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 selecting the incorrect statement, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Examine Option 1:**
- The statement claims that "the active enzyme has a tertiary structure having many substrate binding sites."
- **Analysis:**
- Enzymes do have a tertiary structure, which is crucial for their function.
- However, typically, an active enzyme has one specific substrate binding site (the active site) where the substrate binds.
- Therefore, this statement is incorrect because it suggests that there are many substrate binding sites.

2. **Examine Option 2:**
- The statement claims that "Enzymes are biocatalysts."
- **Analysis:**
- This statement is correct. Enzymes are indeed biocatalysts that speed up chemical reactions in biological systems without being consumed in the process.

3. **Examine Option 3:**
- The statement claims that "Enzymes lower the activation energy of the reaction."
- **Analysis:**
- This statement is also correct. One of the primary functions of enzymes is to lower the activation energy required for reactions, thus facilitating them.

4. **Examine Option 4:**
- The statement claims that "Enzymes are mainly proteinaceous in nature."
- **Analysis:**
- This statement is correct as well. Most enzymes are proteins, although there are some RNA molecules that also have catalytic activity (ribozymes), but the majority are indeed proteinaceous.

### Conclusion:
After analyzing all options, we find that the incorrect statement is **Option 1**: "the active enzyme has a tertiary structure having many substrate binding sites."