AP Biology / Unit 7: Natural Selection
7.4 Population Genetics
Notes
Evolution is a change in allele frequencies in a population.
- Mutation adds new alleles.
- Genetic drift: random changes, strongest in small populations (bottleneck, founder effect).
- Gene flow: migration moves alleles between populations.
Practice
A storm randomly kills 90% of a population. This is:
Random survival.
Genetic drift has the strongest effect in:
Chance matters more.
Migration between populations tends to:
Gene flow mixes alleles.
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