The following is not relate to `C_4` plant
Water use efficiency is more
Photorespiration is not detectable
`CO_2` compensation points is high
The primary acceptor of `CO_2` is a 3C compound

Options

A. Water use efficiency is more
B. Photorespiration is not detectable
C. `CO_2` compensation points is high
D. The primary acceptor of `CO_2` is a 3C compound

Answer

To determine which statement is not related to C4 plants, we can analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding C4 Plants**:
- C4 plants have a unique leaf anatomy known as Kranz anatomy, which allows them to efficiently carry out photosynthesis in hot and dry environments.

2. **Analyzing Water Use Efficiency**:
- C4 plants are known for having a higher water use efficiency compared to C3 plants. This is because they can fix CO2 more efficiently and minimize water loss through transpiration.
- **Conclusion**: This statement is true for C4 plants.

3. **Photorespiration**:
- In C4 plants, photorespiration is minimized or not detectable because they have a mechanism that concentrates CO2 around the enzyme RuBisCO, reducing the chances of it fixing oxygen instead of carbon dioxide.
- **Conclusion**: This statement is also true for C4 plants.

4. **CO2 Compensation Point**:
- C4 plants typically have a low CO2 compensation point, meaning they can continue photosynthesis even at low concentrations of CO2. This is due to the high affinity of the enzyme phosphoenolpyruvate carboxylase (PEP carboxylase) for CO2.
- **Conclusion**: The statement that the CO2 compensation point is high is incorrect for C4 plants.

5. **Primary Acceptor of CO2**:
- In C4 plants, the primary acceptor of CO2 is phosphoenolpyruvic acid (PEP), which is a 3-carbon compound. This is a defining characteristic of C4 photosynthesis.
- **Conclusion**: This statement is true for C4 plants.

### Final Answer:
The statement that is **not related** to C4 plants is: **"CO2 compensation point is high."**

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