Which of the following is false with respect to prosthetic groups ?

Options

A. Proteins
B. Non - proteins
C. metal compounds
D. Tightly bound to enzymes

Answer

To determine which statement is false with respect to prosthetic groups, we need to analyze the characteristics of prosthetic groups in relation to the options provided.

### Step-by-Step Solution:

1. **Understanding Prosthetic Groups**:
Prosthetic groups are non-polypeptide units that are tightly and permanently attached to enzymes. They play a crucial role in the enzyme's activity.

2. **Identifying the Options**:
We have four options to consider:
- A) Proteins
- B) Non-proteins
- C) Metal compounds
- D) Tightly bound to enzymes

3. **Analyzing Each Option**:
- **Option A: Proteins**: Prosthetic groups are not proteins; they are typically non-protein molecules. This statement is false.
- **Option B: Non-proteins**: This is true as prosthetic groups are indeed non-protein entities.
- **Option C: Metal compounds**: This is also true; prosthetic groups can include metal ions (like iron in hemoglobin).
- **Option D: Tightly bound to enzymes**: This is true; prosthetic groups are characterized by their tight binding to enzymes.

4. **Conclusion**:
Based on the analysis, the only false statement regarding prosthetic groups is that they are proteins. Therefore, the correct answer is **Option A: Proteins**.

### Final Answer:
The false statement with respect to prosthetic groups is **Option A: Proteins**.

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