NEET BIOLOGY

Detailed explanation-1: -In a dihybrid cross, if you get 9:3:3:1 ratio it denotes that the alleles of two genes are segregating independently. This ratio is obtained when both the parents are heterozygous for both the genes.

Detailed explanation-2: -This 9:3:3:1 phenotypic ratio is the classic Mendelian ratio for a dihybrid cross in which the alleles of two different genes assort independently into gametes.

Detailed explanation-3: -So the correct option is “The alleles of two genes are segregating independently.".

Detailed explanation-4: -The hypothesis that color and shape genes assort independently thus predicts that the F2 generation will display a 9:3:3:1 phenotypic ratio: nine individuals with round, yellow seeds, three with round, green seeds, three with wrinkled, yellow seeds, and one with wrinkled, green seeds.

Detailed explanation-5: -The probabilities of different offspring genotypes and phenotypes can be determined using a Punnett square. A dihybrid cross results in a roughly 9:3:3:1 ratio of offspring phenotypes.