CELLSTRUCTURE细胞的结构ATerms.PPT

CELL STRUCTURE (細胞的結構) A. Terms 1. Cell - the basic unit of structure and function in living organisms. 2. Cytology - the study of cells, especially by microscopy. 3. Light microscope 4. Electron microscope Cell Structure  Cell wall (細胞壁) Cell membrane (細胞膜) Protoplast (原生質)- the living contents within the cell: nucleus (細胞核) and cytoplasm (細胞質) Cell membrane (細胞膜) Chemical components :consists of 60% protein (蛋白質) , 35% phospholipid (磷脂) and 5% polysaccharides (多糖) Two models: Unit membrane model(單位膜模型) Fluid mosaic model (流體鑲嵌模型) The Structure of Cell membrane Fluid mosaic model (流體鑲嵌模型). a three-layered ( trilaminar 三層 ) structure  ????????- Hydrophobic tails of two layers of phospholipid molecules point inward to form a phospholipid bilayer (磷脂分子雙層) , while the protein molecules is embedded in the phospholipid bilayer (嵌於磷脂分子之間) or transmembrane (跨膜). ?Fluidity (流動): due to the lateral movement (橫向) of phospholipid molecules. ?Mosaic(鑲嵌) : protein molecules are interspersed (散佈) among phospholipid molecules. ? Under electronic microscope The upper and lower darker regions in the 3 layered image of cell membrane corresponds to the_______ molecules and __________ portions of phospholipids whereas the middle light region corresponds to the ____________ tails of the phospholipid bilayer. Protein molecule The protein molecules were in form of g_________ protein which can be embedded in the phospholipid molecules or transmembrane. ? (1) membrane g___________ - as markers, recognition sites? (2) ________ proteins – transmembrane, have ________ / ionic channel that allows __ molecules and ions to pass through. They are for facilitated diffusion.? (3) ________ proteins - for facilitated diffusion ? (4) membrane bound proteins - single enzyme or aggregated to form multi-enzyme complexes to speed up chemical reactions. Function of cell membrane (i) Compartmentalization (分室作用) (ii) Co