Question

Swelling up of a raisin on keeping in water is known as Osmosis.
A. True
B. False

Answer 1

Osmosis is a process in which the movement of particles takes place from lower concentration to higher concentration through a semipermeable membrane. In the comparison of pure water and raisin, pure water has very little solute concentration than the raisin. So water molecules move from lower to higher concentration.

Complete answer:
Osmosis is a process in which the movement of particles takes place from lower concentration to higher concentration through a semipermeable membrane. In the case of raisin and pure water, pure water has very little solute concentration than the raisin. So, particles move through water that is lower concentration to the raisin that is higher concentration. Due to which the raisin gets swell up and this process takes place is named as osmosis.It is true that swelling up of a raisin on keeping in water is known as osmosis.

Hence, option A is correct.

Additional information:
Osmosis is a very important process biologically. All the biological membranes are semipermeable in nature that means they allow the particles to pass through them. But also these membranes are not permeable to large size molecules and polar molecules for example ions, proteins, and polysaccharides, but being permeable to nonpolar or hydrophobic molecules such as lipids as well as to small molecules for example oxygen, carbon dioxide, nitrogen, and nitric oxide.

Note:
There is also a process that is just reverse of the osmosis. That process is called reverse osmosis. Reverse osmosis is a process which is used for water purification. In this process a partially permeable membrane is used to separate ions and the unwanted molecules. This process takes place when pressure greater than osmotic pressure is applied so that the movement of ions gets reversed and hence named as reverse osmosis.