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Explain how TWO processes that affect the gene pool of populations can lead to evolution. - HSC - SSCE Biology - Question 29 - 2020 - Paper 1
Question 29
Explain how TWO processes that affect the gene pool of populations can lead to evolution.
Worked Solution & Example Answer:Explain how TWO processes that affect the gene pool of populations can lead to evolution. - HSC - SSCE Biology - Question 29 - 2020 - Paper 1
Step 1
Process 1: Mutation
Answer
Mutation is a change in the DNA sequence that can introduce new genetic variations into a population's gene pool. These mutations can occur randomly, and some may provide a survival advantage, allowing individuals with these advantageous traits to reproduce more successfully. Over time, this leads to an increase in the frequency of these beneficial alleles in the gene pool, ultimately contributing to evolutionary changes.
Step 2
Process 2: Genetic Drift
Answer
Genetic drift is a mechanism that refers to random changes in allele frequencies within a population, especially in small populations. An example of genetic drift is the bottleneck effect, where a significant reduction in population size leads to a loss of genetic diversity. As a result, certain alleles may become more or less common purely by chance, which can significantly affect the gene pool over generations. This can lead to evolutionary changes as the gene pool becomes more homogenous.