Assume that the allele for dark brown hair in dogs is d and the allele for light brown hair is d. what is the genotype of a dog that has light brown hair? a. dd b. dd c. dd d. dd

The correct answer is C. dd

Explanation:

As the allele of the dark brown hair is denoted by a capital letter(D) and of light brown hair by small letter(d) therefore dark brown hair allele is a dominant allele and light brown hair allele is recessive allele.

As recessive allele can only be expressed in the phenotype when it is present in homozygous condition in the offspring therefore the genotype of the dog having light brown hair would be dd.

                       D      d

                 D   DD   Dd

                 d   Dd    dd

Genotype DD and Dd will express dark brown hair as it has the dominant allele for dark brown hair.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.