Meristematic cells are characterised by

Options

A. thin cellulosic cell walls
B. dense protoplasm
C. prominent nuclei
D. all of these

Explanation

**Step-by-Step Solution:**

1. **Definition of Meristematic Cells**:
- Meristematic cells are undifferentiated cells in plants that have the ability to divide continuously. They are responsible for the growth of plants.

2. **Characteristics of Meristematic Cells**:
- **Thin Cell Walls**: Meristematic cells have thin cell walls made of cellulose. This allows them to expand and divide easily. Thick or secondary cell walls would hinder their ability to grow and divide.
- **Dense Protoplasm**: These cells contain dense protoplasm, which indicates high metabolic activity. This density is essential for the active division and growth of these cells.
- **Prominent Nucleus**: Meristematic cells have a prominent nucleus, which is crucial for the regulation of cell division and metabolic activities.

3. **Comparison with Permanent Cells**:
- As meristematic cells differentiate into permanent tissues, they undergo changes such as thickening of cell walls and loss of protoplasm and nucleus. Permanent cells typically have thick secondary walls and may lose their nucleus and cytoplasm.

4. **Conclusion**:
- Given the characteristics discussed, meristematic cells are characterized by having thin cell walls, dense protoplasm, and a prominent nucleus. Therefore, the correct answer to the question is that meristematic cells are characterized by all of these features.

**Final Answer**: Meristematic cells are characterized by all of these features (thin cell walls, dense protoplasm, and prominent nucleus).

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