NEET BIOLOGY

Detailed explanation-1: -Of these three genotypes, only bb, the homozygous recessive genotype, will produce a phenotype of blue eyes. The heterozygous genotype and the homozygous dominant genotype both will produce brown eyes, though only the heterozygous genotype can pass on the gene for blue eyes.

Detailed explanation-2: -Brown eye colour is dominant over blue eye colour. Therefore, for the brown-eyed parents having blue-eyed child, the possibility is that both have heterozygous genotype i.e. Bb. Therefore, from the square below, it is clear that there is a 25% possibility of blue-eyed (bb) child.

Detailed explanation-3: -(c) Man is brown eyed, will have genotype Bb. The woman is blue-eyed will have genotypes bb. Thus the possible genotypes of their offsprings will be: Bb and bb.

Detailed explanation-4: -For example, when someone has brown eyes, it doesn’t necessarily mean they have homozygous genes. It’s possible for them to have a combination, or “Bb”, having one dominant brown allele and one recessive blue allele.