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

Options

A. proteins
B. non-proteins
C. tightly bound to enzymes
D. metal compounds.

Answer

To determine which statement about prosthetic groups is false, we need to analyze each of the provided options:

1. **Prosthetic groups are proteins.**
- This statement is false. Prosthetic groups are not proteins; they are non-protein components that are tightly bound to enzymes. They can be essential for the enzyme's activity.

2. **Prosthetic groups are non-proteins.**
- This statement is true. Prosthetic groups are indeed non-protein entities that assist in the function of enzymes.

3. **Prosthetic groups are tightly bound to enzymes.**
- This statement is also true. Prosthetic groups are typically tightly bound to the enzyme, meaning they are not easily removed.

4. **Prosthetic groups are metal compounds.**
- This statement can be true as well. Many prosthetic groups can include metal ions, which are crucial for the activity of certain enzymes.

Based on this analysis, the statement that prosthetic groups are proteins is the false one.

### Final Answer:
The false statement with respect to prosthetic groups is: **Prosthetic groups are proteins.**