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In the Punnett square, what is the probability that an offspring would have triangular eyes?

User DRiFTy
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Final answer:

The offspring ratio is 25% heterozygous females with red eyes, 25% homozygous recessive females with white eyes, 25% hemizygous dominant males with red eyes, and 25% hemizygous recessive males with white eyes. Hence, there is a 50% chance for red eyes and a 50% chance for white eyes among the offspring.

Step-by-step explanation:

The question asks about the probability of eye color in offspring, using a Punnett square for a genetic cross. To answer this, consider that eye color in fruit flies is a sex-linked trait. If we use 'XR' to represent the allele for red eyes and 'Xr' for white eyes, a white-eyed male would have the genotype 'XrY' and a heterozygous female would have the genotype 'XRXr'. Setting up the Punnett square, we can determine the possible genotypes of their offspring.

After crossing 'XrY' with 'XRXr', the resulting genotypes are:

  • 25% 'XRXr' - Female, red eyes (heterozygous)
  • 25% 'XrXr' - Female, white eyes (homozygous recessive)
  • 25% 'XRY' - Male, red eyes (hemizygous dominant)
  • 25% 'XrY' - Male, white eyes (hemizygous recessive)

Therefore, the ratio of offspring with red and white eyes would be 50% with red eyes and 50% with white eyes, considering both male and female offspring.

User Sudana
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