fluoresces under Wood’s lamp; causes ringworm (tinea).

Trichophyton causes:
a) Skin, nail, hair infections ✅
b) Respiratory
c) CNS
d) Blood infections

Explanation: Common dermatophyte; tinea pedis, capitis, corporis.

Epidermophyton causes:
a) Skin and nail infections ✅
b) Hair
c) Oral
d) CNS

Explanation: No hair invasion; causes tinea corporis, tinea cruris.

Candida tropicalis causes:
a) Opportunistic infections in neutropenic patients ✅
b) Oral thrush only
c) Skin only
d) CNS only

Explanation: Common in hospitalized immunocompromised patients; bloodstream infections.

Candida krusei:
a) Resistant to fluconazole ✅
b) Sensitive to all antifungals
c) Causes only oral infections
d) Causes systemic infections

Explanation: Important in antifungal resistance; bloodstream infections in neutropenia.

Aspergillus flavus produces:
a) Aflatoxins ✅
b) Mycotoxins only
c) Steroids
d) None

Explanation: Contaminates grains/nuts; hepatotoxic, carcinogenic.

Histoplasma capsulatum causes:
a) Pulmonary histoplasmosis ✅
b) Cutaneous infection only
c) Oral infection
d) CNS only

Explanation: Dimorphic fungus; inhaled spores → lung infection; endemic in Ohio/Mississippi river valleys.

Histoplasma diagnosis:
a) Culture, antigen detection ✅
b) Blood smear only
c) Stool
d) Urine

Explanation: Yeast form in tissue; antigen detection in urine/blood.

Coccidioides immitis causes:
a) Valley fever ✅
b) Pulmonary TB
c) Skin infection only
d) Oral infection

Explanation: Dimorphic fungus; inhaled arthroconidia → pulmonary infection; endemic in southwestern USA.

Blastomyces dermatitidis causes:
a) Pulmonary and skin lesions ✅
b) Oral only
c) CNS only
d) Urinary infection

Explanation: Dimorphic fungus; broad-based budding yeast in tissue; endemic in North America.

Sporothrix schenckii causes:
a) Sporotrichosis (rose gardener’s disease) ✅
b) Pulmonary infection
c) CNS infection
d) Oral infection

Explanation: Dimorphic fungus; enters via skin trauma; nodular lymphangitis.

Pneumocystis jirovecii causes:
a) Pneumonia in immunocompromised ✅
b) Skin infection
c) GI infection
d) Urinary infection

Explanation: Opportunistic fungus; silver stain highlights cysts; HIV patients at risk.

Malassezia furfur causes:
a) Pityriasis versicolor ✅
b) Oral thrush
c) Pulmonary infection
d) CNS infection

Explanation: Lipophilic yeast; causes hypopigmented or hyperpigmented macules on skin.

Microsporum audouinii diagnosis:
a) Wood’s lamp fluorescence ✅
b) Blood smear
c) Urine
d) Stool

Explanation: Fluoresces green; causes tinea capitis in children.

Trichophyton rubrum diagnosis:
a) Culture on Sabouraud agar ✅
b) Blood smear
c) Stool
d) Urine

Explanation: Most common dermatophyte worldwide; nail and skin infections.

Aspergillus niger causes:
a) Otomycosis, black mold infection ✅
b) Oral thrush
c) Skin only
d) CNS only

Explanation: Opportunistic pathogen; forms black colonies; common in ear infections.

Rhizopus oryzae causes:
a) Rhinocerebral mucormycosis ✅
b) Cutaneous candidiasis
c) Oral thrush
d) Histoplasmosis

Explanation: Non-septate hyphae; diabetic ketoacidosis patients are high risk.

Candida glabrata:
a) Resistant to azoles ✅
b) Sensitive to all antifungals
c) Causes only oral thrush
d) Causes only skin infections

Explanation: Emerging opportunistic pathogen; bloodstream infections.

Fusarium spp. causes:
a) Keratitis, systemic infection in immunocompromised ✅
b) Oral thrush
c) Pneumonia only
d) Cutaneous only

Explanation: Septate hyphae; often from plant material; resistant to many antifungals.

Dermatophyte culture media:
a) Sabouraud dextrose agar ✅
b) Blood agar
c) Chocolate agar
d) MacConkey agar

Explanation: Supports fungal growth; low pH inhibits bacterial contamination.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Glucose is measured in clinical biochemistry using:
a) Glucose oxidase-peroxidase method ✅
b) ELISA
c) PCR
d) Western blot

Explanation: Enzymatic method; glucose oxidase converts glucose → gluconic acid + H₂O₂; H₂O₂ reacts with chromogen for colorimetric detection.

Cholesterol measurement uses:
a) Enzymatic colorimetric method ✅
b) Flame photometry
c) ELISA
d) PCR

Explanation: Cholesterol esterase + cholesterol oxidase produce H₂O₂ → reacts with chromogen; absorbance proportional to cholesterol.

Triglycerides are measured using:
a) Lipase + glycerol kinase method ✅
b) Glucose oxidase
c) ELISA
d) Flame photometry

Explanation: Triglycerides hydrolyzed → glycerol → measured enzymatically; colorimetric detection.

Serum urea is estimated by:
a) Diacetyl monoxime method ✅
b) Benedict’s test
c) ELISA
d) PCR

Explanation: Urea reacts with diacetyl monoxime → colored complex; absorbance measured spectrophotometrically.

Serum creatinine estimation uses:
a) Jaffe reaction ✅
b) Biuret test
c) Benedict’s test
d) Folin method

Explanation: Creatinine reacts with picric acid in alkaline medium → red-orange complex; proportional to concentration.

Bilirubin measurement in LFT:
a) Diazo method ✅
b) Jaffe reaction
c) Benedict’s test
d) Glucose oxidase

Explanation: Bilirubin reacts with diazotized sulfanilic acid → azobilirubin; direct and total bilirubin measured.

Serum proteins are estimated by:
a) Biuret method ✅
b) Jaffe method
c) Benedict’s test
d) Folin method

Explanation: Peptide bonds react with Cu²⁺ in alkaline medium → violet color; proportional to protein.

Albumin is measured by:
a) Bromocresol green (BCG) dye-binding method ✅
b) Biuret method
c) Jaffe reaction
d) Folin method

Explanation: Albumin binds BCG dye → color change; absorbance at 630 nm.

Enzyme ALT is measured using:
a) Reitman-Frankel method ✅
b) Biuret method
c) Jaffe reaction
d) Folin method

Explanation: Alanine transaminase converts alanine → pyruvate; pyruvate reacts with 2,4-dinitrophenylhydrazine → color change.

AST estimation uses:
a) Reitman-Frankel method ✅
b) Biuret method
c) Jaffe reaction
d) Folin method

Explanation: Aspartate transaminase converts aspartate → oxaloacetate; oxaloacetate reacts with DNPH → colored complex.

ALP enzyme measurement uses:
a) p-nitrophenyl phosphate method ✅
b) Biuret method
c) Jaffe reaction
d) Glucose oxidase

Explanation: ALP hydrolyzes p-nitrophenyl phosphate → p-nitrophenol (yellow color); absorbance measured at 405 nm.

Amylase estimation uses:
a) Starch-iodine method ✅
b) Biuret method
c) Jaffe reaction
d) Folin method

Explanation: Amylase hydrolyzes starch → reduced color intensity with iodine; proportional to enzyme activity.

Lipase enzyme estimation uses:
a) Colorimetric titration of fatty acids ✅
b) Biuret method
c) Jaffe reaction
d) Benedict’s test

Explanation: Lipase hydrolyzes triglycerides → free fatty acids; titrated or colorimetric method used.

Clinical chemistry automation includes:
a) Photometric, potentiometric, immunoassay analyzers ✅
b) Blood culture only
c) PCR only
d) Hematology only

Explanation: Automated analyzers increase accuracy, reduce human error, and handle large sample volume.

Spectrophotometer principle:
a) Absorbance of light by colored solution ✅
b) Fluorescence
c) Chromatography
d) Centrifugation

Explanation: Measures absorbance at specific wavelength; Beer-Lambert law used for concentration.

Flame photometer measures:
a) Na⁺, K⁺, Li⁺ ions ✅
b) Glucose
c) Bilirubin
d) Enzymes

Explanation: Flame excites metal ions → emission of light at characteristic wavelength; intensity proportional to concentration.

Electrolytes measured by:
a) Ion-selective electrodes (ISE) ✅
b) Flame photometry
c) ELISA
d) PCR

Explanation: ISE uses membrane selective for specific ion; potential difference measured.

Blood gas analyzer measures:
a) pH, pO₂, pCO₂ ✅
b) Glucose only
c) Electrolytes only
d) Proteins

Explanation: Electrodes measure hydrogen ion, oxygen, and carbon dioxide partial pressures; essential in ICU.

Microplate reader is used for:
a) ELISA, colorimetric assays ✅
b) Blood culture
c) Hematology
d) PCR

Explanation: Measures optical density of microplate wells; high-throughput detection.

Centrifuge principle:
a) Sedimentation under centrifugal force ✅
b) Diffusion
c) Filtration
d) Electrophoresis

Explanation: Separates components by density; used for serum/plasma separation.

PCR in microbiology is used for:
a) Detection of microbial DNA/RNA ✅
b) Culture only
c) ELISA only
d) Hematology

Explanation: Amplifies specific nucleic acid sequences; highly sensitive and specific.

ELISA principle:
a) Antigen-antibody reaction with enzyme-linked detection ✅
b) DNA amplification
c) Light scattering
d) Filtration

Explanation: Color change proportional to antigen/antibody concentration; widely used in serology.

Agar plate culture is used for:
a) Isolation of bacteria/fungi ✅
b) Blood gas analysis
c) Hematology
d) PCR

Explanation: Solid medium supports growth and colony morphology identification.

Chocolate agar is enriched with:
a) Hemin (X) and NAD (V) ✅
b) Only glucose
c) Only peptone
d) Agar only

Explanation: Supports growth of fastidious bacteria like Haemophilus and Neisseria.

MacConkey agar is selective for:
a) Gram-negative bacteria ✅
b) Gram-positive bacteria
c) Yeast
d) All microbes

Explanation: Bile salts and crystal violet inhibit Gram-positive; lactose fermentation differentiates coliforms.

Sabouraud dextrose agar is used for:
a) Fungal culture ✅
b) Bacteria only
c) Viral culture
d) Blood culture

Explanation: Acidic pH and dextrose support fungal growth; inhibits bacterial contamination.

Blood culture bottles contain:
a) Enriched broth with resins/anticoagulant ✅
b) Agar only
c) Saline only
d) Water

Explanation: Supports growth of aerobic/anaerobic bacteria; resins neutralize antibiotics.

Kirby-Bauer test measures:
a) Antibiotic sensitivity ✅
b) Bacterial growth only
c) Hemolysis
d) Fungal growth

Explanation: Disk diffusion; zone of inhibition measured; standardized CLSI method.

Gram stain principle:
a) Cell wall differences (peptidoglycan) ✅
b) DNA detection
c) RNA detection
d) Enzyme reaction

Explanation: Gram-positive → purple (thick peptidoglycan); Gram-negative → pink (thin peptidoglycan).

Acid-fast stain detects:
a) Mycobacteria ✅
b) Gram-negative bacteria
c) Yeast
d) Viruses

Explanation: Mycolic acid in cell wall retains carbol fuchsin; Ziehl-Neelsen or Kinyoun method.

India ink stain detects:
a) Cryptococcus neoformans capsule ✅
b) Bacteria
c) Yeast
d) RBC

Explanation: Capsule appears as clear halo; negative staining technique.

Lactophenol cotton blue stain:
a) Fungal hyphae visualization ✅
b) Bacterial cell wall
c) RBC
d) Viral capsid

Explanation: Stains fungal structures; mounts hyphae and spores.

Wet mount preparation is used for:
a) Motility and morphology of protozoa ✅
b) Gram stain
c) ELISA
d) PCR

Explanation: Fresh specimen observed for motile trophozoites or bacteria.

Hemocytometer is used for:
a) Cell counting (RBC, WBC, platelets) ✅
b) PCR
c) Culture
d) ELISA

Explanation: Counting grid under microscope; used for manual hematology counts.

Coagulometer measures:
a) PT, aPTT ✅
b) Blood glucose
c) Cholesterol
d) Enzyme activity

Explanation: Detects clot formation time; used in coagulation labs.

Automated hematology analyzers use:
a) Impedance, flow cytometry ✅
b) PCR
c) ELISA
d) Gram stain

Explanation: Counts and differentiates blood cells; high throughput and precision.

Spectrofluorometer principle:
a) Measures fluorescence emission ✅
b) Absorbance only
c) Centrifugation
d) ELISA only

Explanation: Excitation of fluorophores; emission measured; highly sensitive.

Osmometer measures:
a) Osmolality of plasma/urine ✅
b) pH
c) Glucose
d) Enzyme activity

Explanation: Freezing point depression or vapor pressure; critical for fluid balance studies.

Refractometer measures:
a) Total protein, specific gravity ✅
b) Enzyme activity
c) Blood gas
d) DNA concentration

Explanation: Measures refractive index; rapid bedside assessment.

Photometer vs spectrophotometer:
a) Photometer measures intensity of light; spectrophotometer measures wavelength-specific absorbance ✅
b) Both same
c) Photometer measures enzyme
d) Spectrophotometer measures pH

Explanation: Spectrophotometer allows wavelength selection; photometer is broadband.

ELISA plate read at:
a) 450 nm (commonly) ✅
b) 600 nm
c) 540 nm
d) 700 nm

Explanation: Depends on chromogen used; standard OD measured by microplate reader.

PCR amplification requires:
a) Template DNA, primers, dNTPs, Taq polymerase ✅
b) Only DNA
c) Only primers
d) Only dNTPs

Explanation: Enzyme and primers essential for exponential amplification of target DNA.

Agarose gel electrophoresis separates nucleic acids by:
a) Size ✅
b) Charge only
c) Shape
d) Mass

Explanation: Smaller fragments move faster; visualized with ethidium bromide/gel red.

SDS-PAGE separates proteins by:
a) Molecular weight ✅
b) Charge only
c) Shape
d) DNA content

Explanation: SDS denatures proteins; uniform negative charge; size-dependent migration.

Western blot detects:
a) Specific proteins ✅
b) DNA
c) RNA
d) Lipids

Explanation: Transfer to membrane; primary and secondary antibodies; enzyme or fluorescent detection.

Blood culture contamination reduced by:
a) Proper skin antisepsis ✅
b) Delayed incubation
c) Using water only
d) No precautions

Explanation: 70% alcohol + iodine reduces skin flora contamination.

Kirby-Bauer standardization includes:
a) 0.5 McFarland standard ✅
b) Any turbidity
c) No standard needed
d) Only visual estimation

Explanation: Ensures reproducible inoculum density for antibiotic susceptibility testing.

Anaerobic culture requires:
a) Anaerobic jar or chamber ✅
b) Chocolate agar only
c) Blood agar in air
d) MacConkey agar

Explanation: Oxygen-free environment; thioglycolate broth also used.

Viral culture requires:
a) Tissue/cell lines ✅
b) Agar plates
c) Blood only
d) Sabouraud agar

Explanation: Viruses replicate in living cells; cytopathic effect observed.

Mycology media includes:
a) Sabouraud dextrose agar, Brain heart infusion agar ✅
b) Blood agar only
c) MacConkey only
d) Chocolate agar

Explanation: Supports fungal growth; selective agents prevent bacterial contamination.

🧬 Histopathology & Cytopathology

The first step in histopathology is:
a) Fixation ✅
b) Embedding
c) Sectioning
d) Staining

Explanation: Fixation preserves tissue structure and prevents autolysis and decomposition; formalin is most commonly used.

The most common fixative in histopathology:
a) 10% Neutral Buffered Formalin ✅
b) Bouin’s solution
c) Alcohol
d) Acetone

Explanation: Preserves tissue morphology and proteins; widely used in routine pathology labs.

Paraffin embedding requires tissue dehydration using:
a) Alcohol series ✅
b) Water
c) PBS only
d) Formalin only

Explanation: Dehydration removes water; cleared with xylene or similar solvent before paraffin infiltration.

Microtome is used for:
a) Sectioning paraffin-embedded tissue ✅
b) Staining tissue
c) Fixation
d) Mounting slides

Explanation: Produces thin sections (3–5 µm) for microscopic examination.

Hematoxylin stains:
a) Nuclei blue/purple ✅
b) Cytoplasm pink
c) Collagen green
d) Lipids red

Explanation: Basic dye; binds to acidic nuclear components (DNA/RNA).

Eosin stains:
a) Cytoplasm, extracellular matrix pink ✅
b) Nuclei blue
c) Lipids green
d) Collagen red

Explanation: Acidic dye; binds to basic cytoplasmic proteins.

H&E stain is:
a) Hematoxylin & Eosin ✅
b) Hematoxylin & Alcian blue
c) Eosin & PAS
d) None

Explanation: Most commonly used stain in histopathology; differentiates nucleus and cytoplasm.

Periodic Acid-Schiff (PAS) stain highlights:
a) Carbohydrates, glycogen ✅
b) Lipids
c) Nucleic acids
d) Proteins

Explanation: Oxidation of carbohydrates → aldehyde formation; reacts with Schiff reagent → magenta color.

Masson’s trichrome stains:
a) Collagen blue/green, muscle red ✅
b) Nuclei only
c) Lipids
d) Carbohydrates

Explanation: Differentiates connective tissue (collagen) from muscle fibers; used in fibrosis detection.

Reticulin stain detects:
a) Reticular fibers (type III collagen) ✅
b) Nuclei
c) Lipids
d) Cytoplasm

Explanation: Silver impregnation method; black fibers visualized in liver, bone marrow, lymph nodes.

Acid-fast stain is used in histopathology for:
a) Mycobacteria ✅
b) Fungi
c) Viruses
d) Parasites

Explanation: Ziehl-Neelsen or Kinyoun methods; stains mycolic acid-rich cell walls red.

Oil Red O stains:
a) Lipids in frozen sections ✅
b) Proteins
c) Carbohydrates
d) Nucleic acids

Explanation: Fat-soluble dye; cannot be used on paraffin-embedded sections due to solvent removal of lipids.

Immunohistochemistry (IHC) detects:
a) Specific antigens in tissue using antibodies ✅
b) Lipids
c) Carbohydrates
d) DNA only

Explanation: Antibody-antigen binding visualized with chromogen; used in cancer diagnosis.

Common chromogen in IHC:
a) DAB (diaminobenzidine) ✅
b) Hematoxylin
c) Eosin
d) PAS

Explanation: DAB oxidized by peroxidase → brown precipitate at antigen site.

Cytology studies:
a) Cells only ✅
b) Tissues only
c) Organs
d) Enzymes

Explanation: Examines exfoliated or aspirated cells; less invasive than biopsy.

Pap smear is used for:
a) Cervical cancer screening ✅
b) Breast cancer
c) Liver disease
d) Thyroid disease

Explanation: Detects dysplastic or malignant cervical cells; Papanicolaou stain used.

Fine Needle Aspiration Cytology (FNAC) is used for:
a) Sampling cells from palpable masses ✅
b) Blood analysis
c) Tissue fixation
d) Urine analysis

Explanation: Minimally invasive; smears examined for morphology and diagnosis.

Papanicolaou stain highlights:
a) Nuclear detail and cytoplasm ✅
b) Lipids
c) Collagen
d) Carbohydrates

Explanation: Multi-chromatic stain; hematoxylin, orange G, EA dyes; nuclear detail critical for cytology.

Romanowsky stain is used for:
a) Blood and bone marrow smears ✅
b) Tissue paraffin sections
c) Lipid detection
d) Collagen fibers

Explanation: Wright, Giemsa, Leishman stains; stains nuclei purple, cytoplasm pink/blue.

Hematoxylin & Eosin in cytology:
a) Less commonly used than Pap ✅
b) Most common
c) Not used
d) Only for fungi

Explanation: Pap preferred for cervical cytology; H&E used in histology mainly.

Fixatives for cytology smears:
a) Alcohol, methanol ✅
b) Formalin only
c) Bouin’s only
d) Water

Explanation: Preserves cellular morphology; prevents drying artifact.

Liquid-based cytology advantages:
a) Reduces air-drying artifact, cleaner smear ✅
b) No advantages
c) More expensive only
d) Not widely used

Explanation: Cells suspended in preservative solution; better morphology and diagnosis.

Toluidine blue is used for:
a) Mast cells and acidic tissue components ✅
b) Lipids
c) Collagen
d) DNA only

Explanation: Metachromatic stain; mast cell granules appear purple/blue.

Alcian blue stains:
a) Acid mucopolysaccharides ✅
b) Lipids
c) Proteins
d) DNA

Explanation: Used for mucus-producing cells; pH-dependent staining.

Congo red stain detects:
a) Amyloid ✅
b) Lipids
c) Collagen
d) Proteins

Explanation: Amyloid deposits appear red under light; apple-green birefringence under polarized light.

Silver impregnation stains:
a) Reticulin fibers, fungi ✅
b) Collagen only
c) Cytoplasm
d) Nuclei

Explanation: Deposits silver on specific structures; enhances visualization.

Giemsa stain is used for:
a) Blood, bone marrow, and parasites ✅
b) Lipids
c) Fungi
d) Collagen

Explanation: Stains nucleic acids; identifies malaria, blood parasites, and chromatin in cells.

Ziehl-Neelsen stain in cytology:
a) Detects acid-fast bacilli in FNAC smears ✅
b) Only tissue
c) Only culture
d) Lipids

Explanation: Critical in tuberculosis diagnosis from lymph nodes or FNAC specimens.

Cytokeratin immunostaining identifies:
a) Epithelial origin tumors ✅
b) Mesenchymal
c) Neural
d) Lipid

Explanation: Intermediate filaments in epithelial cells; used in tumor typing.

Vimentin immunostaining identifies:
a) Mesenchymal cells ✅
b) Epithelial
c) Neural
d) Lipid

Explanation: Intermediate filaments in fibroblasts, endothelial cells; distinguishes sarcomas from carcinomas.

Ki-67 marker indicates:
a) Cell proliferation ✅
b) Apoptosis
c) Necrosis
d) Lipid

Explanation: Nuclear protein expressed in dividing cells; used in cancer grading.

TUNEL assay detects:
a) DNA fragmentation (apoptosis) ✅
b) Proliferation
c) Lipid deposition
d) Collagen

Explanation: Terminal deoxynucleotidyl transferase labels DNA breaks; apoptotic cells identified.

Flow cytometry in cytopathology detects:
a) Cell surface markers ✅
b) DNA only
c) Lipids
d) Collagen

Explanation: Uses fluorochrome-labeled antibodies; immunophenotyping of hematologic malignancies.

Frozen section is used for:
a) Rapid intraoperative diagnosis ✅
b) Routine paraffin section
c) Blood smears
d) Microbiology

Explanation: Tissue frozen, sectioned, stained; provides diagnosis during surgery.

Cryostat maintains tissue at:
a) −20°C to −30°C ✅
b) Room temp
c) 37°C
d) 4°C

Explanation: Rapid freezing preserves morphology for immediate sectioning.

Cytospin centrifuge is used for:
a) Concentrating cells on slide ✅
b) Tissue embedding
c) Sectioning
d) DNA extraction

Explanation: Spins low-volume fluids; deposits cells uniformly for staining.

Fine Needle Aspiration in thyroid:
a) Detects nodules, malignancy ✅
b) Measures hormones
c) Blood only
d) Lipids

Explanation: Smear examined for cellular morphology; minimally invasive diagnosis.

Mucicarmine stain detects:
a) Epithelial mucin ✅
b) Lipids
c) Collagen
d) Fungi

Explanation: Red staining of mucin in adenocarcinomas; helps in tumor typing.

Gomori methenamine silver (GMS) stain detects:
a) Fungi ✅
b) Collagen
c) Lipids
d) DNA

Explanation: Silver binds fungal cell wall; black structures against green background.

Periodic Acid-Schiff (PAS) in cytology detects:
a) Glycogen, fungi ✅
b) DNA
c) Lipids
d) Collagen

Explanation: Carbohydrate-rich structures stain magenta; useful in fungal detection.

Cytological sample from effusion is processed by:
a) Centrifugation, cytospin, staining ✅
b) Culture only
c) PCR only
d) Flow cytometry only

Explanation: Cells concentrated, fixed, stained for malignancy or infection.

Common Pap smear fixative:
a) 95% ethanol ✅
b) Formalin
c) Bouin’s
d) Methanol only

Explanation: Preserves nuclear morphology; prevents drying artifact.

Light green in Pap stain highlights:
a) Cytoplasm of metabolically active cells ✅
b) Nucleus
c) Lipids
d) Collagen

Explanation: EA component; gives green cytoplasm in superficial squamous cells.

Orange G in Pap stain stains:
a) Keratin ✅
b) Nucleus
c) Cytoplasm
d) Lipids

Explanation: Highlights keratinized cells; useful in detecting dysplasia.

Eosin azure (EA) in Pap stain stains:
a) Cytoplasm of squamous cells ✅
b) Nucleus
c) Keratin
d) Lipids

Explanation: EA mixture; differentiates intermediate, superficial cells in cervical smears.

Cytology fixatives must:
a) Preserve morphology without distortion ✅
b) Only dehydrate
c) Only stain
d) Only culture

Explanation: Essential for accurate diagnosis; ethanol is preferred.

Air-drying artifact in cytology causes:
a) Nuclear shrinkage, chromatin clumping ✅
b) Improved nuclear detail
c) No effect
d) Only cytoplasm changes

Explanation: Rapid fixation prevents artifact; delays or improper fixatives worsen quality.

Cervical dysplasia is graded using:
a) Bethesda system ✅
b) WHO only
c) TNM
d) AJCC

Explanation: Standardized reporting of Pap smear; LSIL, HSIL classification.

FNAC of lymph node shows Reed-Sternberg cells; likely diagnosis:
a) Hodgkin lymphoma ✅
b) Non-Hodgkin lymphoma
c) Reactive hyperplasia
d) Metastasis

Explanation: Large binucleated cells with prominent nucleoli; diagnostic for Hodgkin lymphoma.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

Cytology quality control includes:
a) Proper fixation, staining, labeling, and slide review ✅
b) Only staining
c) Only labeling
d) Only fixation

Explanation: Ensures reproducibility, accurate diagnosis, minimal errors.

Bouin’s solution is mainly used for:
a) Testes and soft tissues ✅
b) Bone
c) Lipid tissues
d) Blood smears

Explanation: Contains picric acid, formaldehyde, and acetic acid; excellent for preserving delicate structures like testes, embryos.

Zenker’s fixative is used for:
a) Bone marrow and delicate tissues ✅
b) Fat
c) Frozen sections
d) Blood

Explanation: Mercuric acid + potassium dichromate + acetic acid; preserves fine nuclear and cytoplasmic detail.

Formalin pigment forms in:
a) Acidic formalin solutions ✅
b) Neutral formalin
c) Bouin’s solution
d) Alcohol fixative

Explanation: Brown-black artifact; prevents by using neutral buffered formalin.

Decalcification is necessary for:
a) Bone tissue ✅
b) Liver
c) Spleen
d) Kidney

Explanation: Hard tissues need acid or EDTA decalcification for sectioning.

Microtome knife angle affects:
a) Section quality ✅
b) Fixation
c) Staining
d) Embedding

Explanation: Proper angle ensures smooth, even sections; prevents chatter and tearing.

Cryostat sections are typically:
a) 5–10 µm ✅
b) 20–50 µm
c) 1–2 mm
d) 50–100 µm

Explanation: Thin sections for rapid frozen diagnosis; allows high-resolution microscopy.

Artifacts in histopathology can be due to:
a) Fixation, dehydration, sectioning ✅
b) Only staining
c) Only mounting
d) Only embedding

Explanation: Proper technique reduces artifacts like shrinkage, folds, or bubbles.

Sudan III and Oil Red O are used for:
a) Lipid detection in frozen sections ✅
b) Carbohydrates
c) Proteins
d) Nucleic acids

Explanation: Lipid-soluble dyes; paraffin processing removes lipids, hence frozen sections are used.

Alcian Blue-PAS combined stain:
a) Differentiates acidic and neutral mucins ✅
b) Lipids
c) Collagen only
d) Nucleic acids

Explanation: Acid mucopolysaccharides stain blue; neutral mucins magenta; used in GI tract pathology.

Ziehl-Neelsen stain is acid-fast because:
a) Mycolic acid resists decolorization with acid alcohol ✅
b) Gram-positive bacteria resist
c) Lipids resist
d) Proteins resist

Explanation: Carbol fuchsin penetrates waxy cell wall; acid alcohol removes stain from non-acid-fast organisms.

Gram stain in tissue sections:
a) Identifies bacteria in situ ✅
b) Stains fungi
c) Stains viruses
d) Only culture

Explanation: Helps detect bacterial morphology directly in histological samples.

GMS stain in histology is used for:
a) Fungal hyphae ✅
b) Collagen fibers
c) Lipids
d) Nucleic acids

Explanation: Silver impregnation; fungi appear black on green background; sensitive for Pneumocystis, Candida.

Masson-Fontana stain detects:
a) Melanin ✅
b) Lipids
c) Glycogen
d) Collagen

Explanation: Silver reduction method; melanin appears black.

Prussian blue stain detects:
a) Iron (ferric) ✅
b) Calcium
c) Lipids
d) Glycogen

Explanation: Ferric ions react with potassium ferrocyanide → blue pigment; used in hemochromatosis diagnosis.

Von Kossa stain detects:
a) Calcium salts ✅
b) Iron
c) Collagen
d) Lipids

Explanation: Silver nitrate reacts with phosphate in calcium salts; black deposits visible; used in bone pathology.

Reticulin fibers in liver fibrosis are highlighted by:
a) Silver impregnation ✅
b) H&E
c) PAS
d) Sudan III

Explanation: Type III collagen; forms mesh-like network in fibrosis, cirrhosis.

Immunohistochemistry controls include:
a) Positive and negative controls ✅
b) Only positive
c) Only negative
d) None

Explanation: Ensures antibody specificity and staining accuracy; prevents false positives/negatives.

Frozen section advantage:
a) Rapid intraoperative diagnosis ✅
b) Permanent fixation
c) Higher resolution than paraffin
d) Better staining

Explanation: Quick results for surgical decisions; limited morphological detail compared to paraffin sections.

Cytology smear should be:
a) Thin, uniform, well-fixed ✅
b) Thick
c) Air-dried only
d) Overstained

Explanation: Ensures clear nuclear detail; prevents overlapping and artifacts.

Cytology Papanicolaou stain phases include:
a) Hematoxylin, OG-6, EA ✅
b) Only hematoxylin
c) Only eosin
d) Only methylene blue

Explanation: Multi-step; nuclear and cytoplasmic differentiation critical for cytopathology.

FNAC of lymph node with numerous plasma cells likely indicates:
a) Chronic inflammation ✅
b) Acute bacterial infection
c) Hodgkin lymphoma
d) Metastasis

Explanation: Plasma cells indicate humoral immune response; helps differentiate reactive vs malignant lesions.

Cytology fixative for Pap smear:
a) 95% ethanol ✅
b) Formalin
c) Bouin’s
d) Water

Explanation: Rapid penetration, preserves nuclear details; prevents drying artifact.

Common artifact in cytology smears:
a) Air-drying ✅
b) Overstaining
c) Understaining
d) Proper fixation

Explanation: Causes nuclear shrinkage and chromatin clumping; prevents accurate diagnosis.

Cytology of pleural effusion uses:
a) Centrifugation, cytospin, staining ✅
b) Culture only
c) Only Pap stain
d) Only H&E

Explanation: Concentrates cells; helps detect malignancy, infection.

Cytology of thyroid nodules differentiates:
a) Benign vs malignant lesions ✅
b) Only hyperthyroid
c) Only goiter
d) Only cysts

Explanation: FNAC allows morphologic evaluation; Bethesda system standardizes reporting.

Liquid-based cytology advantage:
a) Cleaner, uniform cell distribution ✅
b) More artifacts
c) Less sensitive
d) Expensive only

Explanation: Reduces air-drying artifact; improves detection of abnormal cells.

Immunocytochemistry detects:
a) Specific antigens in cells ✅
b) Lipids
c) Carbohydrates
d) Nucleic acids

Explanation: Uses labeled antibodies; enhances diagnostic accuracy in FNAC and effusions.

TUNEL assay in cytology detects:
a) Apoptotic cells ✅
b) Proliferating cells
c) Necrotic cells
d) Lipid accumulation

Explanation: DNA fragmentation labeled with terminal transferase; identifies programmed cell death.

Cytology of CSF helps in:
a) Detecting meningitis, malignancy ✅
b) Blood typing
c) Biochemistry only
d) PCR only

Explanation: Cellular morphology examination; complements microbiology and biochemistry.

Immunocytochemistry marker CK7 is positive in:
a) Epithelial cells (lung, breast) ✅
b) Mesenchymal
c) Neural
d) Lymphoid

Explanation: Cytokeratin 7 expression helps identify carcinoma origin.

CK20 marker is positive in:
a) Colon carcinoma ✅
b) Lung carcinoma
c) Breast carcinoma
d) Sarcoma

Explanation: Helps differentiate metastatic carcinoma sites.

Cytology of urine can detect:
a) Malignant cells ✅
b) RBC count only
c) Proteins only
d) Glucose only

Explanation: Urine cytology identifies urothelial carcinoma and dysplastic cells.

Cytology of sputum detects:
a) Lung carcinoma ✅
b) Liver disease
c) Kidney disease
d) Heart disease

Explanation: Exfoliated bronchial cells examined; Pap or Papanicolaou staining.

Cytology of bronchial brushings:
a) Diagnoses lung carcinoma ✅
b) Only infections
c) Only fibrosis
d) Only COPD

Explanation: Direct collection of epithelial cells from bronchi; enhances cytologic yield.

Cytology of serous effusions includes:
a) Cell concentration, staining, microscopic evaluation ✅
b) Only biochemistry
c) Only culture
d) Only Gram stain

Explanation: Distinguishes reactive vs malignant effusions.

Cytology of cerebrospinal fluid (CSF) should be processed within:
a) 1–2 hours ✅
b) 24 hours
c) 48 hours
d) 1 week

Explanation: Prevents cell degeneration; preserves morphology.

Immunocytochemistry marker CD20 is for:
a) B lymphocytes ✅
b) T lymphocytes
c) Epithelial
d) Mesenchymal

Explanation: B-cell lineage identification in lymphoma or leukemia cytology.

Immunocytochemistry marker CD3 is for:
a) T lymphocytes ✅
b) B lymphocytes
c) Epithelial cells
d) Mesenchymal cells

Explanation: Helps classify hematolymphoid neoplasms.

Cytology of FNAC in breast lump shows ductal carcinoma; marker likely positive:
a) CK7 ✅
b) CK20
c) CD20
d) Vimentin

Explanation: CK7 positive in breast ductal carcinoma; helps confirm epithelial origin.

Cytology of malignant effusion shows:
a) Cell clusters, nuclear atypia ✅
b) Only RBC
c) Only WBC
d) Only bacteria

Explanation: Morphological features like high N:C ratio, pleomorphism indicate malignancy.

Silver impregnation in cytology highlights:
a) Fungi and reticulin fibers ✅
b) Lipids
c) Collagen
d) Nucleic acids

Explanation: Used for delicate structures; sensitive method for diagnostic purposes.

Cytology fixative for immunocytochemistry:
a) Alcohol-based or acetone ✅
b) Formalin only
c) Bouin’s
d) Water

Explanation: Preserves antigenicity; formalin may mask epitopes.

Cytology quality control includes:
a) Proper fixation, staining, labeling, slide review ✅
b) Only staining
c) Only labeling
d) Only fixation

Explanation: Ensures reproducible and accurate diagnostic results.

FNAC sample adequacy is assessed by:
a) Cellularity, representative tissue, proper smear ✅
b) Only volume
c) Only color
d) Only thickness

Explanation: Adequate cellularity ensures reliable diagnosis; insufficient material may require repeat aspiration.

Cytology of lymph node showing centroblasts and centrocytes indicates:
a) Follicular lymphoma ✅
b) Hodgkin lymphoma
c) Reactive hyperplasia
d) Metastasis

Explanation: Characteristic cell types in follicular lymphoma; morphology guides diagnosis.

Cytology of renal aspirate shows crescentic glomerulonephritis; stained with:
a) H&E ✅
b) PAS only
c) Masson trichrome only
d) Silver only

Explanation: H&E shows cellular crescents; PAS or silver may complement but H&E primary stain.

Cytology of malignant pleural effusion stained by:
a) Pap stain ✅
b) H&E only
c) Giemsa only
d) Oil Red O

Explanation: Pap provides nuclear and cytoplasmic detail; standard for effusions.

FNAC of thyroid showing colloid indicates:
a) Benign goiter ✅
b) Papillary carcinoma
c) Follicular carcinoma
d) Medullary carcinoma

Explanation: Abundant colloid and uniform follicular cells indicate benign lesion.

Cytology smear should avoid:
a) Thick smears ✅
b) Thin smears
c) Proper fixation
d) Uniform distribution

Explanation: Thick smears obscure nuclear details; thin uniform smears provide clarity.

Cytology evaluation includes:
a) Cell morphology, architecture, background ✅
b) Only background
c) Only color
d) Only size

Explanation: Comprehensive assessment ensures correct diagnosis; considers all cellular features.

Tissue fixation aims to:
a) Preserve morphology and prevent autolysis ✅
b) Only stain the tissue
c) Only dehydrate
d) Only embed tissue

Explanation: Fixation stabilizes proteins and cellular structures, preventing decay and artifact formation.

Common fixative for electron microscopy:
a) Glutaraldehyde ✅
b) Formalin
c) Alcohol
d) Bouin’s

Explanation: Glutaraldehyde preserves ultrastructure by crosslinking proteins; essential for EM.

Artifacts in histopathology may result from:
a) Improper fixation, dehydration, or sectioning ✅
b) Correct staining
c) Adequate embedding
d) Proper mounting

Explanation: Artifacts distort morphology; proper technique minimizes errors.

Frozen sections are limited by:
a) Reduced detail compared to paraffin sections ✅
b) Time consumption
c) Cost only
d) No staining ability

Explanation: Rapid diagnosis but morphological resolution is lower than paraffin-embedded sections.

Bouin’s solution contains:
a) Picric acid, formaldehyde, acetic acid ✅
b) Formalin only
c) Alcohol only
d) Glutaraldehyde only

Explanation: Excellent for delicate structures; yellow pigment removed with alcohol washes.

Zenker’s fixative contains:
a) Mercuric chloride, potassium dichromate, acetic acid ✅
b) Formalin only
c) Alcohol only
d) Bouin’s components

Explanation: Preserves nuclei and cytoplasm; used for hematopoietic tissue and endocrine glands.

Decalcification in bone biopsy uses:
a) Acid or EDTA ✅
b) Alcohol
c) Formalin
d) Bouin’s

Explanation: Hard tissue must be softened for microtomy; EDTA chelates calcium without damaging tissue.

H&E staining colors nuclei and cytoplasm:
a) Nuclei blue/purple, cytoplasm pink ✅
b) Nuclei pink, cytoplasm blue
c) Both blue
d) Both pink

Explanation: Hematoxylin binds acidic nuclear components; eosin binds basic cytoplasmic proteins.

PAS stain highlights:
a) Glycogen, mucopolysaccharides ✅
b) Lipids
c) Proteins
d) Collagen

Explanation: Periodic acid oxidizes sugars to aldehydes; Schiff reagent gives magenta color.

Masson’s trichrome highlights:
a) Collagen blue/green, muscle red ✅
b) Lipids
c) Nucleic acids
d) Fungi

Explanation: Differentiates connective tissue from muscle fibers; used in fibrosis evaluation.

Reticulin fibers are:
a) Type III collagen ✅
b) Type I collagen
c) Elastin
d) Keratin

Explanation: Visualized with silver impregnation; forms supportive mesh in liver, bone marrow, lymph nodes.

Silver impregnation stains are used for:
a) Fungi and reticulin fibers ✅
b) Collagen only
c) Lipids
d) Carbohydrates

Explanation: Silver binds delicate structures; widely used in histology and cytology.

Immunohistochemistry (IHC) detects:
a) Specific antigens using labeled antibodies ✅
b) Lipids
c) Collagen
d) DNA only

Explanation: Enables tumor typing, pathogen detection, and biomarker identification.

Common chromogen in IHC:
a) DAB (diaminobenzidine) ✅
b) Hematoxylin
c) Eosin
d) Alcian blue

Explanation: Produces brown precipitate at antigen site; widely used in diagnostic pathology.

Cytology primarily examines:
a) Individual cells ✅
b) Whole tissue
c) Organs
d) Proteins

Explanation: Smears or aspirates; minimally invasive compared to biopsy.

Pap smear detects:
a) Cervical epithelial abnormalities ✅
b) Breast cancer
c) Thyroid nodules
d) Kidney disease

Explanation: Early detection of pre-malignant or malignant changes; stained with Papanicolaou method.

Fine Needle Aspiration Cytology (FNAC) is:
a) Minimally invasive cell sampling ✅
b) Tissue sectioning
c) Blood culture
d) Only staining

Explanation: Used for thyroid, lymph node, breast, and soft tissue lesions; cytology provides diagnosis without surgery.

Pap stain components include:
a) Hematoxylin, Orange G, EA ✅
b) Only hematoxylin
c) Only eosin
d) Only methylene blue

Explanation: Multichromatic staining differentiates nucleus and cytoplasm; identifies dysplastic cells.

Romanowsky stains (Giemsa, Wright) are used for:
a) Blood, bone marrow, parasites ✅
b) Paraffin tissue
c) Lipid staining
d) Collagen

Explanation: Stains nucleic acids; commonly used in hematology cytology.

Acid-fast stain detects:
a) Mycobacteria ✅
b) Fungi only
c) Lipids
d) Collagen

Explanation: Ziehl-Neelsen method; waxy cell wall resists decolorization with acid alcohol.

Oil Red O and Sudan III stains:
a) Lipids in frozen tissue ✅
b) Proteins
c) Carbohydrates
d) Nucleic acids

Explanation: Lipid-soluble dyes; paraffin processing removes lipids, so frozen sections are required.

Toluidine blue stains:
a) Mast cells metachromatically ✅
b) Lipids
c) Collagen
d) Glycogen

Explanation: Mast cell granules appear purple; cytoplasm blue.

Alcian blue stains:
a) Acid mucopolysaccharides ✅
b) Collagen
c) Lipids
d) DNA

Explanation: pH-dependent staining; used in GI tract and mucinous tumors.

Congo red stains:
a) Amyloid deposits ✅
b) Lipids
c) Collagen
d) Proteins

Explanation: Red under light; apple-green birefringence under polarized light.

Mucicarmine stains:
a) Epithelial mucin red ✅
b) Collagen
c) Lipids
d) Fungi

Explanation: Highlights mucin in adenocarcinomas.

Immunocytochemistry detects:
a) Antigens in cells ✅
b) Lipids
c) Carbohydrates
d) Proteins only

Explanation: Uses antibodies on smears or cytospin samples; aids in tumor typing.

TUNEL assay detects:
a) DNA fragmentation (apoptosis) ✅
b) Cell proliferation
c) Necrosis
d) Lipid deposits

Explanation: Labels fragmented DNA ends; used in research and diagnostic cytology.

Flow cytometry in cytology:
a) Detects cell surface markers ✅
b) Only nucleic acids
c) Only proteins
d) Only lipids

Explanation: Immunophenotyping of hematologic malignancies; uses fluorescent-labeled antibodies.

FNAC of lymph node showing Reed-Sternberg cells:
a) Hodgkin lymphoma ✅
b) Non-Hodgkin lymphoma
c) Reactive hyperplasia
d) Metastasis

Explanation: Characteristic binucleated cells with prominent nucleoli.

Cytology of CSF:
a) Detects infection or malignancy ✅
b) Only RBC
c) Only protein
d) Only glucose

Explanation: Rapid assessment for meningitis, leukemia, or metastatic disease.

CK7 positive tumors include:
a) Breast, lung ✅
b) Colon
c) Sarcoma
d) Lymphoma

Explanation: Helps differentiate epithelial tumor origins.

CK20 positive tumors include:
a) Colon carcinoma ✅
b) Lung carcinoma
c) Breast carcinoma
d) Sarcoma

Explanation: Useful for metastatic carcinoma diagnosis.

CD20 is a marker for:
a) B lymphocytes ✅
b) T lymphocytes
c) Epithelial cells
d) Mesenchymal cells

Explanation: Immunophenotyping B-cell malignancies.

CD3 is a marker for:
a) T lymphocytes ✅
b) B lymphocytes
c) Epithelial cells
d) Mesenchymal cells

Explanation: Identifies T-cell lineage in cytology or flow cytometry.

Cytology of effusions requires:
a) Cell concentration, staining, microscopic evaluation ✅
b) Only culture
c) Only Pap stain
d) Only H&E

Explanation: Differentiates reactive from malignant effusions.

Cytology of thyroid FNAC with colloid:
a) Benign goiter ✅
b) Papillary carcinoma
c) Follicular carcinoma
d) Medullary carcinoma

Explanation: Abundant colloid and uniform follicular cells indicate benign lesion.

Liquid-based cytology advantage:
a) Uniform cell distribution, cleaner smears ✅
b) More artifact
c) Less sensitive
d) Expensive only

Explanation: Improves diagnostic accuracy; reduces drying artifact.

Cytology smear evaluation includes:
a) Cell morphology, architecture, background ✅
b) Only background
c) Only size
d) Only color

Explanation: Comprehensive evaluation ensures accurate diagnosis.

Cytology quality control includes:
a) Proper fixation, staining, labeling, slide review ✅
b) Only staining
c) Only labeling
d) Only fixation

Explanation: Ensures reproducibility, prevents diagnostic errors.

Air-drying artifact in cytology causes:
a) Nuclear shrinkage, chromatin clumping ✅
b) Improved nuclear detail
c) No effect
d) Only cytoplasmic changes

Explanation: Rapid fixation prevents artifact; essential for accurate diagnosis.

FNAC of lymph node showing plasma cells:
a) Chronic inflammation ✅
b) Acute bacterial infection
c) Hodgkin lymphoma
d) Metastasis

Explanation: Plasma cells indicate humoral immune response.

FNAC of lymph node showing centroblasts and centrocytes:
a) Follicular lymphoma ✅
b) Hodgkin lymphoma
c) Reactive hyperplasia
d) Metastasis

Explanation: Characteristic cell types aid in lymphoma classification.

Immunohistochemistry positive control ensures:
a) Antibody works properly ✅
b) Staining fails
c) Only negative
d) Not important

Explanation: Confirms correct antigen detection; prevents false negatives.

Immunohistochemistry negative control ensures:
a) Specificity, absence of background staining ✅
b) Positive staining
c) Artifact
d) Not required

Explanation: Confirms that staining is antigen-specific; prevents false positives.

Cryostat sectioning temperature:
a) −20°C to −30°C ✅
b) Room temp
c) 4°C
d) 37°C

Explanation: Maintains tissue frozen for rapid sectioning and diagnosis.

Cytology of sputum detects:
a) Lung carcinoma ✅
b) Liver disease
c) Kidney disease
d) Heart disease

Explanation: Exfoliated bronchial cells evaluated; Pap stain commonly used.

Cytology of urine detects:
a) Malignant cells ✅
b) RBC only
c) Proteins only
d) Glucose only

Explanation: Early detection of urothelial carcinoma.

Cytospin centrifuge is used for:
a) Concentrating cells on slides ✅
b) Tissue embedding
c) Sectioning
d) DNA extraction

Explanation: Spreads low-volume samples uniformly for staining.

FNAC of breast shows ductal carcinoma; likely marker:
a) CK7 ✅
b) CK20
c) CD20
d) Vimentin

Explanation: Confirms epithelial origin of carcinoma.

Cytology of effusions stained with Pap shows:
a) Nuclear detail, cytoplasmic features ✅
b) Only background
c) Only color
d) Only thickness

Explanation: Proper staining critical for detecting malignancy in body fluids.

📝 Test Your Knowledge with a Real MLT Mock Test
Try our MLT Online Mock Test with exam-style MCQs.
👉 Click here to start the Mock Test

🩸 Blood Bank & Immunohematology MCQs

ABO blood group is determined by:
a) Presence or absence of A and B antigens on RBCs ✅
b) Antibodies in plasma only
c) Rh antigen only
d) Platelet antigens

Explanation: RBC surface expresses A or B antigens; antibodies in plasma complement typing.

Universal donor for RBC transfusion:
a) O negative ✅
b) AB positive
c) A positive
d) B negative

Explanation: Lacks A, B, and Rh antigens; can be given to any recipient in emergencies.

Universal recipient for RBC transfusion:
a) AB positive ✅
b) O negative
c) A positive
d) B negative

Explanation: Has both A and B antigens and Rh D antigen; can receive any blood type.

Rh blood group is determined by:
a) D antigen on RBC surface ✅
b) A antigen
c) B antigen
d) H antigen

Explanation: Rh D positive individuals have D antigen; important in hemolytic disease of newborn.

Hemolytic disease of the newborn is caused by:
a) Rh incompatibility ✅
b) ABO incompatibility only
c) Platelet mismatch
d) Leukocyte antibodies

Explanation: Maternal anti-D antibodies attack fetal Rh-positive RBCs if mother is Rh-negative.

Forward grouping in ABO typing tests:
a) RBC antigens using known antisera ✅
b) Plasma antibodies using RBCs
c) Both antigen and antibody
d) None

Explanation: Detects presence of A and B antigens on patient RBCs.

Reverse grouping in ABO typing tests:
a) Plasma antibodies using known RBCs ✅
b) RBC antigens using antisera
c) Rh typing
d) Crossmatching

Explanation: Confirms ABO group by testing naturally occurring antibodies in plasma.

Direct Coombs test detects:
a) Antibodies bound to RBCs in vivo ✅
b) Free antibodies in plasma
c) RBC antigens only
d) Platelet antigens

Explanation: Detects immune-mediated hemolysis (e.g., HDN, autoimmune hemolytic anemia).

Indirect Coombs test detects:
a) Free antibodies in serum ✅
b) Bound antibodies on RBCs
c) RBC antigens only
d) Platelet antigens

Explanation: Used for prenatal antibody screening and crossmatching.

Crossmatching ensures:
a) Compatibility between donor RBCs and recipient serum ✅
b) ABO typing only
c) Rh typing only
d) Platelet count

Explanation: Prevents hemolytic transfusion reactions; major and minor crossmatches done.

Antibody screening in blood bank detects:
a) Unexpected antibodies in patient serum ✅
b) ABO antibodies only
c) Rh antibodies only
d) Platelet antibodies

Explanation: Prevents transfusion reactions; uses reagent RBC panels.

Weak D testing is required for:
a) Rh-negative individuals to prevent HDN ✅
b) ABO typing
c) Platelet transfusion
d) Hemoglobinopathy

Explanation: Weak D individuals may have partial D antigen; critical in pregnancy and transfusion.

Kell blood group antigen is important because:
a) Can cause severe hemolytic transfusion reactions and HDN ✅
b) Not clinically significant
c) Only in platelets
d) Only in WBCs

Explanation: Anti-K antibodies can cause immune hemolysis in newborns.

Bombay blood group (Oh) lacks:
a) H antigen ✅
b) A antigen
c) B antigen
d) Rh antigen

Explanation: Cannot receive O blood; extremely rare; compatible donors must be Oh phenotype.

Platelet transfusion is indicated when:
a) Platelet count <10,000/µL in non-bleeding patients ✅
b) Hemoglobin <7 g/dL
c) WBC <4,000/µL
d) INR elevated

Explanation: Prevents spontaneous bleeding; thresholds vary for bleeding risk.

Fresh frozen plasma (FFP) contains:
a) All clotting factors ✅
b) Only platelets
c) Only RBCs
d) Only plasma proteins

Explanation: Used in coagulopathy, liver disease, massive transfusion, and factor deficiencies.

Cryoprecipitate contains:
a) Factor VIII, fibrinogen, vWF ✅
b) All clotting factors
c) RBCs
d) Platelets

Explanation: Concentrated source of fibrinogen and factor VIII; used in hemophilia and hypofibrinogenemia.

Indications for RBC transfusion include:
a) Hemoglobin <7 g/dL in stable patients ✅
b) WBC <4,000/µL
c) Platelets <10,000/µL
d) INR elevated

Explanation: Corrects anemia; triggers may vary based on clinical context.

Storage lesion in RBCs refers to:
a) Biochemical and morphological changes during storage ✅
b) Infection risk only
c) RBC antigen change
d) Platelet loss

Explanation: Includes decreased ATP, 2,3-DPG, membrane rigidity; affects oxygen delivery.

Irradiated blood products are used to prevent:
a) Transfusion-associated graft-versus-host disease (TA-GVHD) ✅
b) Hemolysis
c) ABO incompatibility
d) WBC contamination

Explanation: Gamma irradiation inactivates lymphocytes; critical for immunocompromised patients.

Leukoreduction in blood products reduces:
a) Febrile non-hemolytic transfusion reactions ✅
b) RBC hemolysis
c) ABO incompatibility
d) Platelet count

Explanation: Removes WBCs; reduces alloimmunization and CMV transmission risk.

Direct antiglobulin test (DAT) positive indicates:
a) Autoimmune hemolysis or HDN ✅
b) No hemolysis
c) Only ABO mismatch
d) Only Rh typing

Explanation: Coombs reagent binds antibody-coated RBCs; detects immune-mediated destruction.

Indirect antiglobulin test (IAT) is used in:
a) Prenatal antibody screening ✅
b) Direct hemolysis
c) Platelet typing
d) WBC count

Explanation: Detects circulating antibodies in maternal serum; prevents HDN.

ABO discrepancies can result from:
a) Weak antigens, unexpected antibodies, technical errors ✅
b) Only typing error
c) Only Rh mismatch
d) Only contamination

Explanation: Requires repeat testing, additional antisera, and reverse grouping.

Major crossmatch involves:
a) Donor RBCs with recipient serum ✅
b) Donor serum with recipient RBCs
c) Donor plasma only
d) Recipient plasma only

Explanation: Ensures no hemolysis will occur during transfusion.

Minor crossmatch involves:
a) Donor serum with recipient RBCs ✅
b) Donor RBCs with recipient serum
c) Platelets only
d) WBCs only

Explanation: Rarely causes reactions; important in large volume transfusions.

Alloimmunization occurs due to:
a) Exposure to foreign RBC antigens ✅
b) ABO-compatible transfusion
c) Autoimmune reaction
d) Platelet transfusion only

Explanation: Can complicate future transfusions; common antigens include Rh, Kell, Duffy.

Indications for FFP transfusion include:
a) Coagulation factor deficiency with bleeding ✅
b) Thrombocytopenia only
c) Anemia only
d) Leukopenia only

Explanation: Replaces deficient clotting factors; not indicated for volume expansion.

Blood group antigens are:
a) Glycoproteins or glycolipids on RBC membrane ✅
b) Proteins only
c) Lipids only
d) Nucleic acids

Explanation: Molecular structure determines serologic reactions; used for typing.

Hemolytic transfusion reaction is due to:
a) ABO incompatibility ✅
b) Rh compatibility
c) Platelet transfusion
d) FFP only

Explanation: Acute or delayed; leads to hemolysis, fever, hypotension, renal failure.

DAT positive in autoimmune hemolytic anemia indicates:
a) IgG or complement coating RBCs ✅
b) No antibody
c) Only Rh antigen
d) Only ABO mismatch

Explanation: Confirms immune-mediated hemolysis.

Crossmatch-compatible units prevent:
a) Acute hemolytic transfusion reactions ✅
b) Platelet refractoriness
c) Febrile reactions
d) CMV infection

Explanation: Ensures patient safety; essential before transfusion.

Kell negative donor is preferred for:
a) Female of childbearing age ✅
b) Male only
c) Elderly only
d) All patients

Explanation: Prevents anti-K immunization; reduces risk of HDN.

Rh negative mothers receive anti-D immunoglobulin:
a) At 28 weeks gestation and postpartum ✅
b) Only at delivery
c) Only first trimester
d) Only second trimester

Explanation: Prevents sensitization and subsequent HDN in future pregnancies.

Antigen-antibody reactions in blood bank follow:
a) Law of mass action ✅
b) First-order kinetics only
c) Enzyme reaction only
d) None

Explanation: Antibody concentration and antigen availability determine reaction strength.

Monoclonal antibodies in blood typing are:
a) Homogeneous antibodies specific for single epitope ✅
b) Polyclonal
c) Non-specific
d) Only IgM

Explanation: Provide standardized, reproducible results; widely used in modern blood banking.

DAT uses:
a) Coombs reagent ✅
b) Hematoxylin
c) Eosin
d) Giemsa

Explanation: Anti-human globulin binds in vivo antibodies coating RBCs; agglutination indicates positivity.

IAT uses:
a) Coombs reagent to detect free antibodies in serum ✅
b) Stains RBCs
c) Only plasma
d) Only platelets

Explanation: Detects antibodies before transfusion or prenatal testing.

Antibody identification panel consists of:
a) Group O RBCs with known antigens ✅
b) Random RBCs
c) Only donor RBCs
d) Only plasma

Explanation: Helps identify specific clinically significant antibodies in patient serum.

ABO blood group antibodies are naturally occurring:
a) IgM ✅
b) IgG
c) IgA
d) IgE

Explanation: React at room temperature; cause immediate hemolysis if mismatched transfused.

Rh antibodies are usually:
a) IgG ✅
b) IgM
c) IgA
d) IgE

Explanation: React at 37°C; cross placenta causing HDN.

Hemolytic disease of newborn can be prevented by:
a) Anti-D prophylaxis ✅
b) Blood transfusion
c) Iron supplementation
d) Platelet transfusion

Explanation: Prevents maternal sensitization to fetal Rh antigens.

ABO antibodies react optimally at:
a) Room temperature ✅
b) 37°C
c) 4°C only
d) 56°C

Explanation: IgM class; can cause immediate hemolytic reactions.

Rh antibodies react optimally at:
a) 37°C ✅
b) Room temperature
c) 4°C
d) 56°C

Explanation: IgG class; clinically significant for HDN and transfusion reactions.

Blood group O has which antibodies:
a) Anti-A and Anti-B ✅
b) Anti-A only
c) Anti-B only
d) None

Explanation: Universal donor plasma contains both antibodies; incompatible for recipients with A, B, or AB blood.

Blood group AB has which antibodies:
a) None ✅
b) Anti-A
c) Anti-B
d) Anti-A and Anti-B

Explanation: Can receive any ABO group RBCs; plasma contains no naturally occurring ABO antibodies.

Crossmatch incompatibility can occur due to:
a) Alloantibodies against minor antigens ✅
b) Only ABO mismatch
c) Only Rh mismatch
d) Platelet antigens

Explanation: Screening for unexpected antibodies prevents delayed hemolytic reactions.

Coombs reagent contains:
a) Anti-human globulin ✅
b) Anti-RBC
c) Anti-platelet
d) Anti-serum

Explanation: Binds IgG or complement on RBCs to cause visible agglutination.

Platelet antigen incompatibility can cause:
a) Refractoriness to transfusion ✅
b) Hemophilia
c) RBC hemolysis
d) HDN only

Explanation: Antibodies against HPA antigens can prevent effective platelet transfusion.

Blood group typing is mandatory before:
a) Any RBC transfusion ✅
b) Platelet transfusion only
c) FFP only
d) Cryoprecipitate only

Explanation: Ensures compatibility; prevents acute hemolytic transfusion reactions.

Blood transfusion reactions are classified as:
a) Acute and delayed ✅
b) Only acute
c) Only delayed
d) Only hemolytic

Explanation: Acute (<24 hrs) includes hemolytic, febrile, allergic; delayed occurs days to weeks later due to alloimmunization.

Febrile non-hemolytic transfusion reaction is due to:
a) Recipient antibodies against donor WBCs ✅
b) ABO mismatch
c) Rh mismatch
d) Platelet antibodies

Explanation: Common; manifests as fever, chills without hemolysis; prevented by leukoreduced products.

Allergic transfusion reaction is due to:
a) Recipient IgE antibodies to donor plasma proteins ✅
b) ABO mismatch
c) Rh mismatch
d) Platelet antigens

Explanation: Causes urticaria, itching; severe cases can lead to anaphylaxis.

Acute hemolytic transfusion reaction is usually caused by:
a) ABO incompatibility ✅
b) Rh mismatch
c) Platelet transfusion
d) FFP only

Explanation: Can be life-threatening; rapid hemolysis, hemoglobinuria, hypotension.

Delayed hemolytic transfusion reaction is usually caused by:
a) Alloantibodies against minor RBC antigens ✅
b) ABO mismatch
c) Rh mismatch only
d) Platelet antibodies

Explanation: Occurs 3–14 days post-transfusion; mild hemolysis, often subclinical.

CMV-negative blood products are required for:
a) Immunocompromised patients ✅
b) All adults
c) Healthy adults
d) Only children

Explanation: Prevents CMV transmission; WBCs carry latent CMV.

Washed RBCs are indicated for:
a) Severe allergic reactions to plasma proteins ✅
b) Anemia only
c) Platelet transfusion
d) FFP transfusion

Explanation: Removes plasma; prevents recurrent allergic reactions in sensitive patients.

Autologous blood donation is:
a) Patient donates own blood before surgery ✅
b) Donor blood for anyone
c) Only platelet donation
d) Only plasma donation

Explanation: Reduces risk of transfusion reactions and infections; used in elective surgery.

Therapeutic phlebotomy is used in:
a) Polycythemia vera ✅
b) Anemia
c) Leukopenia
d) Thrombocytopenia

Explanation: Removes excess RBCs to prevent hyperviscosity complications.

Blood irradiator uses:
a) Gamma rays ✅
b) X-rays only
c) UV only
d) Microwaves

Explanation: Destroys donor lymphocytes to prevent TA-GVHD.

Pre-transfusion testing includes:
a) ABO & Rh typing, antibody screening, crossmatch ✅
b) Only CBC
c) Only coagulation
d) Only platelet count

Explanation: Ensures safety and compatibility; standard protocol in all transfusions.

Hemolytic disease of newborn is most severe in:
a) Second Rh-positive pregnancy in Rh-negative mother ✅
b) First pregnancy only
c) ABO incompatibility
d) Platelet incompatibility

Explanation: Sensitization occurs during first pregnancy; subsequent pregnancies risk severe hemolysis.

Antibody titer in pregnancy is monitored to:
a) Assess risk/severity of HDN ✅
b) Detect infection
c) Detect anemia
d) Monitor platelets

Explanation: High titer (>1:16) may require intervention like intrauterine transfusion.

Major blood bank tests before transfusion:
a) ABO & Rh typing, antibody screen, crossmatch ✅
b) Only ABO
c) Only Rh
d) Only hemoglobin

Explanation: Minimizes risk of transfusion reactions.

Platelet transfusion threshold for non-bleeding patient:
a) <10,000/µL ✅
b) <50,000/µL
c) <100,000/µL
d) <150,000/µL

Explanation: Prevents spontaneous bleeding; higher thresholds for surgery or active bleeding.

Cryoprecipitate dosage for hypofibrinogenemia:
a) 1 unit per 10 kg body weight ✅
b) 10 units per kg
c) 5 units per kg
d) 2 units per kg

Explanation: Raises fibrinogen by ~50 mg/dL; used in DIC, liver disease.

Blood storage temperature for RBCs:
a) 1–6°C ✅
b) Room temperature
c) −20°C
d) 37°C

Explanation: Preserves RBC viability for up to 42 days depending on additive solution.

Blood storage temperature for platelets:
a) 20–24°C with constant agitation ✅
b) 1–6°C
c) −20°C
d) 37°C

Explanation: Prevents platelet activation; shelf life 5 days.

Blood storage temperature for FFP:
a) −18°C or colder ✅
b) 1–6°C
c) Room temp
d) 20–24°C

Explanation: Preserves clotting factors; thawed FFP must be used within 24 hours.

Red cell alloimmunization risk is highest in:
a) Multitransfused patients ✅
b) First-time transfusion
c) Platelet transfusion
d) Cryoprecipitate transfusion

Explanation: Repeated exposure to foreign antigens induces antibody formation.

Blood group antigens are genetically determined by:
a) ABO, Rh, Kell, Duffy, Kidd genes ✅
b) Only ABO gene
c) Only Rh gene
d) Only platelet genes

Explanation: Each antigen encoded by specific gene; inheritance is Mendelian.

Antibody screen is negative; crossmatch is:
a) Compatible ✅
b) Incompatible
c) Not required
d) Positive only

Explanation: No clinically significant antibodies detected; transfusion is safe.

IgG antibodies in blood bank react best at:
a) 37°C ✅
b) Room temperature
c) 4°C
d) 56°C

Explanation: Clinically significant; can cause HDN or delayed hemolytic reactions.

IgM antibodies in blood bank react best at:
a) Room temperature ✅
b) 37°C
c) 4°C only
d) 56°C

Explanation: Typically naturally occurring ABO antibodies; cause immediate hemolytic reactions.

Minor crossmatch is rarely done because:
a) Donor plasma volume is low ✅
b) Donor RBCs incompatible
c) ABO incompatibility
d) Rh incompatibility

Explanation: Minimal clinical significance; major crossmatch is most important.

Hemolytic transfusion reaction can present with:
a) Fever, chills, back pain, hemoglobinuria ✅
b) Only itching
c) Only urticaria
d) Only hypotension

Explanation: Rapid intravascular hemolysis due to ABO incompatibility.

Leukocyte-reduced RBCs prevent:
a) Febrile reactions and CMV transmission ✅
b) ABO incompatibility
c) Platelet refractoriness
d) FFP reactions

Explanation: Removes >99% of WBCs; improves transfusion safety.

Blood irradiation dose for prevention of TA-GVHD:
a) 25 Gy ✅
b) 10 Gy
c) 50 Gy
d) 5 Gy

Explanation: Lethal to lymphocytes while preserving RBC and platelet function.

Blood component therapy principle:
a) Replace only deficient component ✅
b) Transfuse whole blood always
c) Replace all components
d) Only plasma transfusion

Explanation: Minimizes volume overload and unnecessary exposure; improves patient safety.

CMV seronegative blood is preferred for:
a) Neonates and immunocompromised ✅
b) Healthy adults
c) Platelet transfusion only
d) Liver transplant only

Explanation: Prevents transmission of CMV; leukoreduction reduces but does not eliminate risk.

Washed RBCs are preferred in:
a) IgA deficiency with anti-IgA antibodies ✅
b) ABO incompatibility
c) Rh incompatibility
d) Platelet transfusion

Explanation: Prevents severe allergic or anaphylactic reactions.

Alloantibody identification requires:
a) RBC panel with known antigens ✅
b) Patient RBCs only
c) Donor serum only
d) Plasma proteins only

Explanation: Detects antibodies against clinically significant RBC antigens; guides transfusion.

DAT is positive in:
a) Autoimmune hemolytic anemia ✅
b) Iron deficiency anemia
c) Thalassemia minor
d) Leukemia only

Explanation: Detects IgG/complement bound to RBCs in vivo.

IAT is used for:
a) Screening maternal serum for antibodies ✅
b) Detecting bound antibodies on RBCs
c) Platelet antibody detection only
d) Only ABO typing

Explanation: Prevents HDN and delayed transfusion reactions.

Red cell antibody panel consists of:
a) 8–16 group O RBCs with known antigens ✅
b) Patient RBCs only
c) Donor plasma only
d) Platelets only

Explanation: Helps identify specific alloantibodies.

Bombay blood group individuals can receive:
a) Only Oh phenotype blood ✅
b) O negative
c) AB positive
d) Any blood type

Explanation: Lack of H antigen prevents compatibility with regular O blood.

Major complications of blood transfusion include:
a) Hemolytic, allergic, febrile, TRALI ✅
b) Only anemia
c) Only infection
d) Only thrombosis

Explanation: TRALI – transfusion-related acute lung injury; important to recognize early.

Minor blood transfusion reactions include:
a) Mild allergic reactions ✅
b) Hemolytic reaction
c) TRALI
d) Delayed hemolysis

Explanation: Typically self-limiting; antihistamines may suffice.

TRALI is caused by:
a) Donor anti-leukocyte antibodies ✅
b) ABO incompatibility
c) Rh incompatibility
d) Platelet antigen

Explanation: Leads to non-cardiogenic pulmonary edema; serious but rare.

Transfusion thresholds for hemoglobin:
a) <7 g/dL in stable patients ✅
b) <10 g/dL
c) <12 g/dL
d) <5 g/dL

Explanation: Avoids unnecessary transfusions; varies with patient comorbidities.

Blood group AB plasma is:
a) Universal donor for plasma ✅
b) Universal RBC donor
c) Universal recipient for RBC
d) Only for AB patients

Explanation: Contains no anti-A or anti-B antibodies; can be given to any patient.

O negative RBCs are:
a) Universal donor for RBCs ✅
b) Universal plasma donor
c) Universal recipient
d) Only for O negative

Explanation: Lacks A, B, Rh antigens; safe for emergency transfusions.

Cryoprecipitate contains high:
a) Fibrinogen, factor VIII ✅
b) RBCs
c) Platelets
d) Plasma proteins only

Explanation: Used for hemophilia A and hypofibrinogenemia.

ABO incompatibility may cause:
a) Acute hemolytic transfusion reaction ✅
b) Delayed hemolysis only
c) Febrile reaction only
d) Platelet refractoriness only

Explanation: IgM antibodies cause immediate intravascular hemolysis.

Rh incompatibility may cause:
a) HDN in subsequent pregnancies ✅
b) Immediate hemolysis in first transfusion
c) Platelet refractoriness
d) Febrile reaction

Explanation: IgG antibodies cross placenta; serious in second Rh-positive fetus.

Anti-D prophylaxis dose in pregnancy:
a) 300 µg at 28 weeks and postpartum ✅
b) 100 µg only
c) 50 µg only
d) Not required

Explanation: Prevents maternal sensitization to fetal Rh-positive RBCs.

Leukocyte reduction is done to prevent:
a) Febrile reactions and CMV transmission ✅
b) ABO incompatibility
c) Platelet refractoriness
d) RBC destruction

Explanation: WBC removal improves safety, especially in immunocompromised patients.

Washed RBCs remove:
a) Plasma proteins ✅
b) RBC antigens
c) Platelets
d) WBCs only

Explanation: Prevents allergic reactions in IgA-deficient patients.

Pre-transfusion testing includes:
a) ABO/Rh typing, antibody screen, crossmatch ✅
b) Only CBC
c) Only coagulation
d) Only platelet count

Explanation: Ensures safe and compatible transfusion.

Indications for platelet transfusion include:
a) Platelet count <10,000/µL in stable patients ✅
b) Hemoglobin <7 g/dL
c) WBC <4,000/µL
d) INR >1.5

Explanation: Prevents spontaneous bleeding; thresholds vary by clinical scenario.

🧪 Quality Control MCQs in MLT

Quality control (QC) in laboratory refers to:
a) Procedures to ensure accuracy and precision of lab tests ✅
b) Only equipment maintenance
c) Only reagent preparation
d) Only sample collection

Explanation: QC ensures that lab results are reliable, reproducible, and clinically accurate.

Internal quality control (IQC) is:
a) Routine checks within the laboratory using control materials ✅
b) External audits
c) Regulatory inspections
d) Staff training

Explanation: Uses control samples daily to verify analyzer performance.

External quality assessment (EQA) or proficiency testing:
a) Compares lab performance with other labs ✅
b) Daily control checks
c) Instrument calibration
d) Sample storage

Explanation: Ensures accuracy and standardization across different laboratories.

Westgard rules are used in:
a) QC for detecting errors in analytical systems ✅
b) Sample collection
c) Patient preparation
d) Reagent preparation

Explanation: Statistical rules help detect systematic or random errors in lab assays.

Accuracy in QC means:
a) Closeness of test result to true value ✅
b) Repeatability of results
c) Equipment precision
d) Sample integrity

Explanation: Reflects correctness of measurement; essential for clinical reliability.

Precision in QC means:
a) Reproducibility of repeated measurements ✅
b) Closeness to true value
c) Sample quality
d) Instrument calibration

Explanation: Results are consistent under unchanged conditions; important for method validation.

Random error affects:
a) Precision ✅
b) Accuracy
c) Sample integrity
d) Reagent stability

Explanation: Unpredictable fluctuations; reduce by repeated measurements.

Systematic error affects:
a) Accuracy ✅
b) Precision
c) Random variation
d) Sample collection

Explanation: Bias in measurement; caused by calibration error, faulty reagents, or method flaw.

Levey-Jennings chart is used for:
a) Monitoring QC over time ✅
b) Sample identification
c) Equipment calibration
d) Patient reporting

Explanation: Plots control values; identifies trends or shifts in assay performance.

Control material in QC:
a) Known concentration sample to validate assay ✅
b) Patient sample
c) Random reagent
d) Unknown sample

Explanation: Ensures method accuracy and consistency; can be commercial or lab-prepared.

Calibration of laboratory instruments ensures:
a) Results correspond to true values ✅
b) Sample integrity
c) Reagent stability
d) Staff performance

Explanation: Adjusts instrument response to standard values; prevents systematic errors.

Delta check in QC is used to:
a) Compare current and previous patient results for plausibility ✅
b) Recalibrate instruments
c) Prepare controls
d) Store samples

Explanation: Detects sample misidentification, analytical errors, or unexpected clinical changes.

QC frequency depends on:
a) Test type, volume, analyzer stability ✅
b) Staff availability only
c) Sample number only
d) Reagent expiry only

Explanation: High-volume automated tests may require multiple QC runs per day.

Run-to-run QC ensures:
a) Continuity of reliable results between successive analyses ✅
b) Sample storage
c) Staff training
d) Reagent quality

Explanation: Detects sudden shifts or drifts in analyzer performance.

Reference range verification in QC:
a) Confirms lab-specific normal ranges ✅
b) Validates reagent lot only
c) Monitors staff
d) Checks equipment only

Explanation: Ensures results interpretation matches population-specific values.

Control limits in QC are typically set at:
a) ±2 SD for warning, ±3 SD for rejection ✅
b) ±1 SD only
c) ±4 SD only
d) ±5 SD only

Explanation: Standard statistical limits help detect unacceptable deviation from target values.

QC failures require:
a) Investigation before releasing patient results ✅
b) Ignoring
c) Only retesting next day
d) Only documenting

Explanation: Identifies source of error; patient results may be inaccurate if ignored.

Accuracy check involves:
a) Using reference standards or calibrators ✅
b) Random patient samples
c) Control charts only
d) Instrument cleaning

Explanation: Confirms method measures true concentration of analyte.

Precision check involves:
a) Repeated analysis of same control sample ✅
b) Patient samples only
c) Instrument calibration only
d) Reagent preparation only

Explanation: Determines reproducibility of the test method under identical conditions.

QC in hematology includes:
a) Hemoglobin, RBC, WBC, platelet counts ✅
b) Only hemoglobin
c) Only WBC
d) Only platelets

Explanation: Daily QC ensures CBC results are accurate and reliable for diagnosis.

QC in clinical chemistry includes:
a) Glucose, electrolytes, liver, kidney function tests ✅
b) Only glucose
c) Only liver tests
d) Only electrolytes

Explanation: Ensures accurate biochemical results; prevents misdiagnosis.

QC in microbiology includes:
a) Media sterility, culture performance, staining technique ✅
b) Only incubator cleaning
c) Only plate labeling
d) Only autoclaving

Explanation: Validates methods, reagents, and incubators; ensures reliable microbial results.

QC in immunology includes:
a) Control sera for ELISA, rapid tests, antibody screening ✅
b) Only patient serum
c) Only equipment calibration
d) Only pipette checks

Explanation: Detects kit errors, reagent degradation, and operator mistakes.

Documentation in QC is important for:
a) Traceability, accreditation, and error analysis ✅
b) Only inspection
c) Only lab audit
d) Only patient report

Explanation: Proper record-keeping is essential for regulatory compliance and quality assurance.

Types of QC materials:
a) Commercial, pooled, patient-based ✅
b) Only commercial
c) Only patient
d) Only pooled

Explanation: Different materials ensure method validation and accuracy in diverse situations.

Control sample should be treated like:
a) Patient sample ✅
b) Discarded sample
c) Only for calibration
d) Only for instrument testing

Explanation: Ensures consistency; prevents false assurance from improper handling.

Analytical sensitivity refers to:
a) Lowest detectable concentration of analyte ✅
b) Reproducibility
c) Accuracy
d) Sample volume

Explanation: Important in detecting low-level analytes in clinical samples.

Analytical specificity refers to:
a) Ability to measure intended analyte without interference ✅
b) Low concentration detection
c) Reproducibility
d) Instrument precision

Explanation: Prevents false positives due to cross-reactivity.

Pre-analytical QC includes:
a) Proper sample collection, labeling, storage ✅
b) Instrument calibration only
c) Control charts only
d) Reagent preparation only

Explanation: Prevents errors before analysis; often major source of lab errors.

Post-analytical QC includes:
a) Review of results, delta checks, report verification ✅
b) Sample collection
c) Reagent prep
d) Instrument maintenance

Explanation: Ensures that results are clinically valid before release.

Total quality management (TQM) in lab includes:
a) QC, QA, SOPs, staff training, audits ✅
b) Only QC
c) Only equipment maintenance
d) Only documentation

Explanation: Comprehensive approach to maintain high standards across all lab processes.

Six sigma in QC aims to:
a) Minimize defects/errors to <3.4 per million ✅
b) Maximize errors
c) Only documentation
d) Only equipment calibration

Explanation: Statistical approach to improve lab accuracy and reliability.

QC sample failure may indicate:
a) Reagent degradation, instrument malfunction, operator error ✅
b) Patient error
c) Only equipment
d) Only sample error

Explanation: All sources of error must be investigated; prevents release of false results.

Calibration verification is done:
a) After changing reagent lot or maintenance ✅
b) Daily
c) Weekly only
d) Never

Explanation: Ensures method remains accurate after changes.

Proficiency testing frequency is usually:
a) Monthly or quarterly ✅
b) Daily
c) Yearly only
d) Never

Explanation: External check on lab performance; part of accreditation requirements.

Control charts detect:
a) Shifts, trends, and random errors ✅
b) Only reagent issues
c) Only instrument errors
d) Only sample collection errors

Explanation: Visual tool for monitoring assay performance over time.

Accuracy vs Precision:
a) Accuracy – closeness to true value; Precision – reproducibility ✅
b) Accuracy – reproducibility; Precision – true value
c) Both same
d) Unrelated

Explanation: Important distinction for QC interpretation.

QC failure action includes:
a) Stop reporting patient results until problem resolved ✅
b) Ignore
c) Repeat only next day
d) Only document

Explanation: Prevents release of incorrect clinical results.

Laboratory accreditation standards include:
a) ISO 15189 ✅
b) Only QC
c) Only instrument maintenance
d) Only documentation

Explanation: Ensures lab competence and quality; internationally recognized standard.

Pre-analytical errors contribute to:
a) 60–70% of total lab errors ✅
b) 10%
c) 30%
d) 5%

Explanation: Common sources: sample mislabeling, hemolysis, wrong collection tubes.

Analytical errors contribute to:
a) 10–15% of lab errors ✅
b) 50%
c) 70%
d) 5%

Explanation: Usually due to instrument malfunction, reagent degradation, or method issues.

Post-analytical errors contribute to:
a) 20–30% of lab errors ✅
b) 50%
c) 5%
d) 10%

Explanation: Errors in reporting, transcription, or interpretation.

Standard operating procedures (SOPs) ensure:
a) Consistency and reliability of lab processes ✅
b) Only documentation
c) Only equipment maintenance
d) Only staff training

Explanation: Stepwise instructions reduce variability and errors.

QC in point-of-care testing (POCT) is:
a) Daily control with external checks ✅
b) Not required
c) Only calibration
d) Only documentation

Explanation: Maintains accuracy in decentralized testing locations.

Analytical measurement range (AMR) is:
a) Range over which method provides accurate results without dilution ✅
b) Only instrument limit
c) Only patient sample limit
d) Only reagent range

Explanation: Ensures results are valid across clinical concentration ranges.

Reportable range verification ensures:
a) Patient results fall within validated analytical limits ✅
b) Only QC
c) Only instrument calibration
d) Only staff training

Explanation: Prevents reporting inaccurate or out-of-range results.

QC in molecular diagnostics includes:
a) Positive and negative controls, contamination checks ✅
b) Only sample collection
c) Only reagent prep
d) Only equipment

Explanation: Ensures PCR or molecular assays are accurate and contamination-free.

Control sample deviation beyond ±3 SD indicates:
a) Reject run; investigate ✅
b) Accept run
c) Ignore
d) Only document

Explanation: Standard statistical rule; prevents reporting erroneous results.

Trend in control chart indicates:
a) Gradual systematic error developing ✅
b) Random error
c) No significance
d) Only reagent problem

Explanation: Allows proactive correction before QC fails.

Shift in control chart indicates:
a) Sudden systematic change in assay performance ✅
b) Random variation
c) No problem
d) Only calibration

Explanation: Immediate investigation required; could be reagent, instrument, or operator issue.

💧 Body Fluids MCQs for MLT Exam

Cerebrospinal fluid (CSF) is normally:
a) Clear, colorless ✅
b) Turbid
c) Yellowish
d) Red

Explanation: Normal CSF is clear and colorless; any turbidity may indicate infection, hemorrhage, or high protein.

CSF glucose is normally:
a) 2/3 of plasma glucose ✅
b) Equal to plasma glucose
c) Half of plasma glucose
d) Same as CSF protein

Explanation: Decreased CSF glucose suggests bacterial or fungal infection, or malignancy.

Normal CSF protein level is:
a) 15–45 mg/dL ✅
b) 50–100 mg/dL
c) 5–10 mg/dL
d) 100–150 mg/dL

Explanation: Increased protein indicates infection, hemorrhage, or inflammation.

CSF WBC count in adults:
a) 0–5/µL ✅
b) 10–20/µL
c) 5–10/µL
d) 20–50/µL

Explanation: Elevated WBCs indicate meningitis or inflammatory conditions.

Predominant CSF cells in bacterial meningitis:
a) Neutrophils ✅
b) Lymphocytes
c) Eosinophils
d) Monocytes

Explanation: Bacterial infections induce neutrophilic pleocytosis.

Predominant CSF cells in viral meningitis:
a) Lymphocytes ✅
b) Neutrophils
c) Eosinophils
d) Monocytes

Explanation: Viral infections usually cause lymphocytic pleocytosis.

CSF sample for biochemical analysis should be:
a) Collected in sterile tube without anticoagulant ✅
b) EDTA tube
c) Heparin tube
d) Citrate tube

Explanation: Prevents interference in glucose and protein measurements.

CSF cytology requires:
a) EDTA tube ✅
b) Sterile tube
c) Heparin tube
d) Citrate tube

Explanation: Preserves cells for accurate counting and morphology.

Xanthochromia in CSF indicates:
a) Subarachnoid hemorrhage ✅
b) Viral infection
c) Bacterial infection
d) Normal CSF

Explanation: Yellow discoloration due to hemoglobin breakdown products.

Normal opening pressure of CSF in adults:
a) 70–180 mm H₂O ✅
b) 50–100 mm H₂O
c) 200–300 mm H₂O
d) 10–50 mm H₂O

Explanation: Elevated pressure suggests intracranial hypertension or infection.

Synovial fluid is normally:
a) Clear, viscous ✅
b) Turbid
c) Red
d) Cloudy

Explanation: Viscosity is due to hyaluronic acid; clarity indicates absence of inflammation.

Synovial fluid WBC count in normal joint:
a) <200/µL ✅
b) 500–1000/µL
c) 2000–5000/µL
d) >10,000/µL

Explanation: Elevated WBC indicates inflammatory or septic arthritis.

Normal synovial fluid protein:
a) <3 g/dL ✅
b) 4–6 g/dL
c) >6 g/dL
d) <1 g/dL

Explanation: Increased protein may indicate inflammation or infection.

Normal synovial fluid glucose:
a) Equal to plasma glucose ✅
b) Half of plasma
c) 2/3 of plasma
d) 0

Explanation: Low glucose suggests bacterial infection or rheumatoid arthritis.

Synovial fluid in septic arthritis is:
a) Turbid, WBC >50,000/µL, predominantly neutrophils ✅
b) Clear, low WBC
c) Yellow, lymphocytes
d) Red, eosinophils

Explanation: Acute bacterial infection; urgent diagnosis and treatment needed.

Normal pleural fluid is:
a) Clear, straw-colored, low protein ✅
b) Turbid, high protein
c) Red, high WBC
d) Cloudy, low glucose

Explanation: Transudate vs exudate differentiation is key in pleural effusions.

Light’s criteria differentiate:
a) Transudate vs exudate ✅
b) Normal vs abnormal CSF
c) Normal vs abnormal synovial fluid
d) None

Explanation: Exudate: pleural fluid protein/serum protein >0.5, LDH >0.6.

Normal pleural fluid glucose:
a) ~60 mg/dL or equal to plasma ✅
b) 10 mg/dL
c) 100 mg/dL
d) 200 mg/dL

Explanation: Low glucose suggests infection, malignancy, or rheumatoid effusion.

Normal pleural fluid WBC:
a) <1000/µL ✅
b) >5000/µL
c) 2000–5000/µL
d) >10,000/µL

Explanation: Elevated WBC indicates infection, malignancy, or inflammation.

Peritoneal fluid normal is:
a) Clear, straw-colored, WBC <500/µL ✅
b) Turbid, WBC >1000/µL
c) Red, WBC >5000/µL
d) Cloudy, WBC 1000–2000

Explanation: Ascitic fluid analysis helps differentiate transudate from exudate.

Serum-ascites albumin gradient (SAAG) >1.1 g/dL indicates:
a) Portal hypertension (transudate) ✅
b) Infection
c) Malignancy
d) Rheumatologic disease

Explanation: High gradient reflects hydrostatic pressure-related ascites.

Pericardial fluid normally is:
a) Clear, straw-colored, WBC <500/µL ✅
b) Turbid
c) Red
d) Cloudy

Explanation: Increased WBC or protein suggests pericarditis or infection.

Body fluid cytology is used for:
a) Detecting malignancy or abnormal cells ✅
b) Measuring glucose
c) Measuring protein
d) Checking viscosity

Explanation: Important in CSF, pleural, peritoneal, and synovial fluids for diagnostic purposes.

Eosinophilic pleural effusion suggests:
a) Parasitic infection, drug reaction, air in pleura ✅
b) Bacterial infection
c) Viral infection
d) Hemorrhage only

Explanation: Presence of eosinophils in fluid points to allergic, parasitic, or post-trauma causes.

Turbidity in CSF indicates:
a) Elevated WBC, infection ✅
b) Normal CSF
c) Only high protein
d) Only high glucose

Explanation: Turbidity correlates with pleocytosis; helps rapid clinical suspicion.

Xanthochromia in CSF persists for:
a) 1–2 weeks after hemorrhage ✅
b) 1–2 days
c) 1 month
d) 6 months

Explanation: Helps distinguish traumatic tap vs subarachnoid hemorrhage.

Traumatic tap in CSF shows:
a) Decreasing RBC count in successive tubes ✅
b) Uniform RBC count
c) Xanthochromia
d) Only WBC

Explanation: Differentiates accidental blood from true hemorrhage.

Chylous pleural effusion appears:
a) Milky, high triglycerides ✅
b) Clear
c) Straw-colored
d) Red

Explanation: Caused by lymphatic obstruction or trauma.

Pleural fluid neutrophilia indicates:
a) Acute bacterial infection ✅
b) Chronic disease
c) Malignancy
d) Viral infection

Explanation: Rapid influx of neutrophils; guides early treatment.

Pleural fluid lymphocytosis indicates:
a) TB, viral infection, malignancy ✅
b) Acute bacterial infection
c) Trauma
d) Fungal infection only

Explanation: Chronic inflammatory conditions show lymphocyte predominance.

Normal amniotic fluid:
a) Clear or pale yellow ✅
b) Green
c) Red
d) Turbid

Explanation: Abnormal color suggests meconium, blood, or infection.

Body fluid protein measurement differentiates:
a) Transudate vs exudate ✅
b) Bacterial vs viral
c) RBC vs WBC
d) Glucose levels

Explanation: High protein suggests exudate; low protein suggests transudate.

Lactate in CSF helps in:
a) Distinguishing bacterial vs viral meningitis ✅
b) Detecting hemorrhage
c) Protein estimation
d) Glucose estimation

Explanation: High CSF lactate suggests bacterial infection.

LDH in body fluids indicates:
a) Tissue damage or inflammation ✅
b) Only infection
c) Only malignancy
d) Only trauma

Explanation: Elevated LDH differentiates exudate from transudate in pleural and peritoneal fluids.

Cytospin technique is used for:
a) Concentrating cells in low-cell fluids ✅
b) Measuring protein
c) Measuring glucose
d) Only CSF collection

Explanation: Increases sensitivity for detecting abnormal cells.

Normal peritoneal fluid WBC:
a) <500/µL ✅
b) 1000–2000
c) >5000
d) >10,000

Explanation: Helps distinguish ascitic fluid types.

Normal peritoneal fluid glucose:
a) Equal to plasma glucose ✅
b) <20 mg/dL
c) >200 mg/dL
d) 50–60 mg/dL

Explanation: Low glucose suggests infection or malignancy.

Hemorrhagic CSF may be due to:
a) Traumatic tap or subarachnoid hemorrhage ✅
b) Viral infection
c) Bacterial infection
d) Normal variant

Explanation: Requires differentiation via xanthochromia and tube analysis.

Body fluid differential count includes:
a) Neutrophils, lymphocytes, eosinophils, monocytes ✅
b) RBCs only
c) Platelets only
d) Protein only

Explanation: Helps identify infection type and inflammatory status.

Pleural fluid amylase elevation indicates:
a) Pancreatic disease or esophageal rupture ✅
b) Infection only
c) Malignancy only
d) Trauma only

Explanation: Useful in differential diagnosis of effusions.

Normal synovial fluid viscosity:
a) High, string >4 cm ✅
b) Low
c) Milky
d) None

Explanation: Low viscosity indicates inflammatory arthritis.

Body fluid cytology is most sensitive in:
a) Malignancy detection ✅
b) Infection detection only
c) Glucose estimation
d) Protein estimation

Explanation: Detects abnormal cells even in low-cell fluids.

CSF lactate >35 mg/dL suggests:
a) Bacterial meningitis ✅
b) Viral meningitis
c) Normal
d) Hemorrhage

Explanation: High lactate indicates anaerobic metabolism by bacteria.

Pleural fluid ADA >40 U/L suggests:
a) Tuberculosis ✅
b) Bacterial infection
c) Viral infection
d) Malignancy

Explanation: ADA is enzyme marker for T-cell activity; high in TB effusion.

Normal CSF chloride:
a) 110–125 mEq/L ✅
b) 100–110
c) 130–140
d) 80–90

Explanation: Decreased in bacterial meningitis; stable in viral infections.

CSF cytology is performed to detect:
a) Malignant cells, infections ✅
b) Only protein
c) Only glucose
d) Only chloride

Explanation: Key diagnostic tool for CNS malignancies and infections.

Turbid pleural fluid indicates:
a) High WBC or chylous fluid ✅
b) Normal fluid
c) Low protein
d) Only blood

Explanation: Helps categorize effusions.

Body fluid pH measurement helps in:
a) Distinguishing transudate vs exudate ✅
b) Only infection
c) Only protein
d) Only glucose

Explanation: Low pH indicates empyema or infection; normal in transudates.

Red-tinged synovial fluid indicates:
a) Trauma or hemorrhage ✅
b) Infection only
c) Crystal arthritis
d) Normal

Explanation: Helps differentiate hemarthrosis from inflammatory causes.

Normal pericardial fluid protein:
a) <3 g/dL ✅
b) >5 g/dL
c) <1 g/dL
d) 4–6 g/dL

Explanation: Exudative pericardial effusions have higher protein due to infection or malignancy.

☣️ Toxicology & Advances in MLT

Toxicology is the study of:
a) Harmful effects of chemicals and drugs on living organisms ✅
b) Blood cells only
c) Microorganisms
d) Laboratory equipment

Explanation: Toxicology focuses on detecting, preventing, and managing poisoning from chemicals, drugs, and environmental toxins.

The most common route of poisoning is:
a) Oral ✅
b) Inhalation
c) Skin absorption
d) Injection

Explanation: Accidental or intentional ingestion is the most frequent route for toxic substances.

Acetaminophen toxicity primarily affects:
a) Liver ✅
b) Kidney
c) Brain
d) Heart

Explanation: Overdose leads to hepatocellular injury via toxic metabolite NAPQI.

Blood lead levels are measured in:
a) µg/dL ✅
b) mg/dL
c) mmol/L
d) ng/mL

Explanation: Lead is a common heavy metal; its blood concentration is a marker of exposure.

Cyanide poisoning can be detected by:
a) Blood cyanide level ✅
b) Urine glucose
c) CSF protein
d) Plasma electrolytes

Explanation: Cyanide inhibits cytochrome oxidase; lab measurement confirms exposure.

Organophosphate poisoning inhibits:
a) Acetylcholinesterase ✅
b) Amylase
c) Lactate dehydrogenase
d) Creatinine kinase

Explanation: Leads to accumulation of acetylcholine causing cholinergic symptoms.

Methanol poisoning can lead to:
a) Metabolic acidosis and visual disturbances ✅
b) Hyperglycemia
c) Leukopenia
d) Hypocalcemia

Explanation: Formic acid, the toxic metabolite, causes optic nerve damage and acidosis.

Serum ethanol concentration is measured by:
a) Enzymatic assay or gas chromatography ✅
b) Hemocytometer
c) ELISA only
d) TLC

Explanation: Accurate quantification is essential for legal and clinical management.

Therapeutic drug monitoring (TDM) is important for:
a) Drugs with narrow therapeutic index ✅
b) All vitamins
c) Antibiotics only
d) Electrolytes

Explanation: Ensures efficacy and prevents toxicity for drugs like digoxin, lithium, and aminoglycosides.

Common sample for toxicology analysis is:
a) Blood, urine, hair, and saliva ✅
b) Only blood
c) Only urine
d) Only CSF

Explanation: Choice depends on suspected toxin, route, and detection window.

Heavy metals commonly tested in toxicology include:
a) Lead, mercury, arsenic, cadmium ✅
b) Sodium, potassium
c) Glucose, urea
d) Hemoglobin only

Explanation: These metals accumulate in body tissues and cause chronic toxicity.

Poisoning with carbon monoxide is diagnosed by:
a) Carboxyhemoglobin levels in blood ✅
b) Hematocrit
c) CSF glucose
d) Blood urea

Explanation: CO binds to hemoglobin, reducing oxygen-carrying capacity.

Immunoassays in toxicology are used for:
a) Detection of drugs of abuse ✅
b) Electrolyte measurement
c) Blood cell count
d) Protein estimation

Explanation: Rapid, sensitive, and suitable for screening large populations.

Gas chromatography-mass spectrometry (GC-MS) is used in toxicology for:
a) Confirmatory detection of drugs and toxins ✅
b) Hematology
c) Biochemistry only
d) Cytology

Explanation: Gold standard for identification of unknown toxic substances.

Urine drug testing is preferred because:
a) Non-invasive and drugs remain longer ✅
b) Blood is better
c) Saliva is longer
d) CSF is easier

Explanation: Metabolites often persist in urine longer than in blood.

Paracetamol poisoning can be treated with:
a) N-acetylcysteine ✅
b) Atropine
c) Digoxin
d) Ethanol

Explanation: NAC replenishes glutathione and detoxifies NAPQI.

Toxicology analysis of hair is used to:
a) Detect chronic exposure ✅
b) Detect acute poisoning only
c) Detect electrolyte imbalance
d) Detect infection

Explanation: Drugs and metals are incorporated into hair over time, showing long-term exposure.

Acute alcohol poisoning affects:
a) CNS leading to coma or respiratory depression ✅
b) Only liver
c) Only kidneys
d) Only blood cells

Explanation: High ethanol levels depress the central nervous system.

LC-MS/MS (Liquid Chromatography-Tandem Mass Spectrometry) in toxicology is used for:
a) Sensitive and specific drug detection ✅
b) Blood cell count
c) Protein estimation
d) Glucose monitoring

Explanation: Modern advancement allowing precise quantification at low concentrations.

Poisoning with organophosphates is treated with:
a) Atropine and pralidoxime ✅
b) N-acetylcysteine
c) Calcium gluconate
d) Digoxin

Explanation: Atropine antagonizes muscarinic effects; pralidoxime reactivates acetylcholinesterase.

Clinical toxicology helps in:
a) Diagnosis, treatment, and prevention of poisoning ✅
b) Only prevention
c) Only diagnosis
d) Only treatment

Explanation: Lab data is critical for clinical decision-making.

Biological sample stability in toxicology depends on:
a) Storage temperature, container, preservative ✅
b) Patient diet
c) Time of day only
d) Sample volume only

Explanation: Proper handling prevents degradation of analytes.

Advanced automation in MLT includes:
a) Fully automated analyzers for hematology, chemistry, immunology ✅
b) Manual pipetting only
c) Only microscope work
d) Only reagent prep

Explanation: Automation increases throughput, precision, and reduces human error.

Point-of-care testing (POCT) in MLT:
a) Provides rapid results near patient ✅
b) Requires large central lab only
c) Not reliable
d) Only for research

Explanation: Useful in emergency and bedside testing.

Molecular diagnostics in MLT includes:
a) PCR, RT-PCR, NGS ✅
b) Only culture methods
c) Only staining
d) Only hematology

Explanation: Detects genetic mutations, infections, and drug resistance with high sensitivity.

High-throughput screening (HTS) in clinical labs:
a) Allows testing of thousands of samples rapidly ✅
b) Manual testing only
c) Slow batch testing
d) Only research

Explanation: Used in drug discovery and large-scale toxicology screening.

Lab-on-a-chip technology:
a) Miniaturized device integrating multiple tests ✅
b) Only for hematology
c) Only for microbiology
d) Only for biochemistry

Explanation: Reduces sample volume, time, and cost; advances point-of-care diagnostics.

Automation reduces:
a) Human errors and workload ✅
b) Instrument efficiency
c) Test accuracy
d) Sample quality

Explanation: Ensures standardized procedures with consistent results.

Digital microscopy in MLT helps in:
a) Remote analysis and telepathology ✅
b) Only manual slides
c) Only staining
d) Only reagent prep

Explanation: High-resolution imaging allows remote consultation and education.

Biosensors in toxicology are used for:
a) Rapid detection of toxins ✅
b) Measuring hematocrit only
c) Only culture identification
d) Only protein estimation

Explanation: Electrochemical or optical sensors provide real-time monitoring.

Tandem mass spectrometry (MS/MS) is used in:
a) Newborn screening and toxicology ✅
b) Only hematology
c) Only biochemistry
d) Only cytology

Explanation: Detects multiple analytes simultaneously with high specificity.

Nanotechnology in MLT enables:
a) Sensitive detection of biomarkers and toxins ✅
b) Only culture methods
c) Only manual pipetting
d) Only hematology

Explanation: Nanoparticles enhance assay sensitivity and reduce sample requirements.

Immunoassay advancements include:
a) Chemiluminescence, fluorescence, ELISA automation ✅
b) Only manual ELISA
c) Only colorimetric tests
d) Only blood counts

Explanation: Provides higher throughput and better reproducibility.

Automated coagulation analyzers measure:
a) PT, aPTT, fibrinogen, D-dimer ✅
b) Only RBC count
c) Only glucose
d) Only protein

Explanation: Automation reduces error and improves standardization in hemostasis testing.

Telepathology in MLT:
a) Enables remote slide review and consultation ✅
b) Only local lab use
c) Only manual microscopy
d) Only biochemistry

Explanation: Supports rapid expert opinion and education across distances.

Pharmacogenomics in clinical labs:
a) Tailors drug therapy based on genetic profile ✅
b) Only measures toxicity
c) Only detects infection
d) Only hematology

Explanation: Ensures safe and effective personalized medicine.

Multiplex assays allow:
a) Detection of multiple analytes in a single run ✅
b) Single analyte only
c) Only RBC count
d) Only WBC count

Explanation: Saves time and sample; useful in immunology and infectious disease testing.

Automation in toxicology improves:
a) Accuracy, reproducibility, and throughput ✅
b) Only cost
c) Only manual work
d) Only reagent prep

Explanation: Minimizes human errors and allows high-volume testing.

Environmental toxicology in MLT involves:
a) Monitoring exposure to pollutants and chemicals ✅
b) Only patient testing
c) Only hematology
d) Only microbiology

Explanation: Detects environmental hazards affecting human health.

Poison detection kits include:
a) Immunoassays, colorimetric strips ✅
b) Only ELISA
c) Only GC-MS
d) Only microscopy

Explanation: Rapid screening for drugs and toxins in emergency settings.

Clinical toxicology lab workflow includes:
a) Sample collection → preservation → analysis → interpretation ✅
b) Only analysis
c) Only collection
d) Only reporting

Explanation: Standardized workflow ensures accurate and reliable results.

Automated hematology analyzers provide:
a) CBC, reticulocyte count, WBC differential ✅
b) Only WBC
c) Only RBC
d) Only platelets

Explanation: Automation speeds up routine testing and reduces manual errors.

Multiplex PCR in toxicology:
a) Detects multiple pathogens or genes in one reaction ✅
b) Single target only
c) Only for RBC
d) Only for protein

Explanation: Useful for rapid infectious disease detection and genetic testing.

Next-Generation Sequencing (NGS) in MLT:
a) Detects genetic mutations, pathogens, and pharmacogenomics ✅
b) Only culture
c) Only ELISA
d) Only protein estimation

Explanation: Advanced tool enabling precision diagnostics.

Rapid diagnostic tests (RDTs) are:
a) Immunochromatographic tests for bedside use ✅
b) Only lab-based assays
c) Only PCR
d) Only cytology

Explanation: Provide quick, point-of-care detection of infections or toxins.

Automation reduces:
a) Turnaround time and manual errors ✅
b) Accuracy
c) Reliability
d) QC

Explanation: Increases lab efficiency and reproducibility.

Laboratory informatics includes:
a) LIS, data management, result reporting ✅
b) Only manual record keeping
c) Only microscopy
d) Only hematology

Explanation: Integrates sample tracking, result storage, and report generation.

Toxicology reference ranges are important for:
a) Interpreting drug and toxin levels ✅
b) Only QC
c) Only sample storage
d) Only reagent prep

Explanation: Guides clinical decision-making and management of poisoning.

Poison detection in hair indicates:
a) Chronic exposure ✅
b) Acute exposure only
c) Only protein levels
d) Only infection

Explanation: Toxins incorporate into hair over time, showing long-term exposure history.

Advances in MLT improve:
a) Accuracy, speed, safety, and patient care ✅
b) Only equipment cost
c) Only sample collection
d) Only QC

Explanation: Modern automation, molecular techniques, and informatics enhance overall laboratory efficiency and diagnostic reliability.

Frequently Asked Questions (FAQs) on MLT MCQs

1. Are these MLT MCQs useful for B.Sc MLT and DMLT exams?

✅ Yes. These MLT MCQs are designed for B.Sc MLT, DMLT, and other paramedical courses. The questions cover all core subjects such as Hematology, Biochemistry, Microbiology, Histopathology, and Blood Banking, which are part of most university and competitive exam syllabi. Practicing these MCQs will help students strengthen concepts and perform better in both theory exams and viva.

2. Do these MCQs include explanations or only answer keys?

✅ Unlike many resources that provide only answer keys, our MLT MCQs include detailed explanations. Each question is followed by the correct answer and a short explanation, helping students understand the reasoning behind the answer. This ensures conceptual clarity rather than rote memorization.

3. Are the questions updated for 2025 competitive exams?

✅ Yes. The collection is regularly updated for 2025 and upcoming exams. We include the latest topics, recent advances in laboratory technology, and frequently asked questions from past papers. This makes the MCQ set highly relevant for competitive exams, B.Sc MLT entrance tests, DMLT board exams, and job interviews.

4. Are these MLT MCQs helpful for competitive exams like AIIMS, PGIMER, or ESIC?

✅ Yes. These MCQs are relevant for paramedical entrance exams and job recruitment tests like AIIMS MLT, PGIMER MLT, ESIC paramedical exams, and state-level health department exams. The subject coverage ensures that candidates are well-prepared for national-level competition.

5. Do these MLT MCQs cover practical viva questions as well?

✅ Yes. Along with theory-based MCQs, this collection also includes practical and viva-oriented questions related to microscopy, staining, blood grouping, biochemistry tests, and microbiology techniques. This helps students prepare for both written exams and viva voce.

6. Can I use these MCQs for quick revision before exams?

✅ Definitely. The 1000+ MLT MCQs with answers PDF is designed for last-minute revision. Each question is concise, exam-focused, and arranged subject-wise, making it easy to cover all important topics in a short time.

7. Are these MLT MCQs helpful for AIIMS and PGIMER MLT exams?

✅ Yes. These MCQs cover AIIMS and PGIMER MLT exam syllabus, including Hematology, Biochemistry, Microbiology, Blood Banking, and Laboratory Techniques. Many questions are based on previous year AIIMS and PGIMER paramedical papers, making them highly relevant for preparation.

8. Do these MLT MCQs include previous year exam questions?

✅ Yes. This collection includes previous year MLT exam questions asked in AIIMS, PGIMER, ESIC, Railway MLT, and State paramedical recruitment exams. Practicing these ensures students are familiar with exam pattern and frequently repeated questions.

9. Can I use these MLT MCQs for ESIC and Railway Paramedical Exams?

✅ Absolutely. The ESIC paramedical exam and Railway MLT recruitment exam both focus on clinical laboratory practices, quality control, and applied microbiology. The MCQs provided here match the pattern and difficulty level of those exams.

10. How should I practice these MCQs for maximum competitive exam success?

✅ The best approach is:

Solve subject-wise MCQs first (Hematology, Biochemistry, Microbiology, etc.).
Review explanations to strengthen weak areas.
Attempt mixed mock tests with 100–200 MCQs to build speed and accuracy
📕 MLT Topic-Wise Notes (Flashcard eBook)
🎓 Designed for B.Sc MLT, DMLT & Competitive Exams
✅ Subject-wise notes: Hematology, Biochemistry, Microbiology, Pathology, Blood Bank & more
✅ Flashcard style → Easy to revise & remember
✅ Covers key definitions, methods, instruments & important points
✅ Instant PDF download – revise anytime, anywhere
👉 [Buy Now & Start Revising Smarter]

🏁 Conclusion

Preparing for Medical Laboratory Technology (MLT) exams requires both strong theoretical knowledge and practical problem-solving skills. This extensive collection of 1000+ MCQs with answers and detailed explanations covers all essential MLT subjects, including Hematology, Biochemistry, Microbiology, Histopathology, Cytopathology, Blood Banking, Body Fluids, Coagulation, and Quality Control.

By practicing these MCQs, students can:

Reinforce key concepts and laboratory principles.
Improve accuracy and speed in answering exam questions.
Identify strengths and weaknesses in different subjects.
Gain confidence for competitive MLT exams.

This organized, subject-wise approach ensures comprehensive coverage of the entire MLT syllabus, making it a one-stop resource for exam preparation. Consistent practice with these MCQs will help students excel in both theory and practical aspects of Medical Laboratory Technology.

Introduction to MLT MCQs

Hematology MCQs with Answers

Clinical Biochemistry MCQs with Answers

Microbiology MCQs with Answers

Histopathology & Cytopathology MCQs with Answers

Blood Bank & Immunohematology MCQs with Answers

Laboratory Techniques & Quality Control MCQs

Miscellaneous MLT MCQs

🌟 Why Choose Our MLT MCQs?

🩸 MLT MCQs – Hematology

Biochemistry MCQ for MLT

🦠 Microbiology MCQs

🦠 Virology & Mycology

🧬 Histopathology & Cytopathology

🩸 Blood Bank & Immunohematology MCQs

🧪 Quality Control MCQs in MLT

💧 Body Fluids MCQs for MLT Exam

☣️ Toxicology & Advances in MLT

Frequently Asked Questions (FAQs) on MLT MCQs

1. Are these MLT MCQs useful for B.Sc MLT and DMLT exams?

2. Do these MCQs include explanations or only answer keys?

3. Are the questions updated for 2025 competitive exams?

4. Are these MLT MCQs helpful for competitive exams like AIIMS, PGIMER, or ESIC?

5. Do these MLT MCQs cover practical viva questions as well?

6. Can I use these MCQs for quick revision before exams?

7. Are these MLT MCQs helpful for AIIMS and PGIMER MLT exams?

8. Do these MLT MCQs include previous year exam questions?

9. Can I use these MLT MCQs for ESIC and Railway Paramedical Exams?

10. How should I practice these MCQs for maximum competitive exam success?

🏁 Conclusion