Final answer:
The genotype of a white-eyed male fruit fly is XYY. When crossed with a heterozygous red-eyed female (XWXw), the offspring ratio is expected to be 50% red-eyed males (XWY), 50% white-eyed males (XYY), 50% heterozygous red-eyed females (XWXw), and 50% white-eyed females (XwXw).
Step-by-step explanation:
White-eyed Male Fruit Fly Genotype
In the case of Drosophila melanogaster, or the common fruit fly, eye color is a trait that is linked to the X chromosome. For a white-eyed male fruit fly, the genotype would be XYY, as males have only one allele for the X-linked characteristic and are therefore hemizygous. The wild-type allele for eye color is red (XW), which is dominant over the white eye color allele (Xw).
Expected Offspring Ratios
When a white-eyed male (XYY) is crossed with a female that is heterozygous for red eye color (XWXw), the expected offspring ratio would be as follows: the males will all receive the Y chromosome from their father and either a red (XW) or white (Xw) allele from their mother, resulting in 50% red-eyed males (XWY) and 50% white-eyed males (XYY). The females will receive one X chromosome from each parent, leading to 50% heterozygous red-eyed females (XWXw) and 50% white-eyed females (XwXw).