In a cross between a female Drosophila homozygous for a recessive mutant maternal-effect gene (m^-/m^-) and a wild-type male (m⁺/m⁺), the percentage of progeny that show normal development will be A) 0 per cent. B) 25 per cent. C) 50 per cent. D) 75 per cent. E) 100 per cent.

Question

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In a maternal-effect gene, the phenotype of the offspring is determined by the genotype of the mother. Since the mother is homozygous recessive (m-/m-), all progeny will show the mutant phenotype regardless of their own genotype.

In a Cross Between a Female Drosophila Homozygous for a Recessive