Answer 1

In humans, the blood groups are controlled by a gene called gene ‘I’. It has three alleles, namely I^A, I^Band i.

Table Showing the Genetic Basis of Blood Grouping in Human Population

Allele from Parent 1	Allele from Parent 2	Genotype of Offspring	Blood-types of Offspring
IA	IA	IA IA	A
IA	IB	IA IB	AB
IA	i	IA i	A
IB	IA	IA IB	AB
IB	IB	IB IB	B
IB	i	IB i	B
i	i	i i	O