In Drosophila that exhibit the Lobe eye mutation,some heterozygous flies have tiny compound eyes,whereas others have large,lobulated eyes and between these extremes,there is a full range of phenotypes.This mutation is said to have:
A) Incomplete penetrance
B) Complete penetrance
C) Complete expressivity
D) Variable expressivity
E) None of these

Question

Quizplus · Accepted Answer

The fact that the Lobe eye mutation displays a range of phenotypes ranging from tiny compound eyes to large, lobulated eyes suggests that it has variable expressivity. Incomplete penetrance would refer to the situation where the mutation is present but the corresponding phenotype is not always expressed, and complete penetrance would refer to the situation where all individuals with the mutation exhibit the corresponding phenotype. Complete expressivity would refer to the situation where all individuals with the mutation exhibit the phenotype to the same degree or extent, which is not the case with the Lobe eye mutation.

In Drosophila That Exhibit the Lobe Eye Mutation,some Heterozygous Flies