A state of biological balance, or _HOMEOSTASIS_, is important for the survival of individual cells and _the whole organism_ alike.
Genetic variation<span> is essential for </span>natural selection<span> because </span>natural selection can only increase or decrease frequency of alleles that already exist in the population.Genetic variation<span> is caused by: mutation
i pulled this off of the site i got the information from i hope this helps you out if not sorry
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