Question

In Drosophila, the eye color gene is on the X chromosome. The red eyes allele (W) is dominant over the white eyes allele (w). If a red-eyed homozygous female is crossed with a white-eyed male, what is the genotypic ratio of the F2 generation?

Answer 1

Answer:

XWXw, XWXw, XWY, XWY

Explanation:

Since this is a X linked allele, homozygous red eyed female will be $X^{W}X^{W}$ and white eyed male will be $X^{w}Y$.

The offsprings will be $X^{W}X^{w}$, $X^{W}X^{w}$, $X^{W}Y$, $X^{W}Y$.

See the attached image for the Punnet's square analysis