Question

A person with blood group AB has
a. Antigen A and B on RBC's and both anti-A and anti- antibodies in plasma
b. Antigen A and B on RBCS but neither anti-A and anti-B antibodies in plasma
c. No antigen on RBCs but both anti-A and anti-B antibodies present in plasma
d. Antigen A on RBC's and antibodies in plasma

Answer 1

Hint: Previously in the olden days, whenever there is blood transfusion occurs, there is clumping of blood takes place in some individuals, while in others it may not happening, so in order to know the exact reasons so many research had done, and finally Karl Landsteiner, discovered antigens and antibodies of the blood.

Complete answer:
- Karl Landsteiner had discovered blood antigens and antibodies, and later he also discovered a system called ABO blood group system.
- He discovered that antigens are present on the surface of the RBC.
- While the antibodies are present in the serum of the cells.
- The blood group system is created based on the presence or absence of antigens and their antibodies and the name of the blood group is based on the presence of a type of antigen on the RBC.
- Antigens are – antigen A and antigen B.
- While antibodies are anti-A antibodies and anti b antibodies.
- If the blood group is A, it contains antigen A on the Surface of their RBC and anti b antibodies in the serum.
- If the blood group is B, it contains antigen B on the surface of their RBC and anti-A antibodies in the serum.
- If the blood group is AB, it contains both antigen A and antigen B on the surface of their RBC, and no antibodies in the serum.
- If the blood group is O, No antigen is present on the surface of their RBC, and it contains both anti antibodies and anti b antibodies in the serum.

Blood Group	Antigen	Antibody
A	A	Anti b
B	B	Anti a
AB	Both A and B	No antibodies
O	No antigens	Both anti a and anti b antibodies are present.

Hence, the correct answer is option (B).

Note: In the case of transfusion, agglutination occurs if the donor antibody and recipient antigen are same, so in case of donors and recipients, neither of their antigens and antibodies should not be same. And blood group o, is universal donors and blood group AB are universal recipients.