Final answer:
The genotypic and phenotypic ratios from crossing a white-eyed male fruit fly with a heterozygous red-eyed female are both 1:1, resulting in half of the offspring having white eyes and the other half having red eyes.
Step-by-step explanation:
When crossing a white-eyed male fruit fly with a female that is heterozygous for red eye color, the genotypic ratio of the offspring would be 1:1, and the phenotypic ratio would also be 1:1. This arises because the female has one red-eye allele (dominant) and one white-eye allele (recessive), while the male has only the white-eye allele (recessive).
If we denote the red-eye allele as 'XW' and the white-eye allele as 'Xw', the heterozygous female's genotype is 'XWXw' and the male's genotype is 'XwY'. Using a Punnett square to predict the results, half of the offspring (males) will inherit the 'Xw' allele from the female and the 'Y' from the male, resulting in white eyes. The other half of the offspring (females) will inherit the 'XW' allele from the female and the 'Xw' allele from the male, which results in red eyes due to the presence of the dominant allele.