Concept:The defining clinical feature of competitive inhibition is that it can be overcome by flooding the system with excess natural substrate.
Solution:- The toxic compound 'A' was blocking the active sites of a vital enzyme.
- By injecting a massive dose of normal substrate 'B', the doctors drastically shifted the concentration ratio.
- The abundant substrate 'B' out-competed the toxic inhibitor 'A' for the active sites, allowing the enzyme to resume its life-saving function.
- This proves the toxin formed weak bonds and fought for the active site, meaning it was a competitive reversible inhibitor.
Why other options are incorrect:If it were irreversible, the enzyme would be permanently dead, and adding substrate would do nothing. If it were non-competitive, it would be bound elsewhere changing the active site shape, and flooding substrate into a broken active site would also fail.
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