Describe a semipermeable membrane.

A semipermeable membrane is a barrier that will only allow some molecules to pass through while blocking the passage of other molecules. A semipermeable barrier essentially acts as a filter. Different types of semipermeable membranes can block out different sized molecules. A semipermeable membrane can be made out of biological or synthetic material.

Explanation:

A semipermeable membrane is a type of biological or synthetic, polymeric membrane that will allow certain molecules or ions to pass through it by osmosis—or occasionally by more specialized processes of facilitated diffusion, passive transport or active transport.