Question

11. The offspring of a cross between two rough-coated animals shows a ratio of three rough-coated offspring to one smooth-coated. Which trait must be dominant?​

Answer 1

The rough-coated trait must be dominant. This is because in a cross between two animals that are heterozygous for a particular trait (one dominant allele and one recessive allele), the ratio of dominant to recessive traits in the offspring is typically 3:1. If the smooth-coated trait were dominant, then all the offspring would have that trait, and the ratio would be 0:4 instead of 3:1.