Variation means difference in genetic makeup between individuals within a specie.
Trial and Error
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Fermentation is the process that releases energy without using oxygen . In cellular respiration, anaerobic fermentation contrasts with aerobic cell respiration. Both processes convert glucose from food into adenosine triphosphate for energy for cells.
Explanation:
Speciation occurs when a group within a species separates from other members of its species and develops its own unique characteristics. The demands of a different environment or the characteristics of the members of the new group will differentiate the new species from their ancestors.
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