Choose incorrect statement w.r.t mesophyll cells of`C_4`-plants

Options

A. Lack of RuBisCO enzyme
B. `C_4`-acid is broken down to release `CO_2` amd a 3-carbon molecule
C. Primary `CO_2` acceptor molecule is PEP
D. Have a PEP case enzyme

Answer

To solve the question of identifying the incorrect statement regarding mesophyll cells of C4 plants, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Understanding Mesophyll Cells in C4 Plants**:
- C4 plants have a unique photosynthetic pathway that involves two types of cells: mesophyll cells and bundle sheath cells. The mesophyll cells are responsible for the initial fixation of carbon dioxide.

2. **Analyzing the Statements**:
- **Statement 1**: "Lack of rubisco enzyme."
- **Analysis**: This statement is **correct**. Mesophyll cells in C4 plants do not contain the enzyme ribulose bisphosphate carboxylase/oxygenase (rubisco). Instead, rubisco is found in the bundle sheath cells where the Calvin cycle occurs.

- **Statement 2**: "C4 acid is broken down to release carbon dioxide in a 3 carbon molecule."
- **Analysis**: This statement is **incorrect**. The breakdown of C4 acids (like malic acid) occurs in the bundle sheath cells, not in the mesophyll cells. The C4 pathway involves the conversion of CO2 into a four-carbon compound, which is then transported to the bundle sheath cells for further processing.

- **Statement 3**: "Primary CO2 acceptor molecule is PEP."
- **Analysis**: This statement is **correct**. In mesophyll cells of C4 plants, phosphoenolpyruvate (PEP) acts as the primary CO2 acceptor, which is crucial for the C4 pathway.

- **Statement 4**: "Have a PEP case enzyme."
- **Analysis**: This statement is **correct**. Mesophyll cells contain the enzyme PEP carboxylase (PEPC), which catalyzes the fixation of CO2 to PEP to form oxaloacetate.

3. **Conclusion**:
- The incorrect statement regarding mesophyll cells of C4 plants is **Statement 2**: "C4 acid is broken down to release carbon dioxide in a 3 carbon molecule."

### Final Answer:
The incorrect statement is **Option 2**.