Question

In which direction does the water moves in xylem?

Answer 1

Xylem:

Xylem is a complex tissue responsible for the transport of water and minerals throughout the plant. It is made up of four components which include tracheids, vessels, xylem parenchyma, and xylem fibres.

Transport by xylem:

1. The direction of xylem transport is upwards and unidirectional i.e. from roots to other plant parts.
2. The water column moves only upwards because of the two forces, transpirational pull, and positive root pressure.
3. The transpirational pull is a force generated due to the loss of water from the aerial parts of the plants in the form of water vapor. It creates negative pressure.
4. Whereas, the root pressure is a positive hydrostatic pressure that sends water upwards from the roots towards the shoot region.
5. Hence, xylem transport is upwards and unidirectional.