Question

the image shows facilitated diffusion. how is it different from simple diffusion? facilitated requires a protein channel no difference, just another term for the same thing facilitated goes against the gradient; simple goes with the gradient

Explanation:

Simple diffusion is the passive movement of substances from an area of higher concentration to an area of lower concentration without the help of membrane - bound proteins. Facilitated diffusion also moves substances down their concentration gradient but requires a protein channel (or carrier protein) to assist the movement of larger or polar molecules across the cell membrane.

Answer:

facilitated requires a protein channel