Question

In summer squash, white fruit color (W) is dominant over yellow fruit color (w) and disk-shaped fruit (D) is dominant over sphere-shaped fruit (d).. If a squash plant true-breeding for white, disk-shaped fruit is crossed with a plant true-breeding for yellow, sphere-shaped fruit, what will the phenotypic and genotypic ratios be for:

a. the F1 generation? b. the F2 generation?

Answer 1

F1 generation ratio:1:2

Phenotypic ratio:9:3:3:1

Genotypic ratio:1:2:1:4:2:1:2:1

Explanation:

• When the white disk shaped fruit (WWDD) is crossed with yellow sphere shaped fruit (wwdd) the resulting generation will be the F1 generation or it is the first resulting generation from the cross

• F1 generation is also called as the first filial generation and the resulting will be white disk shaped fruit( WwDd)

• In F2 generation two ratios are given they are the genotypic ratio and the phenotypic ratio and this is obtained from the second cross

• The genotypic ratio will be 1:2:2:1:4:2:1:2:1

• The phenotypic ratio will be given as 9:3:3:1

• When the homozygous and the heterozygous are crossed this relationship is obtained

Answer 2

Answer:

In summer squash, white fruit color (W) is dominant over yellow fruit color (w) and disk-shaped fruit (D) is dominant

over sphere-shaped fruit (d). If a squash plant true-breeding for white, disk-shaped fruit is crossed with a plant true-

breeding for yellow, sphere-shaped fruit, what will the phenotypic and genotypic ratios be?

Explanation: