Multiple choice

Which of the following is the most accepted theory of ascent of sap?

  1. Capillary theory

  2. Root pressure theory

  3. Pulsation theory

  4. Transpiration theory

  5. -

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The cohesion of water explains only maintenance of the sap column. The explanation for the upward movement of the water is accounted for by a mechanism, called transpiration pull, that involves the evaporation of water from leaves. It is the most accepted theory for ascent of sap.