When `CO_(2)` is added to PEP. The first stabel product synthesised is

Options

A. Pyruvate
B. glyceradehyde-3-phosphate
C. phosphoglycerate
D. oxalocetate.

Explanation

To solve the question "When CO₂ is added to PEP, the first stable product synthesized is:", we can follow these steps:

### Step-by-Step Solution:

1. **Identify PEP**:
- PEP stands for phosphoenolpyruvate, which is a 3-carbon compound and acts as a primary CO₂ acceptor in certain plants.

2. **Understand the Context**:
- This reaction primarily occurs in C4 plants (also referred to as Kranz anatomy plants), where the initial fixation of CO₂ takes place.

3. **Identify the Enzyme**:
- The enzyme responsible for the carboxylation of PEP is called PEP carboxylase (or PEPcase). This enzyme catalyzes the reaction between CO₂ and PEP.

4. **Reaction Process**:
- When CO₂ is added to PEP, the PEP combines with CO₂ in the presence of PEP carboxylase.

5. **Determine the Product**:
- The first stable product formed from this reaction is oxaloacetic acid (also known as oxaloacetate), which is a 4-carbon compound.

6. **Conclusion**:
- Therefore, the answer to the question is that the first stable product synthesized when CO₂ is added to PEP is **oxaloacetate**.

### Final Answer:
The first stable product synthesized when CO₂ is added to PEP is **oxaloacetate**.

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