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Question
State and explain any three factors affecting allele frequency in populations.
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Solution
- Gene migration or gene flow: When migration of a section of population to another place and population occurs, gene frequencies change in the original as well as in the new population. New genes/alleles are added to the new population and these are lost from the old population. There would be a gene flow if this gene migration happens multiple times.
- Genetic drift: If the same change occurs by chance, it is called genetic drift. Sometimes the change in allele frequency is so different in the new sample of the population that they become a different species. The original drifted population becomes founders and the effect is called founder effect.
- Mutation: Microbial experiments show that pre-existing advantageous mutations when selected will result in the observation of new phenotypes. Over a few generations, this would result in speciation. Natural selection is a process in which heritable variations enabling better survival are enabled to reproduce and leave greater number of progeny.
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