Final answer:
An enzyme is a biological catalyst that speeds up chemical reactions in living organisms.
Step-by-step explanation:
An enzyme is a biological catalyst. It is a type of protein that speeds up chemical reactions in living organisms, without being consumed or altered in the process. Enzymes work by lowering the activation energy required for a reaction to occur, allowing it to happen more quickly. For example, the enzyme amylase helps break down starch into glucose during digestion.
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