What is the function of xylem?

Answer 1

Functions of xylem:

1. Conductive tissue: moving water from the roots through the stems to the leaves. Water is provided for metabolic functions as well as photosysnethesis
2. Provides/ assists in support of the stems and leaves

Types of Xylem:

It is a complex permanent tissue, which is specialized for the conduction of water and mineral substances in the plant body. Xylem is a heterogenous tissue made up of four different types of cellular elements. They are:

• Xylem tracheids

• Xylem tracheae

• Xylem fibers and

• Xylem parenchyma

Of these, the tracheids and the tracheae are described as essential elements since they are directly involved in the translocation of water and mineral substances. Xylem fibers and xylem parenchyma are described as associated elements, since they are only supporting structures. The tracheids, the trachea and the xylem fibers are non-living components, while xylem parenchyma represents the only living component of the tissue.

Xylem is commonly described as a dead, complex permanent tissue.
The purpose of the xylem is to transport water from root to leaves through stem . Most of the water is moved up the xylem through a process called transpiration pull.

According to the cohesion-tension model, as water evaporates from the stomata in a process called transpiration, water from the xylem moves up into the leaf because of a difference in water potential. The strong hydrogen bonds between the cohesive water molecules "link" the water molecules as they are pulled up through the xylem.

The xylem will perform its job better under certain conditions than others. The factors that affect transpiration rate are temperature, light, and humidity. Lower temperature causes transpiration rate to increase, which allows water to flow through the xylem faster. More light also causes transpiration rate to increase. On the other hand, more humidity causes the transpiration rate to decrease, so water flows slower through the xylem to reach the leaves.

It causes elongation of stem (high concentration) and root (low concentration). It promotes root initiation in cuttings and callus. (Callus is an undifferentiated mass of cells from which the entire plant body can be grown by tissue culture techniques.) It also promotes root development.Tissues made up of elongated, liquefied tubes called vessels and tracheids that conduct water and mineral salts from the roots to the leaves in plants.