Which of the following statements best explains the name of the 'induced fit model' in enzyme-substrate interactions?

• A. The enzyme and substrate have perfectly complementary shapes before binding.
• B. The substrate is forced to fit into the rigid active site of the enzyme.
• C. The enzyme changes its shape to better accommodate the substrate upon binding.
• D. The enzyme permanently alters its structure after binding the substrate.

Answer: (C)

Verified step by step guidance

1. Understand the concept of the 'induced fit model' in enzyme-substrate interactions. This model describes how enzymes are flexible and can change their shape to better accommodate the substrate upon binding.
2. Compare the given statements to the induced fit model. The first statement, 'The enzyme and substrate have perfectly complementary shapes before binding,' aligns with the older 'lock and key model,' not the induced fit model.
3. Evaluate the second statement, 'The substrate is forced to fit into the rigid active site of the enzyme.' This is incorrect because the induced fit model emphasizes enzyme flexibility, not rigidity.
4. Analyze the third statement, 'The enzyme changes its shape to better accommodate the substrate upon binding.' This aligns with the induced fit model, as it highlights the enzyme's ability to adapt its shape for optimal interaction with the substrate.
5. Review the fourth statement, 'The enzyme permanently alters its structure after binding the substrate.' This is incorrect because the induced fit model involves temporary changes in enzyme shape, which revert after the reaction is complete.