人体2erfegf(国外英文资料).docVIP

人体2erfegf(国外英文资料) The cell membrane has the barrier function, the transport function, the transmembrane information transmission function, the function of membrane excitability. The molecular structure of a cell membrane, and its composition The cell membrane is mainly composed of lipid (lipid) and protein (protein), in addition to a very small amount of carbohydrate. The molecular structure of the cell membrane, has now been recognized that hypothesis is liquid model proposed by Singer and Nicholson in 1972 (fluid mosaic model), which is in liquid lipid bilayer as base, which is studded with diverse structure and function of protein. The lipid bilayer in the liquid lipid bilayer as base, with stability and liquidity. Keep the barrier function, cell content is relatively stable. Cell membrane proteins: mosaic or through the lipid bilayer. A variety of functions, such as membrane channel protein, carrier protein, enzyme, cell and material, energy and information exchange. Cell membrane carbohydrate: for short sugar chains, combined with covalent bond with membrane lipids or proteins, forming glycolipids or glycoproteins. As some epitopes = immune information (blood group); some as a membrane receptor recognition, specifically with laser combined transmitter. Two, the transport of cell membrane The degree of difficulty: material permeability membrane. Transmembrane transport: material ions, small molecules and macromolecules such as protein and droplet mass of solid material, such as import cell. Divided into the transmembrane transport of simple diffusion, and Mo mediated endocytosis and exocytosis. (a) simple diffusion Concept: refers to the fat soluble substance from high concentration side of the membrane to low concentration of the mobile side. Transfer material: O2, CO2, NH3, N2, urea, ethyl ether, ethanol, steroids and so few, because the water molecules can also be minimal, through free bilayers. Penetration: solvent solute movement by attracting penetration b