Biology

Thinking Dominant Means More Common

Students assume a dominant allele must be the allele found in most individuals.

Quick check

Why students make it

The word dominant sounds like strongest, best, or most common. In genetics, dominant only describes how an allele affects the phenotype when paired with another allele.

The rule done right

A dominant allele shows its trait in a heterozygote, such as AaAa. Allele frequency depends on inheritance, selection, mutation, migration, and chance, not on whether an allele is dominant or recessive.

Related resources

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