In sugarcane plant , which of the following enzymes is responsible for the fixation on of `.^(14)CO_2` in malic acid ?

Options

A. Fructose phosphatase
B. Ribulose bisphosphate carboxylase
C. Phosphoenol pyruvic acid carboxylase
D. Ribulose phosphate kinase

Answer

To solve the question regarding which enzyme is responsible for the fixation of \(^{14}CO_2\) in malic acid in sugarcane plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- The question pertains to the fixation of carbon dioxide in malic acid, which is a part of the C4 photosynthetic pathway. This pathway is characteristic of certain plants, including sugarcane.

2. **Identifying the Enzyme**:
- In C4 plants, the initial fixation of carbon dioxide occurs in the mesophyll cells. The enzyme responsible for this process is crucial to identify.

3. **Enzyme Function**:
- The enzyme that catalyzes the fixation of carbon dioxide into a four-carbon compound (malic acid) is known as phosphoenolpyruvate carboxylase (PEP carboxylase).

4. **Formation of Malic Acid**:
- PEP carboxylase catalyzes the reaction where phosphoenolpyruvate (PEP) combines with carbon dioxide to form oxaloacetate, which is then converted to malic acid.

5. **Conclusion**:
- Based on the above understanding, the correct enzyme responsible for the fixation of \(^{14}CO_2\) in malic acid in sugarcane is phosphoenolpyruvate carboxylase (PEP carboxylase).

### Final Answer:
- The enzyme responsible for the fixation of \(^{14}CO_2\) in malic acid in sugarcane is **phosphoenolpyruvate carboxylase (PEP carboxylase)**.

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