TRANSPORT – Diffusion
Diffusion – Net movement of molecules/ions from a region of high to low conc.
Process:
- Passive = no energy required
- Continues until reaches equilibrium
- Small uncharged particles diffuse through membrane whilst hydrophobic molecules move through channels in the bilayer (b/c they can’t travel through hydrophilic heads)
- The selective permeability of biological membranes to small molecules allows the cell to control and maintain its internal composition