Question

Read the given statements and select the correct ones. (i) A membrane which permits the passage of pure solvent molecules to pass through it and not the solute particles is called semi-permeable. (ii) A membrane which allows some substances to pass through it more readily than others is known as selectively/ differentially permeable. (iii) All living biological membranes are perfectly semipermeable.

• A. (i) and (ii)
• B. (ii) and (iii)
• C. (i) and (iii)
• D. (i), (ii) and (iii)

Answer 1

The Correct Option is A

There are certain membranes, which allow penetration of only solvent molecules but not the solute particles. Such membranes are known as semi-permeable. Examples of such membranes are cellophane, fish and animal bladders, egg membrane, plasma membrane, etc. The biological membranes are not perfectly semi-permeable. They allow to pass solute molecules only up to a certain extent and are, therefore, selective in nature. They are known as selectively or differentially permeable membranes. All living biological membranes are differentially permeable membranes, which allow some substances to pass through it more readily than others.