Cell Membrane and Diffusion
Cell Membrane and Diffusion
Diffusion across cell membranes is just like simple diffusion in air, PARTICLES flow through cell membrane from a region of HIGH CONCENTRATION (many of them) to a region of LOW CONCENTRATION (only a few of them). This is constantly happening in your lungs.
Cell membranes hold everything inside a living cell. However, for a cell to function properly they let stuff in and out as well. These membranes are quite choosey. They only allow very small molecules to diffuse through them - stuff like glucose and/or amino acids.
Large molecules like PROTEINS and/or STARCH can't diffuse through cell membranes.
