Q. 2.  Can a child have blood group 'O' if his parents have blood group 'A' and 'B' Explain?


A child have blood group O in the following two cases
Case I when father is IA i and mother is IB i.

The offsprings will have the above possible blood groups. i.e., AB, A, B and O 
Case II when father is IB i and mother is IA i.

The offspring will have the above possible blood groups, i.e., AB, A, B and O. Thus, a child can have blood group 'O' if parents have heterozygous alleles for group 'A' and 'B'.