Phenotypes of Fruit Flies

[Steven7373]

This is another question off the practice exam that I cannot figure out. Any help would be greatly appreciated!

You have two pure-breeding lines of fruit flies. One line has four wings and the other is wild type. You mate a four-
winged female with a wild-type male. For each of the genetic hypotheses listed below, indicate the following.
a) The phenotype of male and female F1
b) The phenotype and proportions of each phenotype that would result from mating a F1 female back to its wild-type
male parent. Indicate the male and female phenotypes of this generation separately.

Genetic Hypothesis 1) Assume that the four-winged trait is due to an autosomal recessive maternal effect allele.


Genetic Hypothesis 2) Assume that the four-winged trait is due to an X-linked dominant allele.

Genetic Hypothesis 3) Assume that the four-winged trait is due to a mitochondrial DNA mutation.

[Cat]

Hint: F1 is heterozygous for Genetic Hypothesis 1; heterozygous/hemizygous for 2; and identical to F0 female line in 3.

Do the crosses and see what you come up with.

Good luck.

[mullet]

Hint: F1 is heterozygous for Genetic Hypothesis 1; heterozygous/hemizygous for 2; and identical to F0 female line in 3.

Thanks a mil, been searching everywhere for this answer!

[Harriett]

Lucky for scientists, and maybe not so lucky for fruit flies, there are all kinds of ways that fly DNA can be mutated to create interesting looking flies.Scientists can be very creative at this time.