Select the incorrect statement from the following.

Options

A. The active enzyme has a tertiary structure having many substrate binding sites.
B. Enzymes are biocatalyst.
C. Enzymes lowers the activation energy of the reaction.
D. Enzymes are mainly protein in nature.

Answer

To solve the question of identifying the incorrect statement regarding enzymes, we will analyze each provided statement one by one.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "Active enzyme as a tertiary structure have many substrate binding sites."
- **Analysis**: Enzymes do have a tertiary structure, which is crucial for their function. However, they typically have a limited number of active sites (usually one or two) for substrate binding, not "many." Therefore, this statement is incorrect.

2. **Statement 2**: "Enzymes are biocatalysts."
- **Analysis**: This statement is true. Enzymes are biological catalysts that speed up chemical reactions in living organisms.

3. **Statement 3**: "Enzymes lower the activation energy of the reaction."
- **Analysis**: This statement is also true. Enzymes work by lowering the activation energy required for a reaction to occur, facilitating the conversion of substrates into products.

4. **Statement 4**: "Enzymes are mainly protein in nature."
- **Analysis**: This statement is true as well. Most enzymes are proteins, although some RNA molecules can also have catalytic activity (ribozymes), but the majority are indeed proteinaceous.

5. **Conclusion**:
- The only incorrect statement among the options is the first one: "Active enzyme as a tertiary structure have many substrate binding sites."

### Final Answer:
The incorrect statement is: **"Active enzyme as a tertiary structure have many substrate binding sites."**

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