Question

Mowgli likes grapes a lot. He once got a huge bunch from a tree, but they were shriveled up. Baloo told him soak them in the bowl of pure water he had with him. Mowgli listened to Baloo and put them in there when his mother Raksha called him.
He came back after 2 hours and observed something. What did he observe?

• A. The grapes became smaller.
• B. The grapes increased in number.
• C. The grapes became round.
• D. The grapes remained the same.

Answer 1

The correct option is C The grapes became round.

Mowgli would have observed that the grapes swelled up and they looked a lot better, so he enjoyed eating them.
Here, pure water has a lower solute concentration, and grapes also contain water but with many solutes, giving it a higher solute concentration. Also, the outer covering of grape acts as a semi-permeable membrane selectively allowing water but not other solutes to flow across.
By the process of osmosis, water molecules flow from a region of higher solute concentration to a region of lower solute concentration. This made the water flow from pure water into the grapes. This happened for quite a while which eventually made the grapes swell.
This process is specifically known as endomosis.
Endosmosis is the process by which a cell expands due to the movement of solute molecules into the cell across a semi-permeable membrane.
Clearly, the cell in this context is the grape which is covered by a thin outer covering which acts as the semi-permeable membrane.