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Why is the active site of enzymes important?

Answer:
The active site of an enzyme us the site that recognizes and binds to said enzyme's substrate. In biochemistry, a substrate is the molecule an enzyme acts upon, hence it follows that if an enzyme has lost its active site (or it has been deleteriously modified by a mutation), it will not be able to catalyze its function.
First answer by Tycho. Last edit by Tycho. Contributor trust: 19 [recommend contributor recommended]. Question popularity: 2 [recommend question].