Water movement from soil into plant roots and subsequently into upper portion of the plant is partly due to phenomenon of
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Osmosis
Osmosis is the net flow of solvent through a semipermeable membrane from the pure solvent (or a dilute solution) into a more concentrated solution. Only solvent molecules pass through the membrane, and the flow continues until the concentrations are balanced or it is stopped by pressure.
The cell sap in the root hairs of a plant is more concentrated than the water in the soil. Water therefore passes through the cell membranes into the roots by osmosis, and from cell to cell towards the upper parts of the plant.
Why the other options are incorrect
Option (1) Edema — Incorrect. Edema is the swelling of body tissues when water is retained in the cells, for example after eating too much salt. It is a result of osmosis in animals, not a way of moving water in plants.
Option (3) Reverse Osmosis — Incorrect. In reverse osmosis the solvent is forced from the solution into the pure solvent by applying a pressure larger than the osmotic pressure. It does not happen naturally in roots.
Option (4) Evaporation — Incorrect. Evaporation of water from the leaves helps pull water up through the plant, but it is not the process by which water crosses the root membranes from the soil.
NCERT (2026-27 edition):
Osmosis and Osmotic Pressure – “… The phenomena mentioned in the beginning of this section can be explained on the basis of osmosis. A raw mango placed in concentrated salt solution loses water via osmosis and shrivel into pickle. … People taking a lot of salt or salty food experience water retention in tissue cells and intercellular spaces because of osmosis. The resulting puffiness or swelling is called edema. Water movement from soil into plant roots and subsequently into upper portion of the plant is partly due to osmosis.”