Biology Enzymes MDCAT 2019
PMDC Verified Question 65 of 79
What is common in both competitive and non-competitive inhibition?
A
Non-Reversible inhibition
B
Reversible inhibition
C
Feedback inhibition
D
Irreversible inhibition
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: Reversible inhibition
Concept:

Enzyme inhibitors are broadly classified into two main categories based on whether their effects are permanent (covalent) or temporary (weak bonds).

Solution:

  • Both competitive (blocking the active site) and non-competitive (binding to an allosteric site) inhibitors are primary examples of reversible inhibition.
  • They attach to the enzyme using weak, non-covalent interactions (like hydrogen or ionic bonds).
  • Because these bonds are weak, the inhibitor can eventually detach, allowing the enzyme to regain its full catalytic function.


Why other options are incorrect:

Irreversible/non-reversible inhibition involves permanent destruction of the enzyme via strong covalent bonds (like poisons or heavy metals). Feedback inhibition is a specific metabolic pathway mechanism, not a structural classification shared universally by all competitive/non-competitive inhibitors.

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