Biology 2382B Lecture 15: Lecture 15 - Membrane Proteins
Document Summary
Allow for specialized cell function to occur and be localized. Due to amphipathicity, phospholipids spontaneously form lipid bilayers in aqueous solution where properties of the fatty acids confer properties onto the bilayers. A long hydrocarbon chain attached to a polar carboxyl head group. Lots of different fatty acids - different ones used for different properties. Fluidity - big property, v. important, has to be fluid (in humans) at. We want it between fats and oils. Longer fatty acid chain = higher melting point. You can move laterally within a bilayer, but you never get a phospholipid form one side of the membrane moving to the other - no movement between leaflets. Cholesterol can either raise or lower fluidity. Limits how things can move through the membrane. These proteins can be linked to cytoskeleton or ecm or both. Diffusion 10x slower in pms that pure bilayers.