Question

A person with blood group AB is considered a universal recipient because he has

• A. Both $A$ and $B$ antigens in the plasma but no antibodies.
• B. Both $A$ and $B$ antigens on $RBC$ but no antibodies in the plasma.
• C. Both $A$ and $B$ antibodies in the plasma.
• D. No antigen on $RBC$ and no antibody in the plasma.

Answer 1

Answer: (B)

Karl Landsteiner reported the ABO blood groups in humans in the year 1900. People with blood group A have the antigen A on the surface of their RBCs, and antibodies to antigen B in their plasma. Persons with blood group B have antigen B on their RBCs, and antibodies against antigen A in their plasma. Individuals with blood group AB have both antigen A and antigen B on their RBCs, and no antibodies for either of the antigens in their plasma. Type O individuals are without A and B antigens on their RBCs, but have antibodies for both these antigens in their plasma. Individuals with blood group AB can receive the blood of A, B, or O group (universal recipient), while those with blood group O can donate blood to anyone (universal donor). If a blood transfusion is made between an incompatible donor and recipient, the reaction of antigens on the cells and antibodies in the plasma produces clots that clog capillaries. The possible safe transfusions are mentioned in the table below.