Which one of the following is surrounded by a callose wall

Options

A. Egg
B. Pollen grain
C. Microspore mother cell
D. Male gamate

Answer

To answer the question "Which one of the following is surrounded by a callose wall?" we will analyze the options provided: egg, pollen grain, microspore mother cell, and male gamete.

### Step-by-Step Solution:

1. **Understanding Callose**:
- Callose is a plant polysaccharide that plays a crucial role in the structure of plant cells. It is known for its function in forming walls around certain types of cells.

2. **Identifying the Options**:
- **Egg**: The female gamete in plants, generally does not have a callose wall.
- **Pollen Grain**: This is the male gametophyte that develops from the microspore but is not surrounded by a callose wall.
- **Microspore Mother Cell**: This is a diploid cell that undergoes meiosis to produce haploid pollen grains. It is during the initiation of meiosis that callose is deposited on its cell wall.
- **Male Gamete**: The male gamete itself does not have a callose wall.

3. **Analyzing the Microspore Mother Cell**:
- The microspore mother cell is specifically surrounded by a callose wall at the initiation of meiosis. This callose layer acts as an isolation barrier, separating one microspore mother cell from another.

4. **Conclusion**:
- Based on the analysis, the correct answer is the **Microspore Mother Cell**, as it is the only option that is surrounded by a callose wall.

### Final Answer:
**Microspore Mother Cell (Option C)**

---