IMED1001 Lecture Notes - Lecture 12: Electrochemical Gradient, Luigi Galvani, Lipid Bilayer

• School: UWA
• Department: Integrated Medical Sciences
• Course: IMED1001
• Professor: avinash

Document Summary

Animal electricity: around 1785, luigi galvani dissected a frog while standing near a static generator -> the tou(cid:272)h (cid:373)ade the frog(cid:859)s leg t(cid:449)itch, electro-stimulation of deceased limbs (performed on the executed criminal george. Huge concentration gradient of sodium and potassium, this is due to sodium potassium pump. Io(cid:374)s do(cid:374)(cid:859)t diffuse a(cid:272)ross the (cid:373)e(cid:373)(cid:271)ra(cid:374)e u(cid:374)less (cid:449)e let the(cid:373)-> they change the positive and negative across the membrane-> the membrane potential. Opening sodium or potassium channels to change this membrane potential. 155mm: massive concentration gradients for na+ and k+ Burns through 1 atp to drive 3na out and 2k in sets up conc gradient an electrical gradient charge gradient set up by ions. Diffusion of ions: diffusion of ions is determined by: Membrane permeability concentration gradient voltage gradient inside of cell is negative so positive ions want to come and vice versa. Resting membrane potential cytoplasm of typical cells is electrically negative (around 70 mv) with respect to extracellular fluid.