hey guys i need helpWatch
- short diffusion pathway
- size/mass of molecule
I'm sure there's a lot more but those are the only ones I can think of off the top of my head
Have a quick google search.
The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins.
Look at Wik for more of this stuff.