细胞生物学_05物质的跨膜运输重要参考

1、LOWTransport Passive Simple diffusionOsmosisActivetransportl不需要能量，自发发生不需要能量，自发发生l动力来自浓度差别，不需要外界帮助，顺动力来自浓度差别，不需要外界帮助，顺浓度剃度运输浓度剃度运输5. 1 Passive transportl需要能量需要能量l低浓度运输导高浓度，逆浓度低浓度运输导高浓度，逆浓度l转运蛋白参与转运蛋白参与Active transport5.1.1 DiffusionIf a concentration gradient exists, there will be a net flow of mater

2、ial across the membrane高高低低Hypotonic低渗低渗Hypertonic高渗高渗isotonichypotonichypertonic等渗等渗5.1.3 Facilitated Diffusion协助扩散协助扩散Na+glucoseMembrane Trans. Protein A Carrier protein B Channel protein Carrier protein change shape let material transportChannelTypes of channel protein or ion channel Brief summar

3、y of passive transport +Charged particle cloaked with water molecules, can not get throughNa+Cl-K+H+Large molecules, also cloaked with water molecules, can not get throughNucleotidesAmino acidsSugarsThree ways of driving active transport. Active transporthttp:/www.cat.cc.md.us/courses/bio141/lecguid

4、e/unit1/eustruct/sppump.htmlQuestion: Compare with glucose transport by facilitated transport and active transport ? Aniport 运输小泡与靶膜融合运输小泡与靶膜融合 Endocytic vesicle forming mechanism 大部分回到质膜重新利用大部分回到质膜重新利用少数进入溶酶体，受体下降调节少数进入溶酶体，受体下降调节 (receptor down regulation) 少数运输到质膜不同区域少数运输到质膜不同区域6. 转胞吞作用：受体和配体不作任何处理，转胞吞作用：受体和配体不作任何处理，内吞物从极性细胞一侧转到相反的方向。内吞物从极性细胞一侧转到相反的方向。母乳喂养之所以可以给宝宝抗体正是转胞母乳喂养之所以可以给宝宝抗体正是转胞吞作用原理实现的。吞作用原理实现的