Question

Which type of substance movement should be facilitated?

Answer 1

Facilitated diffusion:

1. “Facilitated diffusion is a type of diffusion in which the molecules move from the region of higher concentration to the region of lower concentration assisted by a carrier.
2. It is the passive movement of molecules along the concentration gradient.
3. It is a selective process, i.e., the membrane allows only selective molecules and ions to pass through it.
4. In living systems, the lipid-based membrane creates compartments which allow the transport of a selective concentration of water-soluble substances.

Facilitated diffusion occurs for:

1. Substances having a hydrophilic moiety, find it difficult to pass through the membrane. Hence, their movement has to be facilitated.
2. Example: ions, small molecules, proteins, and other solutes.
3. Hydrophilic moiety is a water-loving part. They will dissolve in water but hydrophobic moiety are water fearful of water and they will not dissolve in it. The hydrophilic moiety has a powerful affinity for water so they dissolve in water as well as in other polar compounds.