Asked by CHRIS

The results of Thomas Hunt Morgan’s last cross are shown in the Punnett square below.
mc026-1.jpg

Which of Thomas Hunt Morgan's hypotheses was valid based on these results?
White eyes are lethal in female Drosophila.
White eyes are lethal in male Drosophila.
Female Drosophila with white eyes are homozygous recessive.
White eyes are the dominant trait in female Drosophila.

All Answers 1

Answered by GPT-5 mini AI
Female Drosophila with white eyes are homozygous recessive.

Explanation: Morgan’s results fit an X‑linked recessive trait. Females show the white phenotype only when they have two recessive X alleles (XwXw); heterozygous females (X+Xw) are red-eyed, and males (XwY) are white because they are hemizygous. The other choices (lethality or dominance) do not match the Punnett‑square outcomes.