Question

A forward mutation resulting in a green-eyed phenotype was generated in fruit flies by UV exposure. A second UV exposure, however, reversed that mutation as measured by the return of the wild-type phenotype. A researcher conducted a DNA analysis of these mutations. To her surprise, it revealed that the original "green-eye" mutation, which she identified as a nonsense mutation, was still retained in the now normal organism. Moreover, she identified a second mutation within a second gene, which was a tRNA gene. This researcher found evidence of a(n):

A. Silent mutation in the green-eye gene.
B. Intragenic suppressor mutation.
C. Neutral mutation in the green-eye gene.
D. Intergenic suppressor mutation.
E. Loss-of-function mutation in the tRNA gene.

Answer 1

The researcher found a silent mutation in the green-eye gene and a loss-of-function mutation in the tRNA gene.

Step-by-step explanation:

The researcher in this situation found evidence of a silent mutation in the green-eye gene and a loss-of-function mutation in the tRNA gene.

A silent mutation is a type of mutation that does not result in a change in the amino acid sequence of the protein. In this case, the original green-eye mutation was still retained in the organism, but it did not affect the phenotype of the eye color.

The loss-of-function mutation in the tRNA gene would result in a defective or non-functional tRNA molecule, which could lead to problems in protein synthesis.