Question

A plant of $F_1$-generation has genotype "AABbCC". On selfing of this plant, what is the phenotypic ratio in $F_2$-generation:

• A. 3: 1
• B. 1: 1
• C. 9 : 3 : 3: 1
• D. 27: 9: 9: 9 : 3 : 3 : 3: 1

Answer 1

The correct option is A 3: 1

Selfing is the process of fertilisation of the male and female gametes of the same individual.
AABbCC will produce two type of gametes ABC and AbC.
Thus in the F₂ generation, three genotypes will be obtained.
These are AABBCC, AABbCC, and AAbbCC in the ratio of 1: 2: 1.
Phenotypically AABBCC and AABbCC are same. So the phenotypic ratio in the F₂ generation will be 3: 1.