Bast fibres are mostly found in -

Options

A. Secondary xylem
B. Secondary phloem
C. Primary phloem
D. Primary xylem

Answer

**Step-by-Step Solution:**

1. **Understanding Bast Fibres**: Bast fibres are known as phloem fibres. They are derived from the phloem tissue of plants.

2. **Identifying the Source**: These fibres are primarily obtained from the stems of dicotyledonous plants. Common sources include cultivated plants like flax and hemp, as well as wild plants like linen and mulberry.

3. **Composition of Bast Fibres**: Bast fibres are composed of sclerenchyma cells, which are rich in cellulose. These cells provide strength and support to the plant.

4. **Analyzing the Options**:
- **Secondary Xylem**: This is primarily involved in water transport and does not contain bast fibres.
- **Secondary Phloem**: This is the correct option as it contains bast fibres.
- **Primary Phloem**: Bast fibres are absent in primary phloem.
- **Primary Xylem**: Similar to secondary xylem, it does not contain bast fibres.

5. **Conclusion**: Based on the analysis, bast fibres are mostly found in secondary phloem.

**Final Answer**: Bast fibres are mostly found in **secondary phloem**.

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