Indicate whether each of the following describes a competitive or a noncompetitive inhibitor.
e. Adding more substrate to the reaction restores the enzyme activity.

Verified step by step guidance

1. Understand the two types of enzyme inhibitors: Competitive inhibitors bind to the active site of the enzyme, competing with the substrate, while noncompetitive inhibitors bind to a different site on the enzyme, altering its function without directly competing with the substrate.
2. Recognize that in the case of competitive inhibition, increasing the concentration of the substrate can outcompete the inhibitor for the active site, restoring enzyme activity.
3. In contrast, for noncompetitive inhibition, increasing the substrate concentration does not restore enzyme activity because the inhibitor affects the enzyme's function regardless of substrate presence.
4. Analyze the statement: 'Adding more substrate to the reaction restores the enzyme activity.' This suggests that the inhibitor's effect can be overcome by increasing substrate concentration, which is characteristic of competitive inhibition.
5. Conclude that the described scenario corresponds to a competitive inhibitor, as the enzyme activity is restored by adding more substrate.

Key Concepts

Competitive Inhibition

Competitive inhibition occurs when an inhibitor competes with the substrate for binding to the active site of an enzyme. This type of inhibition can be overcome by increasing the concentration of the substrate, as more substrate molecules can outcompete the inhibitor for the active site, thereby restoring enzyme activity.

Noncompetitive Inhibition

Noncompetitive inhibition happens when an inhibitor binds to an enzyme at a site other than the active site, altering the enzyme's function regardless of substrate concentration. In this case, adding more substrate does not restore enzyme activity, as the inhibitor's presence affects the enzyme's ability to catalyze the reaction.

Enzyme Activity

Enzyme activity refers to the rate at which an enzyme catalyzes a reaction. It can be influenced by various factors, including substrate concentration, temperature, pH, and the presence of inhibitors. Understanding how inhibitors affect enzyme activity is crucial for determining the type of inhibition occurring in a biochemical reaction.