BIOL 1201 Lecture Notes - Lecture 11: Lipid Bilayer, Semipermeable Membrane, Cell Membrane
Document Summary
Cell membrane models (plasma membrane): cells, the minimum organization of living matter, fluid-mosaic model, 2 layers of phospholipids as before, but now exposed proteins in mosaic patterns, not a continuous layer pores bounded by protein as before. Phospholipid bilayer with mosaic of associated proteins. Inside ends = non-polar: proteins: some are stuck on some surfaces and others are embedded in membrane, cell coats: (not a separate entity from the cell membrane, (glycocalyx) composed of glycolipids & glycoproteins, function: Cell recognition: why do membranes exist, structural. Keeps contents from leaking out: functional: Controls things that happen inside the cell. Functional properties: maintain concentrations of molecules and ions, create free energy gradients, concentration differences = free energy differences, orient molecules into functional complexes, embed molecules in ways that make the process run smoother. Moves to the side where there is a lower concentration of water molecules. Which side has greater entropy: a.
