1、第一篇 細(xì)胞生理學(xué) 第一章 生物膜的物質(zhì)轉(zhuǎn)運功能 第二章 細(xì)胞的興奮 第三章 細(xì)胞間信息傳遞 第四章 肌細(xì)胞的收縮功能第一章 生物膜的物質(zhì)轉(zhuǎn)運功能from Berne & Levy Principles of Physiology (4th ed) 2005Chap. 1 Cellular Membranes and Trans-membrane Transport of Solutes and Water Cell membrane serves as a permeability barrier that allows the cell to maintain a cytoplasmic

2、composition far different from the composition of the extracellular fluid. The membranes that enclose the various organelles divide the cell into discrete compartments and allow the localization of particular biochemical processes in specific organelles. Singer 流動鑲嵌模型Simple Diffusionvia carriers Fac

3、ilitated DiffusionSaturation: as the concentration of the transported compound is increased, the rate of transport at first increases, but eventually a concentrations reached after which the transport rate increases no further.Specificity: only molecules with the requisite chemical structure are tra

4、nsported.Competitive inhibition: structurally related molecules may compete for transport. water channelion channels葉公杼和詹裕農(nóng)Shaker鉀通道Ionic selectivity:Activation:voltage-gated, ligand-gated, mechanosensitive or background current channel離子通道的隨機(jī)活動 primary active transport has a direct link to metaboli

5、c energy, via pumps. Active Transport secondary active transport derives energy from the concentration gradient of another substance that is actively transported, via symporter or antiporter (exchanger).鈉鉀泵細(xì)胞的鈣轉(zhuǎn)運系統(tǒng) Endocytosis and Exocytosisreceptor mediated endocytosisphagocytosisfluid phaseendocytosis simple diffusion primary active transport endocytosis & exocytosis facilitated diffusionporesion