Demonstration of Osmosis process by Thistle Funnel Method

Introduction

Aim of the Experiment

Requirements:-

Procedure for the experiment

Result

Precautions:-

1. The egg's membrane has to be tightly fastened to the mouth of the funnel.
2. The initial level of sugar solution in the thistle funnel should be carefully noted.

Questions and answers related to the experiment

1. What is the process demonstrated with the above experimental setup and define it?
Ans. The phenomenon demonstrated in the above experimental setup is osmosis. Osmosis can be defined as the movement of water molecules from a dilute solution to a concentrated solution through a semi-permeable membrane.

2. What would you observe in the experimental setup after an hour or so? Explain the change observed.
   Ans. There will be increase in the level of sugar solution in the stem of the Thistle Funnel because water molecules from beaker entered into it through the egg's membrane which is a semi-permeable membrane.

Here is an experiment on Experiment on Transpiration in plants with dicot leaves

3. Why a control setup was used for this experiment?
   Ans. By using a control setup we can clearly prove through that in osmosis process water molecules are only moving from a dilute solution to a concentrated solution through a semi-permeable membrane.


4. Keeping in mind the root hair cell and its surroundings, name the parts that corresponds to concentrated sugar solution (1), egg's membrane paper (2), and water (3) in the beaker.
   Ans.
   1. Concentrated sugar solution in the Thistle Funnel corresponds to cell sap of root hair cell
   2. Egg's membrane corresponds to cell membrane of root hair cell
   3. Water in the beaker corresponds to soil solution.
      
5. Name any other substance that can be used instead of egg's membrane in the above experiment?
   Ans. Parchment paper, Cellophane paper, Goat's bladder membrane.


6. What is the nature of egg's membrane used in the above experiment?
   Ans. Egg's membrane acts as a semi-permeable membrane in the above experiment. A semi-permeable membrane is a membrane which allows smaller particles like water molecules through it but prevents the movement of larger particles like sugar or salt particles.


7. Name the two conditions required for osmosis to occur in the above experimental setup?
   Ans.
   1. Presence of semi-permeable membrane (Egg's membrane)
   2. Different concentration of solutions in Thistle Funnel and Beaker
   
   
8. What is the tonocity of the solution kept in the Thistle funnel of experimental setup and control setup? Define them.
   Ans. The tonocity of solution kept in the Thistle funnel of experimental setup is Hypertonic solution. A solution which is more concentrated in nature when compared to the surrounding solution is known as Hypertonic solution.
   
   The tonocity of solution kept in the Thistle funnel of control setup is Isotonic solution. A solution which is equal in concentration with surrounding solution is known as Isotonic solution.

Here is an experiment on How to measure the rate of transpiration of a cut twig with Ganong's Potometer

9. Give three significance of osmosis in living beings.
   Ans.
   1. Osmosis play an important role in the absorption of water by the roots of the plants from soil.
   
   
   2. Osmosis regulates the opening and closing of stomata.
   
   
   3. Osmosis maintains osmotic balance i.e. osmoregulation in animals.
   
   Here is a video of Osmosis experiment:-
   
   Courtesy:- Youtube.com