Action Potential

Steps in Action Potential:

1. Cell in its normal state (polarized cell) called Resting state block Na+ ions.
2. So outside of Cell is positive wrt to inside. This potential is -70 mV
3. When cell is stimulated the cell membrane momentarily allows Na+ ions.
4. So inside of cell becomes positive (Depolarized cell). This is called action potential (20mV)
5. Immediately after effect of stimulation ceases Na+ ions are transported back outside (Repolarized cell).

Conduction of action potential is rapid in mylinated axons.

References:

1. http://outreach.mcb.harvard.edu/animations/actionpotential.swf
2. http://bcs.whfreeman.com/thelifewire/content/chp44/4402002.html