Question

When raisins are kept in water, they get swollen. Name the phenomenon involved in this process.

Hint:

"Endo" means inward. Water moving into a cell is Endosmosis.

Answer 1

Step 1: Concept
Movement of solvent across a semi-permeable membrane.

Step 2: Meaning
Water moves from an area of lower solute concentration (outside) to higher solute concentration (inside the raisin).

Step 3: Analysis
Water enters the raisin cells by osmosis, causing the cells to swell and increasing the size of the raisin.

• A raisin contains a concentrated solution of sugars and other dissolved substances inside its cells.

• When a raisin is placed in pure water or a dilute solution, the surrounding solution is hypotonic relative to the cell sap.

• The cell membrane behaves as a selectively permeable membrane.

• Water molecules therefore move into the raisin cells through the process of osmosis.

• Osmosis is the movement of solvent molecules from a region of lower solute concentration to a region of higher solute concentration through a semipermeable membrane.

• As water enters the cells, the internal pressure (turgor pressure) increases.

• Consequently, the cells expand and the raisin swells.

• Thus, the increase in the size of the raisin is a direct consequence of endosmosis.

Step 4: Conclusion
This specific biological process is called endosmosis.

Final Answer: Endosmosis (or Osmosis)