Identify the difference between facilitated diffusion and regular diffusion.

a)in facilitated diffusion, substances move from areas of lower concentration to areas of higher concentration. in regular diffusion, substances move in the opposite direction.
b)facilitated diffusion is a form of active transport. regular diffusion is a form of passive transport.
c)facilitated diffusion involves special membrane proteins that transport substances across the cell membrane. regular diffusion does not involve proteins.
d)facilitated diffusion requires an input of energy to transport substances across the cell membrane. regular diffusion does not require an input of energy.