A long-winged Drosophila female with a gray body mates with a black, short-winged male fly. The phenotypic ratio of the offspring is 1:1:1:1. What is the genotype of the female fly?

Explanation:

To obtain a phenotypic ration of 1:1:1:1 one of the parent must be heterozygous for both the trait and other parent must be homozygous recessive for both the trait.

If the long winged Drosophila with gray body is dominant then, it is represented by these genotype- LLGG, LlGG, LlGg and LLGg. Short and black Drosophila is considered as recessive (llgg)

Different crosses were carried to obtain a phenotypic ratio of 1:1:1:1.

So, if we cross LlGg with llgg we obtain a phenotypic ratio of 1:1:1:1

we obtain Drosophila which are

Long gray (4)

Long black (4)

Short gray (4)

Short black (4)

So, ratio comes out to be 1:1:1:1