Q1. What is the shelf life of whole blood collected in CPDA-1 anticoagulant?
A) 21 days
B) 35 days
C) 42 days
D) 28 days
Answer: B) 35 days
Explanation: CPDA-1 (Citrate Phosphate Dextrose Adenine) contains Adenine which helps maintain ATP levels, extending red blood cell shelf life to 35 days at $2-6^\circ\text{C}$.
Q2. At what temperature should Fresh Frozen Plasma (FFP) be stored?
A) $2^\circ\text{C}\text{ to }6^\circ\text{C}$
B) $-30^\circ\text{C}\text{ or colder}$
C) $20^\circ\text{C}\text{ to }24^\circ\text{C}$
D) $0^\circ\text{C}$
Answer: B) $-30^\circ\text{C}\text{ or colder}$
Explanation: FFP must be frozen at $-30^\circ\text{C}$ or below within 8 hours of collection to preserve labile clotting factors (Factor V and Factor VIII).
Q3. Major crossmatch involves testing between:
A) Donor Serum + Recipient RBCs
B) Donor RBCs + Recipient Serum
C) Donor Serum + Recipient Serum
D) Donor RBCs + Recipient RBCs
Answer: B) Donor RBCs + Recipient Serum
Explanation: Major crossmatch detects if recipient serum has antibodies against donor RBC antigens, preventing acute hemolytic reactions.
Q4. Which antigen is completely absent in individuals with Bombay Blood Group?
A) A antigen
B) B antigen
C) H antigen
D) D antigen
Answer: C) H antigen
Explanation: Bombay phenotype (hh) fails to express H antigen, which is the precursor for A and B antigens. Their serum contains strong Anti-H antibodies.
Q5. Direct Antiglobulin Test (DAT / Direct Coombs Test) detects:
A) Antibodies in serum
B) In vivo coated antibodies on RBCs
C) Antigens on RBCs
D) Free hemoglobin in urine
Answer: B) In vivo coated antibodies on RBCs
Explanation: DAT detects immunoglobulin (IgG) or complement bound to RBC surface in vivo (e.g., HDN, Autoimmune Hemolytic Anemia).
Q6. Cryoprecipitate is rich in which of the following clotting factors?
A) Factor II and IX
B) Factor VIII and Fibrinogen
C) Factor VII and X
D) Albumin
Answer: B) Factor VIII and Fibrinogen
Explanation: Cryoprecipitate contains concentrated Factor VIII, Fibrinogen, von Willebrand Factor (vWF), and Factor XIII.
Q7. Platelet concentrates should be stored at:
A) $2^\circ\text{C}-6^\circ\text{C}$ without agitation
B) $20^\circ\text{C}-24^\circ\text{C}$ with continuous agitation
C) $-20^\circ\text{C}$
D) $37^\circ\text{C}$
Answer: B) $20^\circ\text{C}-24^\circ\text{C}$ with continuous agitation
Explanation: Platelets require ambient temperature ($20-24^\circ\text{C}$) and constant agitation to prevent aggregation and maintain functional viability.
Q8. Additive solution SAGM increases the shelf life of PRBC to:
A) 28 days
B) 35 days
C) 42 days
D) 50 days
Answer: C) 42 days
Explanation: SAGM (Saline, Adenine, Glucose, Mannitol) prolongs RBC survival and stability up to 42 days.
Q9. Standard needle size (gauge) used for donor blood collection is:
A) 22-24 Gauge
B) 16-17 Gauge
C) 18-20 Gauge
D) 12 Gauge
Answer: B) 16-17 Gauge
Explanation: A wide-bore 16-17 gauge needle ensures rapid blood flow and prevents mechanical hemolysis of red blood cells during collection.
Q10. Anti-D immunoglobulin (RhoGAM) standard dose for Rh prophylaxis is:
A) 100 mcg
B) 300 mcg
C) 500 mcg
D) 50 mcg
Answer: B) 300 mcg
Explanation: Standard dose of 300 mcg intramuscular Anti-D neutralizes up to 15 mL of Rh-positive fetal red cells (30 mL whole blood).
Q11. Minimum hemoglobin level required for a blood donor in India is:
A) $10.0\text{ g/dL}$
B) $11.5\text{ g/dL}$
C) $12.5\text{ g/dL}$
D) $13.5\text{ g/dL}$
Answer: C) $12.5\text{ g/dL}$
Explanation: As per Indian Drug & Cosmetics Act regulations, both male and female blood donors must have a minimum Hb of $12.5\text{ g/dL}$.
Q12. Which antibody class is capable of crossing the placental barrier?
Answer: C) IgG
Explanation: IgG antibodies are small monomeric immunoglobulins that cross the placenta, causing Hemolytic Disease of the Fetus & Newborn (HDFN).
Q13. Lectin obtained from Dolichos biflorus plant agglutinates:
A) A1 RBCs
B) A2 RBCs
C) B RBCs
D) O RBCs
Answer: A) A1 RBCs
Explanation: Dolichos biflorus lectin serves as Anti-A1 reagent to differentiate A1 sub-group from A2 sub-group.
Q14. Lectin obtained from Ulex europaeus plant acts as reagent for:
A) Anti-A
B) Anti-B
C) Anti-H
D) Anti-D
Answer: C) Anti-H
Explanation: Ulex europaeus seeds yield Anti-H lectin, which reacts strongest with group O RBCs (highest concentration of H antigen).
Q15. Universal plasma donor blood group is:
A) Group O
B) Group AB
C) Group A
D) Group B
Answer: B) Group AB
Explanation: Group AB plasma contains neither Anti-A nor Anti-B antibodies, making it safe for transfusion to any ABO recipient.
Q16. Massive blood transfusion is defined as replacement of total blood volume within:
A) 12 hours
B) 24 hours
C) 48 hours
D) 6 hours
Answer: B) 24 hours
Explanation: Transfusion of $\ge 10$ units of whole blood/PRBCs within 24 hours is defined as massive blood transfusion.
Q17. Complication of massive blood transfusion due to anticoagulant toxicity is:
A) Hypercalcemia
B) Hypocalcemia
C) Hypernatremia
D) Hypokalemia
Answer: B) Hypocalcemia
Explanation: Excess citrate in stored blood chelates free ionized calcium in recipient circulation, leading to citrate toxicity / hypocalcemia.
Q18. Which method is used to differentiate true agglutination from Rouleaux formation?
A) Heating at $56^\circ\text{C}$
B) Saline replacement technique
C) Acid wash
D) Addition of albumin
Answer: B) Saline replacement technique
Explanation: Rouleaux stacks disperse upon adding normal saline, whereas true antigen-antibody agglutination remains intact.
Q19. Mandatory screening for donor blood in India includes all EXCEPT:
A) HIV 1 & 2
B) Hepatitis B & C
C) Dengue Virus
D) Syphilis & Malaria
Answer: C) Dengue Virus
Explanation: Mandatory testing list: HIV 1 & 2, HBsAg (HBV), Anti-HCV, Syphilis (VDRL/RPR), and Malaria parasite. Dengue is not routinely mandatory.
Q20. Irradiated blood components are transfused to prevent:
A) Acute Hemolytic Reaction
B) Transfusion-Associated Graft versus Host Disease (TA-GVHD)
C) Allergic Reactions
D) Febrile Reactions
Answer: B) Transfusion-Associated Graft versus Host Disease (TA-GVHD)
Explanation: Gamma irradiation (25 Gy) inactivates donor T-lymphocytes, preventing them from mounting TA-GVHD in immunocompromised recipients.
Q21. Thawing of Fresh Frozen Plasma (FFP) is done in a water bath at:
A) $20^\circ\text{C}-24^\circ\text{C}$
B) $37^\circ\text{C}$
C) $56^\circ\text{C}$
D) $4^\circ\text{C}$
Answer: B) $37^\circ\text{C}$
Explanation: FFP is rapidly thawed in a temperature-controlled $37^\circ\text{C}$ water bath to protect labile coagulation factors from degradation.
Q22. What is the deferral period for a donor after tattoo or body piercing?
A) 6 months
B) 12 months
C) 3 months
D) 2 years
Answer: B) 12 months
Explanation: A 12-month deferral avoids potential transmission of blood-borne pathogens like Hepatitis B, C, and HIV during window period.
Q23. Indirect Antiglobulin Test (IAT) is primarily used for:
A) Detecting antibodies bound to RBC in vivo
B) Antibody screening and crossmatching in vitro
C) Blood group genotyping
D) Platelet count estimation
Answer: B) Antibody screening and crossmatching in vitro
Explanation: IAT detects incomplete IgG antibodies present free in serum after artificial in vitro sensitization phase.
Q24. Universal red blood cell donor group is:
A) O Rh Positive
B) O Rh Negative
C) AB Rh Positive
D) AB Rh Negative
Answer: B) O Rh Negative
Explanation: O Rh Negative RBCs lack A, B, and D antigens, minimizing immune recognition by recipient antibodies.
Q25. Which enzyme is responsible for converting H antigen to A antigen?
A) N-acetylgalactosaminyl transferase
B) D-galactosyl transferase
C) L-fucosyl transferase
D) Glucosyltransferase
Answer: A) N-acetylgalactosaminyl transferase
Explanation: Gene A codes for N-acetylgalactosaminyltransferase, adding N-acetylgalactosamine to H precursor to form A antigen.
Q26. Gene B codes for which immunodominant sugar transferase?
A) N-acetylgalactosamine
B) D-Galactose
C) L-Fucose
D) D-Glucose
Answer: B) D-Galactose
Explanation: Gene B produces D-galactosyltransferase, transferring D-galactose sugar onto the H substrate.
Q27. Immunodominant sugar conferring H antigen specificity is:
A) D-Galactose
B) L-Fucose
C) N-acetylglucosamine
D) Sialic acid
Answer: B) L-Fucose
Explanation: FUT1 gene encodes fucosyltransferase, placing L-fucose onto terminal galactose of precursor chains to make H antigen.
Q28. Most common cause of Febrile Non-Hemolytic Transfusion Reaction (FNHTR) is:
A) ABO mismatch
B) Recipient antibodies against donor WBCs/cytokines
C) Bacterial contamination
D) IgA deficiency
Answer: B) Recipient antibodies against donor WBCs/cytokines
Explanation: FNHTR is driven by recipient antibodies directed against HLA antigens on donor leukocytes or accumulated cytokines in stored components.
Q29. Leukoreduction filters remove leukocytes to a level less than:
A) $1 \times 10^8$
B) $5 \times 10^6$
C) $1 \times 10^6$
D) $1 \times 10^4$
Answer: B) $5 \times 10^6$
Explanation: Standard leukoreduced blood unit contains fewer than $5 \times 10^6$ residual leukocytes to prevent FNHTR and CMV transmission.
Q30. Expected platelet count increment per unit of Random Donor Platelet (RDP) is:
A) $1,000 - 2,000/\mu\text{L}$
B) $5,000 - 10,000/\mu\text{L}$
C) $30,000 - 50,000/\mu\text{L}$
D) $100,000/\mu\text{L}$
Answer: B) $5,000 - 10,000/\mu\text{L}$
Explanation: One unit of RDP typically increases adult recipient platelet count by $5,000\text{ to }10,000/\mu\text{L}$.
Q31. Single Donor Platelet (SDP) collected via apheresis increases platelets by:
A) $5,000 - 10,000/\mu\text{L}$
B) $30,000 - 50,000/\mu\text{L}$
C) $10,000 - 15,000/\mu\text{L}$
D) $100,000/\mu\text{L}$
Answer: B) $30,000 - 50,000/\mu\text{L}$
Explanation: One SDP unit is equivalent to 6–8 RDP units and yields a platelet increase of $30,000\text{ to }50,000/\mu\text{L}$.
Q32. Anticoagulant used in blood collection bags prevents clotting by binding with:
A) Fibrinogen
B) Calcium ions ($\text{Ca}^{2+}$)
C) Thrombin
D) Prothrombin
Answer: B) Calcium ions ($\text{Ca}^{2+}$)
Explanation: Sodium citrate in blood bags chelates ionized calcium, blocking the coagulation cascade.
Q33. What is the main function of Dextrose present in blood bag anticoagulants?
A) Acts as an anticoagulant
B) Substrate for ATP synthesis / RBC metabolism
C) Maintains pH
D) Prevents bacterial growth
Answer: B) Substrate for ATP synthesis / RBC metabolism
Explanation: Dextrose (Glucose) provides energy source for glycolytic pathway to keep RBCs viable during storage.
Q34. Frozen Red Blood Cells glycerolized for long-term storage are kept at:
A) $-20^\circ\text{C}$
B) $-65^\circ\text{C}\text{ to }-80^\circ\text{C}$
C) $-4^\circ\text{C}$
D) $0^\circ\text{C}$
Answer: B) $-65^\circ\text{C}\text{ to }-80^\circ\text{C}$
Explanation: High-glycerol cryoprotectant allows red blood cells to be frozen and stored at $-65^\circ\text{C}$ to $-80^\circ\text{C}$ for up to 10 years.
Q35. Which Rh antigen is considered the most immunogenic?
A) C antigen
B) D antigen
C) E antigen
D) c antigen
Answer: B) D antigen
Explanation: Rh D antigen is highly immunogenic. Exposure of an Rh-negative person to Rh D positive blood triggers anti-D antibody formation in >80% cases.
Q36. DU testing (Weak D) is essential for confirming Rh negative status in:
A) All blood recipients
B) All blood donors
C) Emergency transfusions
D) Platelet donors
Answer: B) All blood donors
Explanation: Blood donors testing negative for Rh D with standard routine anti-D reagents must undergo Weak D (Du) testing via IAT to avoid immunizing Rh-negative recipients.
Q37. Reagent used as Coombs reagent (AHG) contains:
A) Anti-human IgG & Anti-C3d
B) Anti-A and Anti-B
C) Anti-D antibodies
D) Albumin 22%
Answer: A) Anti-human IgG & Anti-C3d
Explanation: Polyspecific Antiglobulin Reagent contains antibodies directed against human IgG immunoglobulins and C3d complement component.
Q38. High Speed Centrifugation (Heavy Spin) is used to separate:
A) Platelet Rich Plasma (PRP)
B) Cell-free Plasma & Packed Red Cells
C) Whole blood from donors
D) White cells only
Answer: B) Cell-free Plasma & Packed Red Cells
Explanation: Heavy spin ($5000\times g$) packs cells tightly at the bottom, leaving cell-poor plasma on top. Light spin ($2000\times g$) yields Platelet Rich Plasma.
Q39. Donor deferral period after treatment of Malaria is:
A) 3 months
B) 1 year
C) 3 years
D) Permanent
Answer: C) 3 years
Explanation: As per guidelines, individuals treated for malaria are deferred for 3 years after becoming asymptomatic.
Q40. What is the weight requirement for donating 450 mL of blood in India?
A) Minimum 45 kg
B) Minimum 55 kg
C) Minimum 60 kg
D) Minimum 50 kg
Answer: B) Minimum 55 kg
Explanation: Donors weighing $\ge 45\text{ kg}$ can donate 350 mL, whereas donors weighing $\ge 55\text{ kg}$ can safely donate 450 mL whole blood.
Q41. Acute Hemolytic Transfusion Reaction (AHTR) is primarily mediated by:
A) IgG antibodies
B) IgM antibodies
C) IgE antibodies
D) IgA antibodies
Answer: B) IgM antibodies
Explanation: ABO mismatch causes rapid intravascular hemolysis mediated by potent complement-fixing IgM isoagglutinins.
Q42. Transfusion Reaction displaying hives, itching, and rash without fever is:
A) FNHTR
B) Allergic Reaction
C) Anaphylactic Reaction
D) TRALI
Answer: B) Allergic Reaction
Explanation: Allergic reactions are IgE-mediated hypersensitivity responses against donor plasma proteins, presenting as urticaria and pruritus.
Q43. TRALI stands for:
A) Transfusion Related Acute Lung Injury
B) Transfusion Related Allergic Lung Infection
C) Toxic Reaction Associated Lung Illness
D) Transfusion Reactive Autoimmune Lung Injury
Answer: A) Transfusion Related Acute Lung Injury
Explanation: TRALI is non-cardiogenic pulmonary edema triggered by donor anti-HLA or anti-granulocyte antibodies reacting with recipient neutrophils.
Q44. Which anticoagulant is preferred for routine Blood Bank crossmatching sample tubes?
A) Sodium Fluoride
B) K2-EDTA or Plain Tube (Clot activator)
C) Heparin
D) Sodium Oxalate
Answer: B) K2-EDTA or Plain Tube (Clot activator)
Explanation: EDTA prevents in vitro complement activation while serum/plasma can be evaluated cleanly for ABO/Rh testing and antibody screening.
Q45. Proteolytic enzymes (e.g., Papain, Ficin) destroy antigen activity of:
A) Rh system
B) Duffy system (Fya, Fyb) and MNS system
C) ABO system
D) Kidd system
Answer: B) Duffy system (Fya, Fyb) and MNS system
Explanation: Enzyme treatment cleaves sialic acid residues, destroying Duffy (Fya, Fyb) and M, N, S antigens while enhancing Rh and Kidd antigens.
Q46. Secretor status (Se gene / FUT2) allows ABO soluble antigens to appear in:
A) Urine only
B) Body secretions like Saliva, Semen, Tears
C) RBC membrane only
D) Cerebrospinal fluid only
Answer: B) Body secretions like Saliva, Semen, Tears
Explanation: Se gene expresses soluble H antigen in secretions, which is converted to soluble A or B antigens depending on ABO genotype (~80% population are secretors).
Q47. Maximum allowable blood collection volume from a donor should not exceed:
A) 15% of total blood volume
B) 10.5 mL/kg of donor body weight
C) 20% of total blood volume
D) 500 mL regardless of weight
Answer: B) 10.5 mL/kg of donor body weight
Explanation: Maximum volume collected (including samples) should not exceed 10.5 mL/kg donor weight or 13% of total blood volume.
Q48. Celloidin/Glycerol is added to RBCs before deep freezing to act as a:
A) Preservative against bacteria
B) Cryoprotectant (prevents ice crystal cell lysis)
C) Color indicator
D) Clot activator
Answer: B) Cryoprotectant (prevents ice crystal cell lysis)
Explanation: Glycerol penetrates RBC membranes, lowering freezing point and preventing hyperosmotic intracellular ice crystal damage.
Q49. An individual with Blood Group A has:
A) A antigen on RBC and Anti-B in serum
B) B antigen on RBC and Anti-A in serum
C) Both A and B antigens
D) Neither antigen nor antibody
Answer: A) A antigen on RBC and Anti-B in serum
Explanation: According to Landsteiner's rule, Group A individuals express A antigen on red cells and possess naturally occurring Anti-B antibodies in plasma.
Q50. What is the shelf life of Cryoprecipitate after thawing?
A) 24 hours at $2-6^\circ\text{C}$
B) 4 to 6 hours at room temperature ($20-24^\circ\text{C}$)
C) 5 days
D) 12 hours
Answer: B) 4 to 6 hours at room temperature ($20-24^\circ\text{C}$)
Explanation: Once thawed at $37^\circ\text{C}$, cryoprecipitate must be kept at room temperature and transfused within 4–6 hours to maintain Factor VIII potency.