Question

In an experiment, two sets of apparatus were set up as shown below:
In A there is a concentrated sugar solution inside the thistle funnel and red ink in the water outside the funnel. In B there is a concentrated glucose solution with red ink inside the thistle funnel and water outside the thistle funnel.
In both A and B the level of liquid inside the funnels rises up the tubes. In A the sugar solution turns red and in B, the water turns red.
Study the given observations and answer these questions:

1. Name the process by which red ink moves in A and B.
2. Which type of pressure forces the water molecules to move towards thistle funnels and cause a rise in the water level?
3. Where does this process occur in plants and animals?
4. What material could be used as a semi-permeable membrane?

Answer 1

(i) Osmosis.
(ii) Osmotic pressure.
(iii) In plants, in the root cells and in animals in the RBC’s.
(iv) Cellophane paper or goat bladder, etc.