Explain what an enzyme is and the lock and key hypothesis.

An enzyme is a biological catalyst that ensures important certain chemical reactions can take place. They speed up the rate of a reaction without being used up or changed. Maltase is an example of an enzyme that converts maltose, the substrate, into two molecules of glucose. An enzyme can only work on one specific substrate.The Lock and Key Hypothesis of Enzyme Action:The enzyme and substrate and collide with each other. The active site of the enzyme has a specific shape and is complementary in shape and charge to the substrate. The enzyme and substrate fit together like a lock and key and the reaction is catalyzed. The enzyme molecule is unchanged and can be used again with another substrate.