Question

How does facilitated transport work?

Answer 1

Facilitated diffusion:

1. Facilitated diffusion is the diffusion of solutes through transport proteins in the plasma membrane.
2. Facilitated diffusion is a type of passive transport.
3. Even though facilitated diffusion involves transport proteins, it is still passive transport because the solute is moving down the concentration gradient.
4. Small nonpolar molecules can easily diffuse across the cell membrane.
5. However, due to the hydrophobic nature of the lipids that make up cell membranes, polar molecules (such as water) and ions cannot do so.
6. Instead, they diffuse across the membrane through transport proteins.
7. A transport protein completely spans the membrane and allows certain molecules or ions to diffuse across the membrane.
8. Channel proteins, gated channel proteins, and carrier proteins are three types of transport proteins that are involved in facilitated diffusion.