BIOM2011 Lecture 1: Epithelial Cells
Document Summary
Epithelial cells are essentially like gate keepers: primary role is the protective role, keeping out the external environment and only selectively allowing the diffusion and transport of molecules into the internal environment (nutrients, ions, glucose etc. ) Line all the surfaces exposed to air and the internal environment: secretory, cells which can secrete molecules, ductal cells, absorptive cells, kidneys absorb ions, sensory cells, specialised epithelial cells, lubricating, secrete fluid. Lungs, intestine: cells are all around body and vital to live. Because there are two different membranes it means the cells are polarised: apical membrane is different to the basal membrane. Important in ion transport, fluid section and nutrient secretion/absorption. Integrin"s bind to particular proteins in the basement membrane (fibronectin, laminin and collagen structural proteins: have attachment proteins which help attach actin filaments (vinculin and talin) Important for allowing cells to migrate and to move. Important in maintaining the polarity (the difference between the apical membrane and the basal membrane)
