Select the incorrect statement about functions of Zn in orgainsms:

Options

A. it regulate alcohol dehydrogenase
B. It regulates carbonic anhydrase
C. It help tryptophan synthesis
D. It protects the plant against fungal attack

Answer

To solve the question regarding the incorrect statement about the functions of Zinc (Zn) in organisms, we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Understanding the Role of Zinc in Organisms**:
- Zinc is classified as a micronutrient, which means it is required in small amounts by organisms, particularly plants. It plays a crucial role in various biochemical processes.

2. **Evaluating Each Statement**:
- **Statement 1**: "It regulates alcohol dehydrogenase."
- This statement is **correct**. Zinc is known to be a cofactor for alcohol dehydrogenase, an enzyme involved in the metabolism of alcohol.

- **Statement 2**: "It regulates carbonic anhydrase."
- This statement is also **correct**. Zinc is a component of carbonic anhydrase, which is important for the regulation of pH and carbon dioxide transport in the body.

- **Statement 3**: "It helps tryptophan synthesis."
- This statement is **correct** as well. Zinc plays a role in the synthesis of tryptophan, which is a precursor for the plant hormone auxin.

- **Statement 4**: "It protects the plant against fungal attack."
- This statement is **incorrect**. While Zinc is essential for many physiological functions, it does not directly protect plants from fungal attacks.

3. **Conclusion**:
- The incorrect statement about the functions of Zinc in organisms is **Statement 4**: "It protects the plant against fungal attack."

### Final Answer:
The incorrect statement about functions of Zn in organisms is: **It protects the plant against fungal attack.**

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