Question

Statements about Enzyme Inhibitor Drugs are given below:

1. There are Competitive and Noncompetitive inhibitor drugs
2.  These can bind at the active sites and allosteric sites
3.  Competitive Drugs are allosteric site blocking drugs
4.  Non-competitive Drugs are active site blocking drugs 

Choose the correct answer from the options given below :

• A. (A), (D) only
• B. ( A ),( C ) only
• C. (A), (B) only
• D. ( A ),( B ),( C ) only

Answer 1

The Correct Option is C

Let us analyze each statement about enzyme inhibitor drugs:

1. There are Competitive and Noncompetitive inhibitor drugs.

This statement is correct. Enzyme inhibitors are commonly classified into competitive and noncompetitive inhibitors based on how they interact with enzymes.

2. These can bind at the active sites and allosteric sites.

This statement is correct. Inhibitors can bind to the active site or different sites called allosteric sites. Competitive inhibitors typically bind to the active site, while noncompetitive inhibitors bind to allosteric sites or other parts of the enzyme.

3. Competitive Drugs are allosteric site blocking drugs.

This statement is incorrect. Competitive inhibitors resemble the substrate and bind to the enzyme's active site to block substrate binding, not the allosteric site.

4. Non-competitive Drugs are active site blocking drugs.

This statement is also incorrect. Noncompetitive inhibitors typically bind to an enzyme at a site other than the active site and do not block substrate binding directly. Instead, they inhibit enzyme activity by altering the enzyme's shape or function.

Based on this analysis, the correct statements are (A) and (B) only, making the correct answer:

(A), (B) only

By understanding the mechanisms of inhibition, we see that competitive inhibitors occupy the active site while noncompetitive inhibitors act elsewhere, altering enzyme activity.