Final answer:
Competitive inhibitors are unique in that they can reversibly bind to an enzyme's active site, and increasing the substrate concentration can overcome their inhibitory effects, potentially restoring enzyme activity.
Step-by-step explanation:
A unique feature of competitive inhibitors is their ability to bind reversibly to the active site of an enzyme, competing with the substrate for that site. Unlike noncompetitive inhibitors which bind at a site other than the active site, competitive inhibitors must structurally resemble the substrate. As such, when competitive inhibitors are present, increasing the substrate concentration can overcome the inhibition and restore enzyme activity. For instance, sulfa drugs act as competitive inhibitors by hindering bacterial folic acid synthesis, thereby blocking bacterial growth.