According to Lock and Key model, the active site is regarded as:
Correct answer: A. Rigid and specific
- A. Rigid and specific
- B. Flexible and specific
- C. Rigid and non specific
- D. Flexible and non specific
Explanation
Fischer's lock and key model treats the active site as a pre formed rigid shape that only the matching substrate fits, which explains specificity but not the conformational changes later observed. Koshland's induced fit model keeps the specificity but makes the site flexible, moulding itself around the substrate as it binds. Both models agree that the enzyme is specific.
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About Mode of Enzyme Action
Enzyme action depends on the active site forming a temporary enzyme substrate complex, then converting substrate into products with lower activation energy. The lock and key and induced fit models explain specificity and binding, while cofactors and changes in enzyme shape can affect catalysis.
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