BIOL 1201 Lecture Notes - Lecture 8: Semipermeable Membrane, Glycolipid, Glycocalyx
Document Summary
Biol 1201 lecture 7 membrane concepts. 2 layers of phospholipids as before, but now exposed proteins in a mosaic patterns, not a continuous layer pores bounded by protein as before fluidity: proteins and phospholipids can move (dynamic structure), evidence from hybrid cells. [clicker]: the highlighted region of the integral protein would be expected to contain: yellow (middle)-nonpolar amino acids; pink (top)-polar amino acids. Cell coats: (not a separate entity from the cell membrane) glycocalyx composed of glycolipids and glycoproteins. Why do membranes exist: structural, functional properties: more important than structure, maintain concentrations of molecules and ions, create free energy gradients, orient molecules into functional complexes. Osmosis: net movement of water across a semi-permeable membrane (ie permeable to water, but not to solutes) Factors involved in the permeability size and shape of molecules solubility in lipids net electric charge chemical properties.
