NEET Class neet Answered

The most important factor for absorption of water in plants is cohesive force of water.

Cohesion and transpiration pull theory is the most widely accepted theory for ascent of sap. The water molecules have a great mutual attraction with one another, that is, they have tremendous cohesive power which is sometimes as much as 350 atmospheres. Thus the transpiration pull developed a negative pressure in the uppermost xylem cells is transmitted from there into the xylem of stems, and from there to the roots.

In this way the water rises due to the transpiration pull and the cohesive power of water molecules from the lowest parts of the roots to the highest peaks of the trees.