BIOCH200 Lecture Notes - Lecture 21: Lipid Bilayer, Membrane Technology, Close-Packing Of Equal Spheres

• School: University of Alberta
• Department: Biochemistry
• Course: BIOCH200
• Professor: Jonathan Parrish

Document Summary

Maintaining membrane fluidity: cholesterol isn"t that important for membrane, adapting to difference in temperature will affect the lipid composition of a, cholesterol, variation in lipids can happen, but you can still synthesize new ones! Cholesterol increase membrane rigidity (in animals) biological membrane. Temperature = unsaturated fatty acids = length of chains. Limits the rotational movement of neighboring acyl tails. Low temperature: prevents close packing of acyl chains. High temperature: decreases motion/disorder of acyl chains and increases rigidity. Lipids move freely and rapidly in the bilayer: only laterally. Within the context of its own leaflet: not transverse diffusion. This is because polar heads are going to have to pass through the hydrophobic core, which is. Significant energy barrier to desolvate a polar head group. Flipases does help to increase this transverse diffusion motion. Specific transport by these proteins allow for differences in lipid composition in the leaflets.