What is the effect of excess heat or temperature on an enzyme

An enzyme is a protein, and proteins need certain temperatures to function optimally, or even function. Temperature may unfold the protein and may stop its functioning, or it may fold the protein into the correct formation to function. But by the way your question asks, EXCESS heat would denature the enzyme and cease function.

Three reasons of the deaths of native americans: new illnesses that their immune systems couldn't cope with. genocides so the settlers could have the good land.starvation from lack of rations and poor infertile land on resevations

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