Class 10 Biology - Osmosis in Potato

Aim

To demonstrate the process of osmosis in potato cells and observe the movement of water molecules across a semi-permeable membrane.

Cut a potato into two equal halves. Carve a small hollow cavity in the center of each half using a knife or spoon.
Label the two beakers as *A* and *B*. Fill beaker A with plain water and beaker B with a concentrated sugar solution.
Place one potato half in each beaker, ensuring the cavity faces upwards.
Add water to the cavity of the potato in beaker A and sugar solution to the cavity of the potato in beaker B.
Leave the setup undisturbed for 3-4 hours and observe the changes in the level of liquid in the cavities and the size of the potato halves.

After a few hours:

The cavity in the potato placed in water (beaker A) remains the same or may fill slightly due to water entering the cells.
The cavity in the potato placed in sugar solution (beaker B) shows a reduction in liquid as water moves out of the potato cells into the sugar solution.
The potato in beaker B shrinks slightly due to the loss of water, while the one in beaker A appears firm and turgid.

This experiment demonstrates the process of osmosis:

Osmosis is the movement of water molecules from a region of higher water concentration to a region of lower water concentration through a semi-permeable membrane.
In beaker A, water enters the potato cells due to osmosis, making them turgid.
In beaker B, water leaves the potato cells into the sugar solution, causing the potato to shrink (plasmolysis).

Ensure the potato slices are of similar size to observe clear differences in the results.
Handle the knife carefully to avoid injury while carving the potato.
Use fresh and clean water to avoid contamination affecting the results.
Leave the setup undisturbed during the experiment for accurate observations.