Blood groups and safe transfusion — practice questions

Question 1 · difficulty L1 · recall

A person with blood group A has on red cells:

• A. B antigen
• B. no A or B antigen
• C. A antigen
• D. both A and B antigens

Question 2 · difficulty L1 · recall

Haemolytic disease of a later Rh-positive fetus may occur when an Rh-negative mother becomes sensitised:

• A. erythroblastosis foetalis
• B. thalassaemia
• C. haemophilia
• D. sickle-cell disease

Question 3 · difficulty L1 · recall

A person with blood group A has which ABO antigen-antibody combination?

• A. Both A and B antigens with no antibodies
• B. B antigen on erythrocytes and anti-A antibodies in plasma
• C. A antigen on erythrocytes and anti-B antibodies in plasma
• D. No A or B antigens with both anti-A and anti-B antibodies

Question 4 · difficulty L2 · understanding

Why can an individual with blood group AB receive red blood cells from any ABO group when other compatibility requirements are satisfied?

• A. AB erythrocytes cannot undergo agglutination
• B. The erythrocytes lack both A and B antigens
• C. The blood contains both anti-A and anti-B antibodies
• D. The plasma lacks anti-A and anti-B antibodies

Question 5 · difficulty L3 · application

A person with group B blood urgently needs packed red blood cells. Which ABO donor group is compatible on the basis of the major red-cell antigens?

• A. Group B or group O
• B. Group A only
• C. Group AB only
• D. Group A or group AB

Question 6 · difficulty L3 · application

Why are group O red blood cells often described as universal donor cells in the ABO system?

• A. Their plasma contains neither anti-A nor anti-B antibodies
• B. They lack both A and B antigens on their surface
• C. They carry both A and B antigens
• D. They lack haemoglobin

Question 7 · difficulty L4 · analysis

An Rh-negative mother becomes sensitised to Rh antigen during a first pregnancy with an Rh-positive fetus. Why can a later Rh-positive pregnancy be at greater risk?

• A. ABO antibodies permanently disappear from maternal plasma
• B. The fetus stops producing haemoglobin after the first pregnancy
• C. Anti-Rh antibodies can cross the placenta and destroy fetal erythrocytes
• D. Rh antigen prevents placental formation

Question 8 · difficulty L5 · analysis

Recipient R has group A, Rh-negative blood. Four packed-red-cell units are available: A−, O−, A+, and AB−. Which pair is safest on ABO and Rh grounds?

• A. AB− and O−
• B. A+ and AB−
• C. O− and A+
• D. A− and O−