Question

in cats, black fur and green eyes are both dominant traits. Based on the dihybrid cross, answer the follow questions about the parental genotypes, phenotype probabilities, and the phenotypic ratio. What is the genotype of each parent.

Answer 1

If the cross is the standard dihybrid cross that yields the 9:3:3:1 phenotypic ratio, each parent must be heterozygous for both traits.
Let B = black (dominant), b = non-black; G = green (dominant), g = non-green.

Genotype of each parent: BbGg × BbGg

From that cross the phenotypic probabilities are:
- Black fur, green eyes = 9/16
- Black fur, non‑green eyes = 3/16
- Non‑black fur, green eyes = 3/16
- Non‑black fur, non‑green eyes = 1/16