Pigment of chicken feathers is regulated by two genes, the gene for feather pigm
ID: 167077 • Letter: P
Question
Pigment of chicken feathers is regulated by two genes, the gene for feather pigment C, and a gene that inhibits pigment production, I. A mother chicken, who is homozygous recessive for gene c, and heterozygous for gene I, is crossed with a father chicken, who is heterozygous for the pigment gene, and heterozygous for gene I. Inhibition is dominant to uninhibited, pigmented feathers are dominant to unpigmented feathers.
A) What are the potential genotypes of the gametes produced by the mother for these two genes?
B) What are the potential genotypes of the gametes produced by the father for these two gametes?
C) What is the probability of one of the offspring of these two chickens having pigmented feathers?
In a population of 150 chickens, produced from the same parents, how many chickens would you expect to have white feathers? Round your answer to the lowest whole number since you cannot have a partial chicken, e.g. 65.8 would round to 65, as would 65.4, 65.5.
Explanation / Answer
Parental cross: ccIi X CcIi
Gametes: (cI) (ci) X (CI) (Ci) (cI) (ci)
Progeny: CCII CcIi ccII ccIi CcIi Ccii ccIi ccii
Progeny with pigmented feathers = 1/8 (Ccii)
Progeny with white feathers = 7/8
= 7/8 X 150
= 131.25
= 131