Neurons like all living cells are surrounded by a plasma membrane that is impermeable to ions this property allows a neuron to maintain different concentrations of ions between the inside and outside of the cell and an alien there is a large difference in the concentration of ions such as sodium and potassium.In a typical million you're on there is a large difference in the concentration of ions such as sodium and potassium between the intracellular and extracellular environment in addition the interior of a neuron has a high concentration of organic anions including proteins and nucleic acids the plasma membrane is composed of a lipid bilayer hydrophobic nature the only way I know.Since the diffusion of ions across the membrane the only way I can diffuse across the lipid bilayer is my passing through specialized channels these channels are transmembrane pores that permit the movement of protected or ions while excluding others such as channels can be in an open or closed steak when a neuron is at rest most ion channels are closed however some potassium channels are open for many potassium ions diffuse out of the cell down their concentration gradient no sodium channels are normally closed and sodium ions across the membrane when a neuron is at rest in a typical neuron the concentration of potassium is higher than the actual concentration to opposing forces influence the movement of potassium ions.First Diffusion Force drives for Tennessee and ions down their concentration gradient towards the exterior of the cell the movement of potassium ions out of the cell increases the internal negative charge the positively charged potassium ions are attracted to the internal negative charge and this electrical force pulls potassium ions back into the cell the diffusion and electrical forces eventually come into balance and an electrical potential or voltage is reached at which the electrical force exactly at this point...What is the diffusion Force at this point there is no net movement of potassium ions into or out of the cell the electrical potential across the membrane can be measured by inserting an electrode into the cell has a voltage difference of about -16 Volt across the membrane this value is the neurons resting membrane potential and just governed by the relative concentrations of ions species between the intracellular and extracellular space.
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