Question

The $F_2$ genotypic ratio of Mendel’s monohybrid cross is ___.

• A. 1:1
• B. 3:1
• C. 2:3
• D. 1:2:1

Answer 1

The correct option is D

1:2:1

In the second filial generation of a monohybrid cross, four offsprings are obtained. The phenotypic ratio of Mendel’s monohybrid cross $F_2$ progeny is 3:1. Three offsprings show the dominant phenotype and one shows the recessive phenotype. Out of the four types of individuals of the $F_2$ progeny- one is homozygous dominant (TT), two are heterozygous dominant (Tt) and one is homozygous recessive (tt). Thus the $F_2$ genotypic ratio of Mendel’s monohybrid cross is 1:2:1.