Question

Fruit flies (Drosophila melanogaster) with a wild-type phenotype have gray bodies and red eyes. Certain mutations can cause changes to these traits. Mutant flies may have a black body and/or cinnabar eyes. To study the genetics of these traits, a researcher crossed a truebreeding wild-typed male fly with a true-breeding female fly with a black body and cinnabar eyes. All of the F1 progeny displayed a wild type phenotype. Which of the following is correct about the traits observed?a. Gray body and cinnabar eyes are dominant.b. Eye color is sex-linked.c. Body color is sex-linked.d. Gray body and red eyes are dominant.

Answer 1

Answer:

d

Explanation:

The correct answer would be that gray body and red eyes are dominant.

The wild type trait  is represented by gray bodies and red eyes while the mutant trait  is represented by black body and/or cinnabar eyes. A cross between the wild type and the mutant only yield F1 offspring with wild type phenotype. This, thus, means that the wild type trait is dominant while the mutant trait is recessive.

Since the wild type trait is depicted by gray body and red eyes, it means that the gray body and red eyes traits are dominant while the black body and cinnabar eyes are recessive.

The correct option is d.