Question

Assertion (A) Enzymes have active sites that hold substrate molecule for a chemical reaction.
Reason (R) Drugs compete with natural substrate by attaching covalently to the active site of enzyme.

• A. Both $A$ and $R$ are correct; $R$ is the correct explanation of $A$.
• B. Both $A$ and $R$ are correct; $R$ is not the correct explanation of $A$.
• C. $A$ is correct; $R$ is incorrect.
• D. $R$ is correct; $A$ is incorrect.

Answer 1

Answer: (C)

Enzyme hold the substrate for a chemical reaction. Active sites of enzymes hold the substrate molecule in a suitable position, so that it can be attacked by the reagent effectively. Substrates then bind to the active site of the enzyme through a variety of interactions such as ionic bond, hydrogen bonding, van der Waals' interaction.