Question

In cats, coat color is determined by allelic variation at a single autosomal locus, with black fur dominant to white fur. Two heterozygous black cats are mated. What would be the probability of the following combinations of offspring in a litter of eight kittens?
a) All with black fur.

b) Five with black fur and three with white fur.

c) At least three of the kittens having white fur.

d) The firstborn kitten with white fur, and among the remaining seven kittens, three with black fur and four with white fur.

Answer 1

Answer:

Explanation:

Two Heterozygous Black cats mated

let 'B' be for the Black allele and 'b' for the white allele

hence the mating will be : Bb * Bb = BB , Bb , Bb, bb, BB, Bb, Bb, bb

a) Determine the probability that all kittens out of 8 kittens are black

That means the kittens will have 'BB' or 'Bb' alleles

probability of Black fur = 3/4

b) probability of 5 black and 3 white

probability of black = 3/4

probability of white  = 1/4

hence probability of 5 black = 3/4 * 5 =