Biology · Enzymes
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The number of models that represent the enzyme-substrate model are?
- A
1
- B
2
- C
3
- D
4
There are two main models that represent the enzyme-substrate interaction:
Lock-and-Key Model
Induced Fit Model
Some students may think that there is only one model to explain enzyme–substrate interaction. This idea usually comes from learning only the lock-and-key concept in earlier studies. However, this is incorrect because research has shown that more than one model exists to explain how enzymes and substrates interact.
The correct answer is two models. These are the Lock-and-Key Model and the Induced Fit Model. The lock-and-key model, proposed by Emil Fischer in 1894, describes the active site as rigid and specifically shaped to match the substrate. Later, in 1959, Daniel Koshland proposed the induced fit model, which explained that enzymes are flexible, and their active site changes shape slightly to perfectly fit the substrate.
Suggesting three models is incorrect. Some learners may confuse other enzyme-related concepts, like the transition state theory or enzyme inhibition mechanisms, with models of enzyme-substrate interaction. However, these are not considered separate models of enzyme binding, so three is not the correct number.
This option is also wrong because no biological or biochemical reference supports the existence of four different enzyme–substrate models. Standard textbooks and scientific explanations only describe two well-accepted models, not four.
Tagged under Biology · Enzymes · 2021