A competitive inhibitor reduces enzyme activity. Why can the effect be reduced by adding more substrate?
Answer and explanation
Correct answer: D. Inhibitor and substrate share the active site
- Step 1: A competitive inhibitor has a shape similar to the substrate.
- Step 2: Higher substrate concentration makes it more likely that substrate occupies the active site.
Answer
Inhibitor and substrate share the active site.
Why not the others: The substrate changes the shape of the inhibitor as it binds: the inhibitor's shape is not altered. The inhibitor binds elsewhere on the enzyme and is released when substrate rises: this describes non-competitive inhibition. The extra substrate destroys the inhibitor molecules: the inhibitor is not destroyed.
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