The active site of an enzyme is the part that
A) temporarily combines with the eventual product of an enzyme-catalyzed reaction.
B) temporarily combines with a specific part of the substrate,forming an enzyme-substrate complex.
C) temporarily combines with a specific part of another enzyme molecule to speed up an enzyme-catalyzed reaction.
D) helps to slow down an enzyme-catalyzed reaction.
E) must be frequently replaced.

Question

Quizplus · Accepted Answer

The active site of an enzyme is the specific region of the enzyme's protein structure that temporarily combines with a specific part of the substrate. This forms an enzyme-substrate complex that allows the enzyme to catalyze a chemical reaction. Option A is incorrect because the active site does not combine with the eventual product but rather the substrate. Option C is incorrect because enzymes do not typically interact with other enzyme molecules. Option D is incorrect because the active site facilitates the reaction, it does not slow it down. Option E is incorrect because the active site is a permanent part of the enzyme molecule and is not replaced frequently.

The Active Site of an Enzyme Is the Part That