What is the role of adhesion and cohesion of xylem sap?

Adhesion and cohesion are crucial for the movement of xylem sap in plants. Cohesion, the attraction between water molecules, helps maintain a continuous column of sap, preventing it from breaking during ascent. Adhesion, the attraction between water molecules and the xylem vessel walls, assists in drawing the sap upward against gravity. Together, these properties enable efficient water transport from roots to leaves, supporting vital physiological processes like photosynthesis.