Question

Both male and female rats have genotype Bb. Based on the Punnett square, Carol concluded that the phenotypic ratio of the monohybrid cross is 2:1:1. What mistake did Carol make?

Answer 1

The ratio should be 1:2:1. Carol concluded that there are 2 homozygous dominant, 1 heterozygous, and 1 homozygous recessive.
However, it should be 1 homozygous dominant, 2 heterozygous, and 1 homozygous recessive.

Answer 2

Actually the ratio should be  3:1.