Biology GCSE
Dominant allele
What Dominant allele means in Biology GCSE, as defined for AQA.
Definitions of Dominant allele
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Reference: AQA
An allele that is always expressed when present, so in mice the dominant allele for fur colour ensures that trait is expressed even if a recessive allele is present.
An allele of which only one copy is needed for the feature to appear, and which causes polydactyly.
An allele that causes a disorder when at least one copy is present, so one copy is enough.
An allele whose effect is expressed in the phenotype even when only one copy is present.
Topics that use Dominant allele
- Genetic inheritance (AQA GCSE)
- Inherited disorders (AQA GCSE)
Related terms
Using Dominant allele in the exam
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