AP BIOLOGY

Detailed explanation-1: -By binding to an allosteric site, thus changing the shape of the active site of the enzyme. By decreasing the free-energy change of the reaction catalyzed by the enzyme. By binding to the substrate, thus changing its shape so that it no longer binds to the active site of the enzyme.

Detailed explanation-2: -Non-competitive inhibition [Figure 19.2(ii)] is reversible. The inhibitor, which is not a substrate, attaches itself to another part of the enzyme, thereby changing the overall shape of the site for the normal substrate so that it does not fit as well as before, which slows or prevents the reaction taking place.

Detailed explanation-3: -In noncompetitive inhibition, the inhibitor binds at an allosteric site separate from the active site of substrate binding. Thus in noncompetitive inhibition, the inhibitor can bind its target enzyme regardless of the presence of a bound substrate.

Detailed explanation-4: -Noncompetitive Inhibitors This changes the enzyme’s three-dimensional structure so that its active site can still bind substrate with the usual affinity, but is no longer in the optimal arrangement to stabilize the transition state and catalyze the reation.

Detailed explanation-5: -Noncompetitive inhibitors bind irreversibly to the enzyme and prevent the substrate-enzyme activity. This decreases the efficacy of the enzyme.