Question

The number of phenotypes in ABO blood group is:

• A. One
• B. Two
• C. Four
• D. Five

Answer 1

The correct option is C

Four

The correct option is C.

Explanation of the correct option:

1. Upon performing the crossing for the blood group of the ABO group, four phenotypes result, viz. A group, B group, O group, AB group.
2. A and B are codominant over O type.
3. AB is the universal recipient, while O is the universal donor.
4. Red blood cells from blood type A have A antigens on them, while the plasma contains anti-B antibodies.
5. Plasma from people with blood group B contains anti-A antibodies and B antigens.
6. Blood group O has both anti-A and anti-B antibodies in the plasma but no antigens.
7. Despite lacking antibodies, blood group AB contains both A and B antigens.

Final answer:

The number of phenotypes in the ABO group is four.