The first compound that accepts `CO_(2)` during dark phase

Options

A. NADP
B. ferrodoxin
C. RuBP
D. cytochrome

Answer

To solve the question regarding the first compound that accepts CO2 during the dark phase of photosynthesis, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Dark Phase of Photosynthesis**:
- The dark phase of photosynthesis is also known as the Calvin cycle. This phase does not require light directly but relies on the products of the light-dependent reactions.

2. **Identify the Process**:
- In the Calvin cycle, the primary process involves the fixation of carbon dioxide (CO2) into organic molecules.

3. **Recognize the First Compound**:
- The first compound that CO2 combines with during the Calvin cycle is ribulose 1,5-bisphosphate (RUBP).

4. **Role of Enzyme**:
- The enzyme that facilitates this reaction is called ribulose 1,5-bisphosphate carboxylase/oxygenase (commonly referred to as RuBisCO).

5. **Conclusion**:
- Therefore, the first compound that accepts CO2 during the dark phase of photosynthesis is RUBP (ribulose 1,5-bisphosphate).

### Final Answer:
The first compound that accepts CO2 during the dark phase is **RUBP (ribulose 1,5-bisphosphate)**.

---