Which of the following is the first compound that accepts carbon dioxide during dark phase of photosynthesis?

Options

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

Answer

To answer the question, "Which of the following is the first compound that accepts carbon dioxide 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. It is the stage where carbon dioxide is fixed into organic molecules.

2. **Identify the Reactants**: In the Calvin Cycle, carbon dioxide from the atmosphere is utilized. The process begins with the combination of carbon dioxide and a five-carbon compound.

3. **Identify the Key Compound**: The five-carbon compound that plays a crucial role in the Calvin Cycle is Ribulose-1,5-bisphosphate (RUBP).

4. **Enzyme Involvement**: The enzyme responsible for catalyzing the reaction between carbon dioxide and RUBP is called Ribulose-1,5-bisphosphate carboxylase/oxygenase (commonly known as Rubisco).

5. **Conclusion**: The first compound that accepts carbon dioxide during the dark phase of photosynthesis is Ribulose-1,5-bisphosphate (RUBP).

### Final Answer:
The first compound that accepts carbon dioxide during the dark phase of photosynthesis is **Ribulose-1,5-bisphosphate (RUBP)**.

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