Calvin cycle occurs in

Options

A. Cytoplasm
B. Chloroplast
C. Mitochondria
D. Glyoxysomes

Answer

**Step-by-Step Solution:**

1. **Understanding the Calvin Cycle**: The Calvin cycle, also known as the Calvin-Benson cycle, is a crucial part of photosynthesis in plants. It is responsible for converting carbon dioxide (CO2) into organic compounds, primarily glucose.

2. **Location of the Calvin Cycle**: The Calvin cycle occurs in the chloroplasts of plant cells. More specifically, it takes place in the stroma, which is the fluid-filled space surrounding the thylakoids in the chloroplasts.

3. **Role of Enzymes**: The process involves various photosynthetic enzymes, with RuBisCO (ribulose bisphosphate carboxylase/oxygenase) being the primary enzyme. This enzyme plays a key role in the fixation of CO2 during the cycle.

4. **Key Processes in the Calvin Cycle**: The Calvin cycle consists of three main stages:
- **Carbon Fixation**: CO2 is fixed into an organic molecule.
- **Reduction Phase**: The fixed carbon is reduced to form carbohydrates.
- **Regeneration of RuBP**: The cycle regenerates ribulose bisphosphate (RuBP) to continue the process.

5. **Conclusion**: Based on the above information, the correct answer to the question "Calvin cycle occurs in" is **chloroplasts**.

**Final Answer**: The Calvin cycle occurs in chloroplasts.

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