Structure associated with chloroplast of green algae is

Options

A. Pyrenoid
B. Stigma
C. Both A and B
D. Endoplasmic reticulum

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the structure associated with the chloroplast of green algae. We need to identify the correct option from the given choices.

2. **Analyzing the Options**:
- **Option A: Pyrenoid**: Pyrenoids are micro compartments found within the chloroplasts of green algae. They are known for containing the enzyme Rubisco, which is crucial for carbon fixation during photosynthesis.
- **Option B: Stigma**: The stigma, also known as the eyespot apparatus, is a photoreceptive organelle found in some green algae. It helps the organism detect light intensity and direction, aiding in optimizing conditions for photosynthesis.
- **Option C: Both A and B**: This option suggests that both pyrenoid and stigma are associated with the chloroplasts of green algae.
- **Option D: Endoplasmic Reticulum**: The endoplasmic reticulum is not specifically associated with the chloroplasts of green algae.

3. **Identifying the Correct Structures**:
- Pyrenoids are indeed associated with chloroplasts in green algae and play a role in carbon fixation and starch storage.
- Stigmas are also associated with chloroplasts in green algae, particularly in motile cells, and help in detecting light for photosynthesis.

4. **Conclusion**: Since both pyrenoid and stigma are associated with the chloroplasts of green algae, the correct answer is **Option C: Both A and B**.

**Final Answer**: The structure associated with chloroplast of green algae is **both A (Pyrenoid) and B (Stigma)**.

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