Videos

generation of AP

Added Jan 12, 2016 •

Copy this URL:
Embed code:	<iframe class="edlio-embed-player" type="text/html" width="640" height="360" src="//jhs.jisd.org/apps/embed/?v=100227" frameborder="0" allowfullscreen></iframe> Change dimensions

Show Transcript

neurons send signals over long distances by generating and propagating action potentials  most action potentials originate near the axon hillock of the cell body in the initial segment of the Axon then travels the entire length of the accent a closer look reveals that during an action cancel  voltage gated channels open and close altering the permeability of the plasma membrane to sodium and potassium a threshold stimulus changes the shape of the voltage-gated sodium channels they're activation gates to open this event marks the beginning of phase 1 of the action potential known as depolarization does sodium ions diffuse into the axon the membrane potential becomes less negative  this is More Voltage gated sodium channels to open and the membrane potential stores to 30 millivolts  at this point key events occur the inactivation Gates of voltage-gated sodium channels close and voltage-gated potassium channels open these two events Martha beginning of phase 2 of the action potential known as repolarization  Espetus ions diffuse out of the axon the membrane potential becomes a negative again however the membrane potential continues in the negative erection going beyond the resting state of -70 millivolts this marks the beginning of phase 3 of the action potential known as hyperpolarization during this phase voltage gated potassium channels close and voltage gated sodium are released from inactivation by the end of this phase ions move through the channels and the membrane potential returns to the resting of -70 millivolts the new run is now ready to fire another action potential summary generation of an action potential gated sodium channels sodium ions diffuse into the axon depolarizing It 2 + 30 millivolts voltage-gated sodium channels close and voltage-gated potassium channels open  potassium ions diffuse out axon reprising it to a negative value the membrane potential Reedley hyperpolarizes voltage-gated channels close and the Brain returns to the resting state of -70 millivolts

Uploaded by Jan Gowin.

Videos

generation of AP

More videos from Jan Gowin