Why are enzymes only secreted in specific locations of the digestive system?

Digestive enzymes are mostly produced in the pancreas, stomach, and small intestine. But even your salivary glands produce digestive enzymes to start breaking down food molecules while you're still chewing.

Explanation:

Digestive enzymes are released, or secreted, by the organs of the digestive system. These enzymes include proteases that digest proteins, and nucleases that digest nucleic acids. Examples of digestive enzymes are: Amylase, produced in the mouth.

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