The physiological process, osmosis can be demonstrated using
A. Potometer
B. Bell jar experiment
C. Thistle funnel whose mouth is tied with egg membrane
D. Thistle funnel whose mouth is tied with paper

Hint: Osmosis is the process of movement of solvent particles from the region of higher concentration to region of lower concentration across a semipermeable membrane.

Complete Answer:
For osmosis to take place, the main requirements in a system are Concentration difference in the medium and a semi- permeable membrane. Semi permeable membrane is a membrane which allows selective passage of solvent molecules across the membrane.

Option (A) potometer- A potometer is a device used to measure the rate of water uptake by a leafy plant shoot. It shows the water uptake by a cut shoot is due to transpiration.

Option (B) Bell jar experiment- It is an experiment used to demonstrate that sound requires a medium to propagate.

Option (C) - Thistle funnel whose mouth is tied with egg membrane- This setup can be used to demonstrate osmosis. The solvent gradient can be maintained by placing the funnel in the hypertonic solution. The inside of the funnel contains only solvent. The egg membrane acts as a semipermeable membrane which allows only the movement of solvent. The level of the solvent inside the funnel will decrease showing exo-osmosis.

Option (D) - Paper does not act as a semi permeable membrane. Thus this setup will act as a control.

The correct answer is (C). Osmosis can be demonstrated using a thistle funnel whose mouth is tied with egg membrane.

Note: The outward movement of water from the cell is called exosmosis. It leads to shrinkage of the cell. The inward movement is called endosmosis. It leads to swelling of the cell. The cell membrane acts as a semipermeable membrane.