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Facilitated diffusion

Can someone give me an A* a level definition of facilitated diffusion please :smile:

"There are three different carrier mechanisms in mammalian physiology. One of them is facilitated diffusion, brought about by a so-called uniporter. It involves the movement of a single substance down its concentration gradient via a channel across a lipid bilayer (unit membrane) - it is facilitated in the sense that the path of diffusion is of low resistance. An example is the GLUT1 glucose transport mechanism."

((THIS PART IS NOT NECESSARY IN THE DEFINITION: the other two carrier mechanisms are the symporter and antiporter phenomena.))

Reply 2

HateOCR

Allows polar molecules to pass the phospholipid bilayer via specific channel proteins.
Also a carrier protein which changes shape to allow larger molecules to enter the cell (but it must be from high to low concentration)
This isn’t an “A*” definition but i hope it helps.