A cross produces offspring in a 1 : 1 ratio of the dominant and recessive phenotypes. What were the parents' genotypes?

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Question

A cross produces offspring in a 1 : 1 ratio of the dominant and recessive phenotypes. What were the parents' genotypes?

Accepted Answer

One heterozygous and one homozygous recessive — Award 1 mark. The heterozygous parent supplies a dominant allele to half its gametes, and the other parent supplies only recessive alleles.

Answer

One homozygous dominant and one homozygous recessive

Answer

Both heterozygous

Answer

One heterozygous and one homozygous recessive

Answer

Both homozygous dominant

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