Inhibitors

Competitive inhibitors resemble the substrate and compete for the enzyme's active site. Increasing substrate concentration can overcome their effect. The other options describe irreversible inhibition or incorrect mechanisms. Concept tested: Competitive inhibition.

Competitive inhibition is reversible because substrate molecules can outcompete the inhibitor at high concentrations. Non-competitive and irreversible inhibitors cannot be overcome this way. Concept tested: Effect of substrate concentration on inhibition.