Question

List out the differences between xylem and phloem.

Answer 1

The Xylem tissue consists of four types of cells:

1. Tracheids: They are elongated dead cells with tapering ends. Their main function is in upward conduction of water and provide mechanical support.
2. Vessels: They are like tube-like structures placed one above the other forming long channels. They provide mechanical support and also transport water and mineral salts laterally and vertically upward.
3. Fibres: They are long, narrow and tapering at both ends. They provide only mechanical support.
4. Parenchyma: They are living cells and helps in the conduction of water and minerals, and serve for the storage of food.

The Phloem tissue consists of four types of cells:

1. Seive tubes: They are formed of seive cells and form the main conducting part of the phloem. These are cylindrical cells arranged in vertical rows, joined end to end. Their end walls are perforated by pores and are called seive plates. Seive piates helps in passing food material from cell to cell.
2. Companion Cells: They are associated with seive tubes. It help sieve tubes in the conduction of food material.
3. Parenchyma: It is formed of thin-walled unspecialized parenchymatous cells and these cells store food.
4. Phloem fibres: They are dead sclerenchyma fibres formed of elongated cells. These provide mechanical strength.