How does facilitated transport differ from diffusion?
Facilitated transport needs a channel protein for the material to to pass across the membrane, while diffusion does not need it.
Facilitated diffusion is for polar or charged molecules which are relatively small in size, while diffusion is for small particles which are neither polar nor charged that need to cross the cell membrane.
Facilitated diffusion happens across the cell membrane, while diffusion happens in any solution regardless of the presence of cell membrane or not.
This video explains the role of membrane channels in the process of facilitated diffusion.
Video from: Noel Pauller
Hope this helps!