The genotypes and phenotypes that result from a cross of AA and Aa (A = normal pigmentation and a = albinism) are
A. phenotypes:all normal; genotypes:50% homozygous dominant and 50% heterozygous.
B. phenotypes:50% normal and 50% albino; genotypes:all heterozygous.
C. phenotypes:all albino; genotypes:50% heterozygous and 50% homozygous recessive.
D. phenotypes:75% normal and 25% albino; genotypes:75% heterozygous and 25% homozygous.
Answer: A
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