In CAM plants, CO2 acceptor is

Options

A. RuBP
B. PEP
C. OAA
D. PGA

Answer

**Step-by-Step Solution:**

1. **Understanding CAM Plants**: CAM stands for Crassulacean Acid Metabolism. These plants have a unique way of photosynthesis that allows them to conserve water in arid conditions.

2. **Carbon Fixation Timing**: In CAM plants, carbon fixation occurs at two different times: at night and during the day.

3. **Nighttime Carbon Fixation**: During the night, CAM plants fix carbon dioxide. The CO2 acceptor used at this time is phosphoenolpyruvate (PEP).

4. **Daytime Carbon Fixation**: During the daytime, the carbon dioxide fixation process utilizes ribulose bisphosphate (RuBP) as the CO2 acceptor, which is facilitated by the enzyme Rubisco.

5. **First Stable Product**: The first stable product formed during the nighttime fixation is oxaloacetic acid.

6. **Conclusion**: Therefore, the CO2 acceptor in CAM plants during nighttime is phosphoenolpyruvate (PEP).

**Final Answer**: The CO2 acceptor in CAM plants is phosphoenolpyruvate (PEP).

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