- Slides: 72
Cell Membrane 细胞膜 cell membrane n 质膜 plasma membrane n
The outer membrane boundary of the cell. n It protects the cell , gives it shape and controls materials transport , detects and transmits signal. n The most important character of cell membrane is selective permeable ( semipermeability ) n
膜性结构 membranous structure n 细胞内膜系统 endomembrane system n Compartmentalization 区域化 n 生物膜 biological membrane n 单位膜 unit membrane n
Lipid n Protein n Carbohydrate n n 化学成分的比例可出现较大差异
n 脂质双分子层 lipid bilayer ： provides the basic fluid structure of the membrane and serve as a relatively impermeable barrier to the passage of most water-soluble molecules.
n 整合蛋白 (Integral proteins)： penetrate or are embedded in the phospholipid bilayer. some membrane proteins have one or more alpha-helical regions that can span the bilayer multiple times.
n 边周蛋白 (Peripheral proteins)： linked only at the cytoplasmic surface by attachment to a fatty acid chain, or at the external cell surface by bound to other membrane proteins.
n 脂锚定蛋白 lipid-anchored protein bound covalently to one or more lipid molecules. The polypeptide chain does not enter the phospholipid bilayer.
脂筏（lipid raft） n Lipid rafts are defined as plasmamembrane microdomains enriched with glycosphingolipids and cholesterol which render them insoluble in non-ionic detergents.
内膜系统 n The endomembrane system is the system of internal membranes within eukaryotic cells that divide the cell into functional and structural compartments, or organelles. endoplasmic reticulum, Golgi complex, lysosome, peroxisome…
内质网 endoplasmic reticulum, ER : n an organelle found in all eukaryotic cells. n a network of tubules and vesicles that are interconnected and often extends throughout most of the cell.
n Synthesize membrane lipids and proteins, makes macromolecules, and transfers substances throughout the cell.