Question

Answer the following question.

Discuss theories of water translocation.

Answer 1

Theories of water translocation:

1. Various theories have been put forth to explain the mechanism of translocation of water. These theories include the Vital force theory, Relay pump theory, Physical force theory, Root pressure theory, etc.
2. Root Pressure Theory (Vital Theory): This theory was proposed by J. Priestley. According to this theory, the activity of living cells of the root is responsible for the translocation of water.
3. Capillarity theory (physical force theory): This theory was put forth by Boehm in (1863). According to this theory, physical forces and dead cells are responsible for the ascent of sap.
4. Cohesion-tension theory (Transpiration pull theory): This theory was put forth by Dixon and Jolly (1894). This is presently a widely accepted theory explaining the ascent of sap in plants. This theory is based on two principles i.e. Cohesion and adhesion, and transpiration pull.