How does the cell membrane affect diffusion?
The diffusion through the membrane are of the simple and facilitated type.
The simple passive diffusion occurs when small molecules pass through the cell membrane.
The facilitated diffusion depends on carrier proteins that are impregnated in the cell membrane.
The carrier proteins allow specific substances to cross the membrane and disallow to cross the undesirable molecules through the cell membrane.
"video explains the role of membrane channels in the process of facilitated diffusion.
Video from: Noel Pauller