Definition of Catalyst
Catalyst: A substance that speeds up a chemical reaction but is not consumed or altered in the process. Catalysts are of immense importance in chemistry and biology. All enzymes are catalysts that expedite the biochemical reactions necessary for life. The enzymes in saliva, for example, accelerate the conversion of starch to glucose, doing in minutes what would otherwise take weeks.
Last Editorial Review: 3/19/2012
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