BIO 320 Lecture Notes - Lecture 2: Apoptosis, Membrane Protein, Lipid Bilayer
Document Summary
So important for cells and biological organization: protective physical barrier, selective chemical barrier, enables compartmentalization, concentrates certain molecules, localization of specific reactions, supports 2d diffusion. Plasma membrane is a phospholipid bilayer that can be made up of 50% protein. 3 major classes: (know the main structural differences and common features of these molecules: phospholipid (phosphoglyceride, sphingomyelin, glycolipid, cholesterol. *note that two of these classes have sphingolipids. *know the structural similarities between these molecules and the key differences glycerol vs sphingosine, fatty acid tail length and shape, net charge, etc. Membrane fluidity: an important feature of membranes that allows lateral diffusion of molecules in various conditions (e. g. hot vs cold temperature: to maintain a certain state of membrane fluidity, the molecular composition of membranes will change. Fatty acid chain length and saturation know how length and saturation (cis- vs trans-) affect fluidity: lipids and diffuse laterally, flex, rotate, and flip-flop.
