In which kind of monohybrid cross would you expect to find a phenotypic ratio of 3:1 among the offspring?
A) heterozygous × heterozygous
B) homozygous recessive × homozygous recessive
C) homozygous dominant × homozygous dominant
D) homozygous recessive × homozygous dominant
E) homozygous dominant × heterozygous

Question

Quizplus · Accepted Answer

A phenotypic ratio of 3:1 is characteristic of a monohybrid cross between two heterozygous individuals (Aa × Aa). In this scenario, each parent carries one dominant allele (A) and one recessive allele (a). The possible genotypes of their offspring are AA, Aa, and aa. Phenotypically, the dominant allele masks the recessive allele, so AA individuals and Aa individuals will both display the dominant phenotype, while only the aa individuals will display the recessive phenotype. The ratio of dominant (AA + Aa) to recessive (aa) offspring is therefore 3:1.

In Which Kind of Monohybrid Cross Would You Expect to Find