Question

Which of the following contributes most to the transport of water from the ground to the leaves of a tall tree?
(a) Breakdown of ATP
(b) Capillary rise of water in the xylem
(c) Cohesion of water and transpiration pull
(d) Root pressure

Answer 1

Hint: They are the loss of water from the plant by evaporation at the surface of the leaf. They are the main operator of water motion in the xylem. They create negative pressure (tension). Water from the roots is elevated through this tension.

Complete answer:
The cohesion of water and transpiration pull contributes most to the transport of water, from the bottom to the leaves of a tall tree. It is the phenomenon of affinity between related molecules. The strong cohesive force maintains an endless channel for water. The transpirational pull is the pulling force liable for lifting the water column.

As water is vanished in sort of water vapor to the atmosphere from the mesophyll cells through transpiration, a negative hydrostatic pressure is made within the mesophyll cells which in order pull out water from the veins of the leaves. Therefore, the transpiration pull functions as pull from above on-the-whole of the water column of the plant which propels the water column of xylem vessels of roots through to leaves that are in an upward direction.

Additional information: Plants contain a huge network of conduits that contain xylem and phloem. This is identical to the circulatory system that transports blood all over the human body. Identical to the circulatory system in humans, the xylem and phloem tissues expand all over the plant. These conducting tissues arise from the roots and move up by the trunks of trees. Later they branch off into the branches, then branch even further into every leaf, like spider webs. Transportation occurs in three levels within the case of plants - Transportation of substance from one cell to another. - Long-Distance Transport of sap within phloem and xylem. - The discharge and uptake of solute and water through independent cells.
So, the correct answer is '(c) Cohesion of water and transpiration pull'.

Note: In the occurrence of transportation in plants, the greatest restriction is water as it ends up being a limiting factor in development. To overcome this problem, trees and other plants have the right system for the absorption and translocation of water.