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5 Cards in this Set
- Front
- Back
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What is the principle of selection?
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Organisms produce more offspring than can be supported by food etc.
Yet the population remains constant Hence, there is competition Some individuals will possess combinations of alleles that make the fitter to survive in competition These individuals are more likely to obtain resources and so grow more rapidly and live longer. They have a better chance of successfully breeding and produce more offspring Over time, the frequency of advantageous alleles increases , and non advantageous ones decrease |
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Advantageous alleles depend on...
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...the environment. While body only advantageous in a snowy landscape
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What are the two types of selection?
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Directional selection and stabilising selection
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What is directional selection?
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When selection favours individuals that vary in one direction from the mean of the population.
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What is stabilising selection?
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When average-Joe individuals are favoured :) - Preserves the characteristics of the population
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