Question

Which of the following forces is/are responsible for the ascent of sap?

• A. Root pressure
  
• B. Capillary force
  
• C. Transpirational pull
  
• D. All of the above

Answer 1

The correct option is D

All of the above

There is a limited rise of water in narrow tubes or capillaries due to forces of cohesion amongst molecules of water and their property of adhesion to other substance. This is called capillary force or capillary action.

Root pressure is the positive pressure that pushes sap from below due to active absorption by root.

Transpiration in aerial parts brings the xylem sap under negative pressure or tension due to the continuous withdrawal of water by them.