Question

Assertion (A): If a mother has two dominant alleles for black hair and father has two recessive alleles for blonde hair then their child will inherit one dominant allele from mother and one recessive allele from father and will have black hair.

Reason (R): Progeny inherits one genes for each trait from its parents but the trait shown by progeny depends on inherited alleles.

Options

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true but R is not the correct explanation of A.

• A is true but R is false.

• A is false but R is true.

Answer 1

Both A and R are true and R is the correct explanation of A.

Explanation:

The assertion is true because a child of a homozygous black-haired mother (BB) and a homozygous blonde-haired father (bb) inherits one allele from each parent, creating a heterozygous genotype (Bb) that expresses black hair due to dominance. The reason is also true and provides the correct explanation because it defines the foundational law of inheritance. Offspring receive one allele per parent for a given trait, and the final physical trait displayed depends directly on whether those inherited alleles are dominant or recessive.