Which one is correct?

Options

A. Cofactor plays crucial role in catalytic activity of the enzymes
B. Zn is activator of carboxypeptidase
C. Catalase and peroxidase have haem as prosthetic group
D. All

Answer

To determine which statement is correct regarding enzymes and their cofactors, let's analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Cofactors**:
- Cofactors are non-protein components that assist enzymes in their catalytic activity. They can be metal ions or organic molecules.
- **Conclusion**: Option 1 states that cofactors play a crucial role in the catalytic activity of enzymes, which is true.

2. **Analyzing Zinc as a Cofactor**:
- Zinc is known to act as a cofactor for various enzymes, including carboxypeptidase. It enhances the enzyme's catalytic activity.
- **Conclusion**: Option 2 claims that zinc is an activator of carboxypeptidase, which is correct.

3. **Examining Catalases and Peroxidases**:
- Catalases and peroxidases are enzymes that contain a heme group, which is a type of prosthetic group. This heme group is essential for their function and is tightly bound to the enzyme.
- **Conclusion**: Option 3 states that catalases and peroxidases have a heme prosthetic group, which is also true.

4. **Final Evaluation**:
- Since all three options (1, 2, and 3) are correct, the answer to the question is that all options are correct.
- **Conclusion**: Therefore, option 4, which states that all of the above are correct, is the right answer.

### Final Answer:
The correct answer is option 4: All of the above.

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