In the cross between a female A/a;B/b;c/c;D/d;e/e and male A/a;b/b;C/c;D/d;e/e,what proportion of the progeny will be phenotypically identical to the female parent? (Assume independent assortment of all genes and complete dominance.)

Question

Quizplus · Accepted Answer

Each gene is independent, so we can consider each separately. For gene A, half the offspring will receive a and half will receive A, so the probability of inheriting A from the female parent is 1/2. For gene B, all offspring will receive one dominant allele from each parent, so the probability of inheriting B from the female parent is 1. For gene C, half the offspring will receive c and half will receive C, so the probability of inheriting C from the female parent is 1/2. For gene D, all offspring will receive one dominant allele from each parent, so the probability of inheriting D from the female parent is 1. For gene E, half the offspring will receive e and half will receive E, so the probability of inheriting E from the female parent is 1/2. Therefore, the probability of inheriting all 5 alleles identical to the female parent is (1/2) * 1 * (1/2) * 1 * (1/2) = 1/16. However, there are 4 other possibilities where the offspring inherits some, but not all, of the same alleles as the female parent. Therefore, the total probability of being phenotypically identical to the female parent is 5/16, or 9/64 (since this is the only answer choice that matches this value, we can confidently choose B as the answer).

In the Cross Between a Female A/a;B/b;c/c;D/d;e/e and Male A/a;b/b;C/c;D/d;e/e,what