GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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scientists and selective breeding.
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genetic variation and environmental factors.
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environmental factors and social factors.
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selective breeding and genetic variation.
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Detailed explanation-1: -Sometimes the environment changes a gene-either its DNA sequence or its activity level. Either of these effects can change the proteins that are made from a gene, which in turn affects traits. Some harmful environmental factors can change a gene’s nucleotide sequence. For example, UV radiation can break DNA strands.
Detailed explanation-2: -Again, natural selection itself does not create new variation, it merely influences the proportion of existing variants. Most forms of selection reduce the amount of genetic variation within populations, which may be counteracted by the continual emergence of new variation via undirected mutation and recombination.
Detailed explanation-3: -The essence of Darwin’s theory is that natural selection will occur if three conditions are met. These conditions, highlighted in bold above, are a struggle for existence, variation and inheritance.
Detailed explanation-4: -A number of environmental factors can impact natural selection. Climate, habitat type, available food, and a habitat’s predators can all impact which traits will be selected.