Consider the following statements:
A. Antigen 'A' and antibody 'a', and antigen 'B' and antibody 'b', cannot live together.
B. Blood group 'O' is called the universal donor.
C. Blood group 'AB' is called the universal recipient.
D. At the time of blood transfusion, the Rh factor is also tested.
E. The main function of blood platelets is to protect the body from disease.
Choose the most appropriate answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → A, B, C and D only
A person's blood group depends on the antigens (A, B) on the red blood cells and the antibodies (a, b) in the plasma; an antibody makes red cells carrying its own antigen clump together.
A. Antigen 'A' and antibody 'a', and antigen 'B' and antibody 'b', cannot live together. Correct. If antigen A and antibody a were in the same blood, the antibody would make the red cells clump (agglutinate). That is why group A blood carries antibody b and group B blood carries antibody a.
B. Blood group 'O' is called the universal donor. Correct. Group O red cells carry neither antigen A nor antigen B, so the antibodies of any receiver have nothing to act on.
C. Blood group 'AB' is called the universal recipient. Correct. Group AB plasma has neither antibody a nor antibody b, so it can receive red cells of any group.
D. At the time of blood transfusion, the Rh factor is also tested. Correct. An Rh-negative person given Rh-positive blood makes anti-Rh antibodies, which can cause a serious reaction at a later transfusion, so the Rh factor is matched too.
E. The main function of blood platelets is to protect the body from disease. Incorrect. Platelets help the blood to clot and stop bleeding from a wound; protecting the body from disease is the work of the white blood cells.