跨膜转运.ppt

Membrane Transport
Xia Qiang, MD & PhD
Department of Physiology
Rm C518, Block C, Research Building, School of Medicine
Tel: 88208252
Email: ******@
Sizes, on a log scale
Cell: building block & functional unit
A typical animal cell and its organelles
Electron Micrograph of organelles in a hepatocyte (liver cell)
Organelles have their own membranes
Cell Membrane (plasma membrane)
Electron micrograph and sketch of plasma membrane
surrounding a human red blood cell
Phospholipid bilayer
Circles represent amino acids in
the linear sequence of the protein
Schematic cartoon of a transmembrane protein
The amino acids along
the membrane section
are likely to have
non-polar side chains
Structure of cell membrane:
Fluid Mosaic Model (Singer & Nicholson, 1972)