Phloem fibre are made up of (A)____cells. These are generally absent in the (B)_____

Answer

To answer the question about phloem fibers, we can break it down into the following steps:

1. **Understanding Phloem**: Phloem is a type of vascular tissue in plants responsible for the transport of organic nutrients, particularly sugars produced through photosynthesis.

2. **Components of Phloem**: Phloem is composed of several specialized cells, including:
- Sieve elements
- Companion cells
- Phloem fibers
- Phloem parenchyma cells

3. **Identifying Phloem Fibers**: Phloem fibers, also known as bast fibers, are a specific type of cell found within the phloem.

4. **Cell Type of Phloem Fibers**: Phloem fibers are made up of sclerenchyma cells. Sclerenchyma cells are known for their thick, lignified walls and provide structural support to the plant.

5. **Location of Phloem Fibers**: Phloem fibers are generally absent in primary phloem, which is the first type of phloem formed during the growth of the plant. They are more commonly found in secondary phloem, which develops later as the plant matures.

6. **Final Answers**:
- (A) Phloem fibers are made up of **sclerenchyma cells**.
- (B) Phloem fibers are generally absent in the **primary phloem**.