In guinea pigs, coat color is determined by a single gene wi…
In guinea pigs, coat color is determined by a single gene with two alleles. A guinea pig from a true-breeding black strain is mated with a guinea pig from a true-breeding white strain. The F1 progeny are all black. Two of the F1 progeny are mated with each other. What proportion of the black F2 offspring is expected to be homozygous?