All enzymes incorporate

Options

A. active site
B. coenzyme
C. metal ion
D. all of these

Explanation

To answer the question "All enzymes incorporate," we need to analyze the options provided and understand the role of enzymes in biochemical reactions.

### Step-by-Step Solution:

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up biochemical reactions. They are crucial for various metabolic processes in living organisms.

2. **Identifying the Components of Enzymes**: Enzymes have specific components that are essential for their function. Some of these components include:
- **Active Site**: This is the region on the enzyme where the substrate binds. The active site is crucial for the enzyme's catalytic activity.
- **Coenzymes**: These are organic molecules that assist enzymes in catalyzing reactions. They are not present in all enzymes.
- **Metal Ions**: Some enzymes require metal ions as cofactors to function properly, but again, not all enzymes incorporate metal ions.

3. **Evaluating the Options**:
- **Active Site**: All enzymes have an active site where substrates bind.
- **Coenzyme**: Not all enzymes require coenzymes.
- **Metal Ion**: Not all enzymes require metal ions.
- **All of These**: This option implies that all enzymes incorporate active sites, coenzymes, and metal ions, which is incorrect.

4. **Conclusion**: Since all enzymes must have an active site for substrate binding and catalysis, the correct answer to the question "All enzymes incorporate" is **Active Site**.

### Final Answer:
All enzymes incorporate **Active Site**.

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