Question

Shell color in snails is controlled by a single gene locus with two alleles. heterozygous orange-shelled (ss snails are mated to homozygous recessive white-shelled (ss snails. what is the expected genotypic ratio of the offspring?

Answer 1

Using a punnet square we can compare the parents' genes. I will use the letter s to represent the shell color.

S s
s Ss ss

s Ss ss

We can now see that there is a fifty fifty chance the offspring will be either color.