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    could someone please help me im a bit confused as to why the myelin sheath increases the speed of action potential condiction when its an insulator if someone could explain would reallyyy helpp ! thanks
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    Where there is myelin, no exchange of ions can occur across the membrane. There are gaps in the myelin called nodes of Ranvier. If there was no myelin every single voltage gated channel would have to open and close as the action potential travels along the neuron. However because of the myelin the action potential kind of jumps between nodes of Ranvier, missing out huge chunks of the neuron and thus getting to the bouton faster. It's called saltatory conduction.

    Does that make sense? Harder to explain in text than I thought it would be! :P


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    (Original post by Adl91)
    could someone please help me im a bit confused as to why the myelin sheath increases the speed of action potential condiction when its an insulator if someone could explain would reallyyy helpp ! thanks
    Because myelin sheath are insulators, depolarisation can only occur at the nodes of Ranvier so then the impulse is forced to take another path and it does so by avoiding the myelinated neuron and instead jumps from one node to another, hence increasing their speed.
 
 
 
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