Biology / Unit 5 Bio 1031 short lesson, about 20 seconds
Dominant and Recessive Alleles
Captions available
The idea
A dominant allele's trait appears in a heterozygote and masks the recessive allele's trait, which appears only in a homozygous recessive genotype.
In practice
The yellow-seed allele Y is dominant over the green-seed allele y, so a Yy plant shows yellow seeds.
Where people slip
Dominance describes which trait shows in a heterozygote — it says nothing about which allele is more common in a population.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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