Question
Describe components of phloem. Define translocation.
✓
Answer
Phloem is made up of four types of elements: Sieve tubes, companion cells, phloem fibres and the phloem parenchyma.
- Sieve tubes: These are tubular cells with perforated walls. These cells are responsible for transportation of food and nutrients.
- Companion cells: These cells are found associated with sieve tubes and connected with it by simple pits. These cells are long, narrow and thin walled. These cells are living.
- Phloem fibres: They have thick cell wall and they provide mechanical support to plant.
- Pholem parenchyma: These cells are living and often cylindrical in shape.
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