Action potential nervous system

Action potentials are brief, rapid, large changes in the membrane potential in which the potential actually reverses. They are usually initiated as a result of spread from graded potentials. Simil…

Propagated action potential is the nerve impulse

“Maintenance of resting membrane potential. The action of Na+/K+ ATPase, Na+ leak channels, and K+ leak channels creates and maintains a resting membrane potential of -70mV” until threshold is reached at ~-55 to -40 mV.

Post 2 in the Crash Course series on how the nervous system works: Action Potential! Neurons are extraordinary cells. Beyond being intricately branched and gigantic relative to most cells, every second hundreds of billions of electrical impulses called action potentials are transmitted in your body. Before we check out how that works, it's useful to…

http://hyperphysics.phy-astr.gsu.edu/hbase/biology/imgbio/actpot4.gif

This image displays an action potential traveling down the axon. In the place of the action potential, the membrane potential is the opposite sign as the rest of the membrane, and it is followed my a refractory period, so the potential is one directional.

Depolarization across cell membrane to threshold level leads to generation of action potential via opening of voltage gated Na+ channels (close before threshold and after reaching +35 mV) and influx of Na+ due to electrochemical gradient, followed by repolarization via opening of positive charge activated voltage gated K+ channels and efflux of K+ out of interior due to electrochem. grad. wanting to restore internal negativity and hyperpolarization before returning to resting membrane…