Please explain in detail how you get the answer In a species

Please explain in detail how you get the answer.

In a species of Drosophila, genes q and r are found on the same chromosome 20 centimorgans apart. A cross was made between the following individuals: What proportion of the offspring would you expect to have the wild-type phenotype (wild-type is denoted by the - alleles and is dominant to the mutant alleles)? Select one: 0.20 b. 0.10 0.40 None of these 0.80

Solution

q⁺rqr * qr⁺ qr

A Drossophila species with two genes q and r (wild type q+ and r+ ) is testcrossed to qr then the proportion of wild type phenotype;

^{is testcrossed to}

If the two genes q and r are 20 centimorgans apart then the 45 % of the progeny will be of wild type progeny q+r+ qr. Therefore the answer is b 0.10.

	is testcrossed to If the two genes q and r are 20 centimorgans apart then the 45 % of the progeny will be of wild type progeny q+r+ qr. Therefore the answer is b 0.10.