Final answer:
The phenotypic ratio for the offspring of a cross between a white-eyed male and a heterozygous red-eyed female is 1:1, with an equal probability of red-eyed to white-eyed offspring, assuming a simple dominant-recessive gene relationship and not a sex-linked trait.
Step-by-step explanation:
When considering the phenotypic ratio resulting from a cross between a white-eyed male and a female that is heterozygous for red eye color, we can predict the offspring's possible phenotypes using a Punnett square. Since the question appears to describe a trait determined by a single gene with two alleles, where red eye color is dominant (R) and white is recessive (r), we ascertain that the white-eyed male's genotype is rr and the heterozygous red-eyed female's genotype is Rr.
Crossing these genotypes, the Punnett square shows four possible offspring genotypes:
- Female heterozygous (Rr) - red-eyed
- Female homozygous recessive (rr) - white-eyed
- Male heterozygous (Rr) - red-eyed
- Male homozygous recessive (rr) - white-eyed
Each of these genotypes occurs with an equal probability of 25%, resulting in the phenotypic ratio of
1:1
for red-eyed to white-eyed offspring, assuming eye color is not sex-linked. However, if this is a sex-linked trait in species like fruit flies, where males are XY and females are XX, the ratio would differ. But based on the information provided, we are considering a simple dominant-recessive relationship, not sex linkage.