Why does the rate of an enzyme reaction level off at high substrate concentration?
Answer and explanation
Correct answer: C. All the active sites are occupied
- Step 1: At low concentration, rate rises as more collisions occur. Step 2. At saturation every active site is working at maximum turnover. Answer: All the active sites are occupied. Why not the others: substrate does not denature enzymes; product inhibition would reduce, not just level, the rate; activation energy does not depend on concentration.
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