Select the incorrect statement form the following.

Options

A. Active enzyme has tertiary structure having many active sites (substrate binding sites).
B. Enzymes are biocatalyst.
C. Enzymes are highly specific.
D. Enzymes are mainly protein in nature.

Answer

To solve the question of identifying the incorrect statement about enzymes, we will analyze each statement provided in the options.

### Step-by-Step Solution:

1. **Understanding the Structure of Enzymes**:
- Enzymes are proteins that have a specific three-dimensional structure, which is crucial for their function. This structure is often described in terms of primary, secondary, tertiary, and quaternary levels.
- The tertiary structure is the overall shape of the enzyme, which is formed by the folding of the polypeptide chain.

**Hint**: Remember that the tertiary structure is essential for enzyme functionality.

2. **Evaluating the First Statement**:
- The first statement claims that "active enzyme has tertiary structure having many active sites."
- While it is true that enzymes have a tertiary structure, the claim about having "many active sites" is misleading. Typically, an enzyme has one or two active sites that are specific for their substrates.

**Hint**: Consider how many active sites are usually present in a typical enzyme.

3. **Evaluating the Second Statement**:
- The second statement is "enzymes are biocatalysts."
- This statement is correct. Enzymes indeed act as biocatalysts, speeding up biochemical reactions without being consumed in the process.

**Hint**: Recall the definition of biocatalysts.

4. **Evaluating the Third Statement**:
- The third statement is "enzymes are highly specific."
- This statement is also correct. Enzymes are specific to their substrates, meaning that each enzyme typically catalyzes only one type of reaction or acts on a specific substrate.

**Hint**: Think about the specificity of enzymes and how they relate to their substrates.

5. **Evaluating the Fourth Statement**:
- The fourth statement is "enzymes are mainly protein in nature."
- This statement is correct as well. Most enzymes are proteins, although some RNA molecules can also have catalytic activity (ribozymes).

**Hint**: Consider the composition of enzymes and their classification.

6. **Conclusion**:
- After evaluating all the statements, the only incorrect statement is the first one: "active enzyme has tertiary structure having many active sites." Enzymes typically have one or two active sites, not many.

### Final Answer:
The incorrect statement is: **"active enzyme has tertiary structure having many active sites."**