BIOL 2100 Lecture Notes - Lecture 7: Fluid Mosaic Model, Lipid Bilayer, Unsaturated Hydrocarbon

• School: University of Virginia
• Department: Biology
• Course: BIOL 2100
• Professor: Kittlesen David

Document Summary

7. 1: cellular membranes are fluid mosaics of lipids and proteins. Phospholipids are the most abundant lipids in most membranes. Most membrane proteins, like membrane lipids, are amphipathic. Fluid mosaic model- currently accepted model of the arrangement of molecules in the plasma membrane; the membrane is a mosaic of protein molecules bobbing in a fluid bilayer of phospholipids. Proteins are not randomly distributed in the membrane: groups of proteins are often associated in long-lasting, specialized patches, where they carry out common functions. Larry frye and michael edidin labeled plasma membrane proteins of a mouse cell and a human cell with two different markers and fused the cells. If membrane is rich in phospholipids with unsaturated hydrocarbon tails the membrane remains fluid to a lower temperature. Because of kinks in the tails where double bonds are located, unsaturated hydrocarbon tails cannot pack together as closely as saturated hydrocarbon tails, making the membrane more fluid: cholesterol.