Skip to main content

Dominant and Recessive Alleles

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

A dominant allele's trait appears in a heterozygote and masks the recessive allele's trait, which appears only in a homozygous recessive genotype.

Show

The yellow-seed allele Y is dominant over the green-seed allele y, so a Yy plant shows yellow seeds.

Watch for

Dominance describes which trait shows in a heterozygote — it says nothing about which allele is more common in a population.