Question

3. In crosses b, d, and e of Problem 1, indicate how many of the gray progeny pro-

duced by each cross would be expected to produce white progeny when self-ferti-
lized?

Answer 1

To answer this question, we need to refer back to the results of Problem 1 for crosses b, d, and e. From that problem, we know that:

• Cross b: 3/4 of the progeny are gray and 1/4 are white.
• Cross d: All of the progeny are gray.
• Cross e: 1/2 of the progeny are gray and 1/2 are white.

For each cross, we can calculate the expected number of gray progeny that would produce white progeny when self-fertilized by multiplying the proportion of gray progeny by the proportion of white progeny expected from self-fertilization. This can be expressed as:

• Expected number of gray progeny producing white progeny = (Proportion of gray progeny) x (Proportion of white progeny from self-fertilization)

Using this formula, we can calculate the expected number of gray progeny producing white progeny for each cross:

• Cross b: (3/4) x (1/4) = 3/16 of the gray progeny are expected to produce white progeny.
• Cross d: Since all of the progeny are gray, none of them are expected to produce white progeny.
• Cross e: (1/2) x (1/2) = 1/4 of the gray progeny are expected to produce white progeny.

Therefore, in cross b, 3/16 of the gray progeny are expected to produce white progeny when self-fertilized. In cross d, none of the progeny are expected to produce white progeny when self-fertilized. In cross e, 1/4 of the gray progeny are expected to produce white progeny when self-fertilized.