Question

Differentiate between active absorption through osmotic mechanism and through non-osmotic mechanism.

Answer 1

Active absorption occurs as a result of activities in the root and does not concern the shoot. In this process, an expenditure of metabolic energy may be required for water absorption. Water absorbed by osmotic mechanism does not require directly an expenditure of energy. The energy is utilized in the absorption and accumulation of salts. The Water movement occurs along the gradients of diffusion pressure deficit (DPD).

On the other hand, water absorption through non-osmotic mechanism involves direct expenditure of metabolic energy. It occurs against a diffusion pressure gradient.