In this video Paul Andersen details the action potential in neurons. The resting potential of a neuron (-70mV) is maintained through differences in concentration and permeability of Na, K, and Cl ions. A graded potential is created as neurotransmitters from adjacent cells that are either excitatory or inhibitory. If the neuron reaches the threshold of -55mV an opening of voltage-gated sodium channels triggers an action potential that may affect other connected neurons.

PhET neuron simulation - https://phet.colorado.edu/en/simulati...

Music Attribution

Intro
Title: I4dsong_loop_main.wav
Artist: CosmicD
Link to sound: http://www.freesound.org/people/Cosmi...
Creative Commons Atribution License

Outro
Title: String Theory
Artist: Herman Jolly
http://sunsetvalley.bandcamp.com/trac...

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