Question

What xylem means?

Answer 1

Xylem:

1. It is a type of complex tissue present in plants, that primarily transports water & nutrients from roots to stem and the leaves.
2. They are responsible for providing mechanical strength to plants.
3. Xylem is composed of four different kinds of elements: Tracheids, Vessels, Xylem Fibers, and Xylem Fibers.

Tracheids:

1. These are dead, tube-like cells with a tapering end.
2. They are present mostly in the gymnosperm and the lower angiosperm.
3. They also have a thick lignified wall & lack protoplasm.
4. Their main function is the transportation of water and mineral.

Vessels:

1. These are long tube-like cylindrical structures.
2. The walls are also lignified and usually have a large central cavity. lacking protoplasm.
3. They usually have many cells called vessel members that are interconnected by a perforation in common walls.
4. They are primarily involved in the conduction of water, and minerals & give mechanical strength to the plant.

Xylem Fibers:

These are dead cells with the lignified walls & a central lumen involved in water transportation and providing mechanical support.

Xylem Parenchyma:

These are living thin-walled cells that help in storing food in form of starch or fat.

On basis of origin, there are two types of xylem cells:

1. Primary xylem: It originates from the procambium, further divided into the protoxylem & metaxylem
2. Secondary xylem: It originates from the vascular cambium