Question

Cross a heterozygous gray fur mouse with a homozygous white fur mouse what is the phenotype ratio for the possible F1 generation

Answer 1

The phenotype ratio for the offspring of a cross between a heterozygous gray fur mouse (Gg) and a homozygous white fur mouse (gg) would be 50% gray fur and 50% white fur, assuming fur color is not a sex-linked trait like the Drosophila eye color example.

Step-by-step explanation:

When considering a cross between a white-eyed male and a female that is heterozygous for red eye color, we are looking at an X-linked trait. In fruit flies (Drosophila melanogaster), eye color is a characteristic that is sex-linked, which means the gene controlling the trait is located on the X chromosome. Due to this fact, males have only one allele for the trait (since they have one X and one Y chromosome), while females have two alleles (since they have two X chromosomes).

For the student's question about mice, if gray fur is dominant (G) and white fur is recessive (g) and the cross is between a heterozygous gray fur mouse (Gg) and a homozygous white fur mouse (gg), then the phenotype ratio of their offspring would be:

• 50% gray fur (Gg)

50% white fur (gg)

This is similar to the Punnett square analysis in the given information about Drosophila eye color, but with fur color instead of eye color, and assuming fur color is not sex-linked.