Calculation of the Electrogenicity of the Sodium Pump System of the Squid Giant Axon
Ion pumps are essential constituents of cell membranes since they provide a means of compensating for ubiquitous membrane leaks and so help to maintain internal ion concentrations. In many cases these pumps generate electric current which can affect the membrane potential and are thus considered to be electrogenic. They are nearly always driven by the dephosphorylation of ATP and the process is known as active transport since it is able to transfer ions against existing electrodiffusion gradients. Thus, a mechanism driven by a biochemical reaction system has an electrophysiological result. The electrophysiological observations generated by the work of Kacy Cole have provided an important stimulus to some significant developments in membrane biochemistry.
KeywordsActive Transport Hole Area Squid Giant Axon Squid Axon Potassium Permeability
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