Question

To get full credit, you have to show the work, complete and accurate. Presenting just the result gives you no credit at all. You need to prove you understand how to solve each problem.

7. In mice, the dominant T (tailless) allele results in a short tail. Consider a cross of TT+ ´ T+T+, where the symbol T+ represents that wildtype, non-mutant allele:

a. What are the expected proportions of tailless versus normal-tailed offspring?

b. In a litter consisting of 4 pups, what is the probability that two will be short-tailed and two normal-tailed?

8. In Drosophila, the recessive allele, dumpy (dp) results in short wings, and another recessive allele, rosy (ry) results in rosy eye color. A cross of between a dp dp+ ry ry+ female and a dp dp+ ry ry+ male yielded 79 wildtype, 29 rosy, 21 dumpy, and 15 rosy, dumpy progeny. Are these numbers consistent with a 9:3:3:1 ratio?

Answer 1