Blood Bank - Blood Group Systems Practice Questions
with Complete Solutions/ Latest Update 2026.
1. The most clinically significant blood group system in transfusion
medicine is:
A) Rh system
B) ABO system
C) Kell system
D) Duffy system
Correct Answer: B
Rationale: The ABO blood group system is the most important in
transfusion practice because ABO incompatibility can cause
severe, life-threatening hemolytic transfusion reactions. Unlike
many other systems, ABO antibodies are naturally occurring
(primarily IgM) and can cause immediate intravascular
hemolysis .
1
,2. The ABO blood group system was discovered in 1901 by:
A) Alexander Weiner
B) Karl Landsteiner
C) Ronald Fisher
D) William Morris
Correct Answer: B
Rationale: Karl Landsteiner discovered the ABO blood group
system in 1901. He observed that serum from group A
individuals agglutinated cells from group B, and vice versa, while
serum from group O agglutinated both A and B cells .
Landsteiner was awarded the Nobel Prize for this discovery.
3. According to Landsteiner's Rule, which of the following is TRUE?
A) Anti-A and anti-B are only present after transfusion
B) An individual's serum contains antibodies to the ABO antigens
present on their own red cells
C) An individual's serum contains antibodies to the ABO antigens
2
,NOT present on their own red cells
D) All individuals have no ABO antibodies in their serum
Correct Answer: C
Rationale: Landsteiner's Rule states that an individual lacks
antibodies to the antigens present on their own red cells. For
example, a group A individual has anti-B in their serum, while a
group O individual has both anti-A and anti-B .
4. What is the universal red blood cell donor?
A) Group A
B) Group B
C) Group AB
D) Group O
Correct Answer: D
Rationale: Group O red blood cells lack A and B antigens,
making them the universal red blood cell donor. This is because
3
, group O cells will not be agglutinated by anti-A or anti-B
antibodies present in the recipient's plasma .
5. What is the universal plasma donor?
A) Group A
B) Group B
C) Group AB
D) Group O
Correct Answer: C
Rationale: Group AB plasma contains no anti-A or anti-B
antibodies, making it the universal plasma donor. This is because
AB plasma will not cause hemolysis of A or B red cells .
6. The ABO gene is located on which chromosome?
A) Chromosome 1
B) Chromosome 9
4
with Complete Solutions/ Latest Update 2026.
1. The most clinically significant blood group system in transfusion
medicine is:
A) Rh system
B) ABO system
C) Kell system
D) Duffy system
Correct Answer: B
Rationale: The ABO blood group system is the most important in
transfusion practice because ABO incompatibility can cause
severe, life-threatening hemolytic transfusion reactions. Unlike
many other systems, ABO antibodies are naturally occurring
(primarily IgM) and can cause immediate intravascular
hemolysis .
1
,2. The ABO blood group system was discovered in 1901 by:
A) Alexander Weiner
B) Karl Landsteiner
C) Ronald Fisher
D) William Morris
Correct Answer: B
Rationale: Karl Landsteiner discovered the ABO blood group
system in 1901. He observed that serum from group A
individuals agglutinated cells from group B, and vice versa, while
serum from group O agglutinated both A and B cells .
Landsteiner was awarded the Nobel Prize for this discovery.
3. According to Landsteiner's Rule, which of the following is TRUE?
A) Anti-A and anti-B are only present after transfusion
B) An individual's serum contains antibodies to the ABO antigens
present on their own red cells
C) An individual's serum contains antibodies to the ABO antigens
2
,NOT present on their own red cells
D) All individuals have no ABO antibodies in their serum
Correct Answer: C
Rationale: Landsteiner's Rule states that an individual lacks
antibodies to the antigens present on their own red cells. For
example, a group A individual has anti-B in their serum, while a
group O individual has both anti-A and anti-B .
4. What is the universal red blood cell donor?
A) Group A
B) Group B
C) Group AB
D) Group O
Correct Answer: D
Rationale: Group O red blood cells lack A and B antigens,
making them the universal red blood cell donor. This is because
3
, group O cells will not be agglutinated by anti-A or anti-B
antibodies present in the recipient's plasma .
5. What is the universal plasma donor?
A) Group A
B) Group B
C) Group AB
D) Group O
Correct Answer: C
Rationale: Group AB plasma contains no anti-A or anti-B
antibodies, making it the universal plasma donor. This is because
AB plasma will not cause hemolysis of A or B red cells .
6. The ABO gene is located on which chromosome?
A) Chromosome 1
B) Chromosome 9
4
