Phloem fibres (bast fibres) are made up of________ cells :

Options

A. Parenchymatous
B. Sclerenchymatous
C. Companion
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Phloem Fibres**: Phloem fibres, also known as bast fibres, are specialized structures found in the phloem tissue of plants. They play an essential role in providing mechanical support.

2. **Identifying Cell Types**: The question asks about the type of cells that make up phloem fibres. The options provided are:
- Parenchymatous cells
- Sclerenchymatous cells
- Companion cells
- All of these

3. **Analyzing Each Option**:
- **Parenchymatous Cells**: These are living cells that are typically involved in storage and metabolic functions. They do not provide the mechanical support needed for phloem fibres.
- **Sclerenchymatous Cells**: These are dead cells that provide structural support due to their thickened cell walls. They are indeed the cells that make up phloem fibres.
- **Companion Cells**: These are specialized parenchyma cells that assist in the functioning of sieve tube elements in the phloem. They do not form phloem fibres.
- **All of These**: This option implies that all the mentioned cell types contribute to phloem fibres, which is incorrect.

4. **Conclusion**: Based on the analysis, phloem fibres (bast fibres) are made up of sclerenchymatous cells.

**Final Answer**: Sclerenchymatous cells.

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