continuous variation
What continuous variation means in Biology A-Level, as defined for AQA, OCR.
Definitions of continuous variation
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Reference: OCR
A smooth range of phenotypes, such as human height or mass, usually polygenic with many genes each having a small additive effect, plus environmental influence, giving a normal distribution.
A characteristic that varies across a range because many genes each make a small contribution and the environment adds more.
Topics that use continuous variation
- Evolution may lead to speciation (A-level only) (AQA A-Level)
- Patterns of inheritance (OCR A-Level)
Related terms
- discontinuous variation
- genetic drift
- random fertilisation
- Allele frequencies
- allele frequency change
- Alleles, genotypes and phenotypes
- allopatric speciation
- Autosomal linkage
Using continuous variation in the exam
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