Final answer:
Competitive inhibition involves a competitive inhibitor binding to the enzyme's active site, preventing the substrate from binding and thus hindering the enzyme's catalytic action. This type of inhibition can be overcome by increasing substrate concentration, distinguishing it from noncompetitive inhibition that affects enzyme activity through allosteric interaction.
Step-by-step explanation:
Competitive inhibition of enzymes occurs when a substance other than the correct substrate binds at the active site of an enzyme. This substance, referred to as a competitive inhibitor, is structurally similar to the substrate, which allows it to fit into the active site and compete with the substrate for binding. However, because the inhibitor cannot undergo the same chemical reaction as the substrate, it simply blocks the active site and prevents the enzyme from catalyzing the reaction. The presence of competitive inhibitors slows down the reaction rate, but the inhibition can be overcome at high substrate concentrations, where the increased amount of substrate outcompetes the inhibitor for the active site. Unlike competitive inhibition, noncompetitive inhibition involves an inhibitor binding to an allosteric site on the enzyme, inducing a conformational change that affects the enzyme's activity even without directly blocking the active site.