Discuss the factors responsible for ascent of xylem sap in plants.

The factors that responsible for the ascent of sap are 1.Cohesion – This is a mutual attraction between water molecules. 2.Adhesion – An attraction of water molecules to polar surfaces (such as the surface of tracheary elements) is known as adhesion. 3.Surface Tension – The water molecules are attracted to each other in the liquid phase more than to water in the gas phase.