Movement of xylem sap from roots to leaves

Question

Quizplus · Accepted Answer

Xylem sap movement from roots to leaves usually depends on tension, or negative pressure potential. This is known as the transpiration-cohesion-tension mechanism, where water is pulled up through the xylem due to the negative pressure potential created by transpiration in the leaves. This is an example of a passive transport mechanism, as it does not require energy input from the plant. The apoplast of sieve-tube elements and active transport are not directly involved in xylem sap movement, and while aquaporins may facilitate water movement within the plant, they do not play a major role in the overall movement of xylem sap from roots to leaves.

Movement of Xylem Sap from Roots to Leaves