Question

Genes R and Y follow independent assortment. If RRYY produce round yellow seeds and rryy produce wrinkled green seeds, what will be the phenotypic ratio of the F₂ generation?

Options

• Phenotypic ratio - 1 : 2 : 1

• Phenotypic ratio - 3 : 1

• Phenotypic ratio - 9 : 3 : 3 : 1

• Phenotypic ratio - 9 :7

Answer 1

Phenotypic ratio - 9 : 3 : 3 : 1

Explanation:

correct. Explanation: This is a classic Mendelian dihybrid cross involving the independent assortment of two genes (R and Y), where yellow colour is dominant over green and round seed shape over wrinkled seed shape.

Cross: RRYY × rryy → F₁: RrYy (round yellow) F₂ phenotypic ratio from RrYy × RrYy =

9 Round Yellow

3 Round Green

3 Wrinkled Yellow

1 Wrinkled Green

Hence, 9 : 3 : 3 : 1 is the correct ratio.