Neuron action potential description | Nervous system physiology | NCLEX-RN | Khan Academy

Created by Matthew Barry Jensen.
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[@AspidSnake]

KZbin teachers>>>>>>>>>>>>>>>>College teachers

[@supernaturalswampaids8083]

Omg...I love that feeling you get when you finally understand something you've thought about before! This video gave me that "ah ha!" moment just now. Imagining the amount of neurons firing in a human brain gives me the same wonder as thinking about the stars and universes. How "simple" actions/causes can turn into fully functioning creatures and solar systems. Physics = life/love

[@Ureyeuh]

The fact that I can access this level of education anywhere that I have cellular service astounds me. This was so insanely educational and I am just in awe of the ability to obtain this knowledge.

[@bsedakrkmaz]

I can understand chapters better after watching khan academy videos. Studying from textbook is not effective like that. Thanks a lot ! :)

[@RyanRafferson]

Ive been taught that resting potential is -70mV and the refractory period in action potential begins at -80mV. Also it would have been nice if your described why action potential is faster through the myelinated sheath

[@Arsh.99]

+Ryan Patterson The way an action potential propagates is by opening voltage-gated sodium channels which depolarize the cell. Think about how long it would take to conduct an action potential if you had to open channels along the entire length of the axon and wait for sodium influx. In the case of the myelinated nerve fibers, the myelin sheath covers large portions of the axon, leaving uncovered spaces known as nodes of Ranvier. The sodium channels in a myleinated nerve fiber are only at the nodes of Ranvier. So one sodium channel opening depolarizes a much greater length of the axon until it reaches the next node of Ranvier, where the voltage-gated sodium channels open and this cycle continues. In essence the AP "hops" around, covering much greater distance in a shorter amount of time.

[@mishaarya3786]

In simple words action potential jumps through node of ranvier in myelinated sheath and that's faster

[@adisatiara]

I've been cramming myself up the whole night until daylight comes for my biopsychology exam and my pea brain still can't get it, so I had to look it up on youtube AND JUST FROM 6 MINS OF THIS VIDEO I GOT AN A. Thank you very much

[@NadiZombieChu]

Many people complain that it goes very fast, but I'm a medical student myself and currently learning about this subject. I can follow along easily and I understand it a lot better now thanks to this! I don't think people should just watch these video's and only learn from them, but people should use this as an extra help along with their studybooks/etc. But what I really wanted to say... Thank you for this video!

[@HT-rq5pi]

+camilo sanchez lol.

[@SunSunSunn]

Wtf? All the people I know watch this on 2x speed

[@InVivoRL]

Dude im in grade 12, thats whys it's fast for some people, because you don't just learn this in med school. I watch this at 1.5x because hes actually kinda slow but some people are learning of this.

[@raphro3845]

Rebecca CRNA The terminology he uses is explained in previous videos. If anyone is having similar problems (which judging by the upvotes on your comment appears to be the case) I recommend watching the previous videos, they're fantastic. The playlist is linked in the description.

[@rebeccasigler6986]

I feel like I am just reading a difficult text when listening to these videos on neurotransmitters, etc. It doesn't sound like an explanation, but rather like a fast reading from a text. It would be great if you could clarify some of the terminology as you go along, like around :50 with all the potentials, it is extremely difficult to follow and your speech is very quick as well. I believe most people wanting to learn this would appreciate it being "dumbed down" more!

[@michelleolson8932]

Thank you for helping me pass my physiology course!

[@aftermath7]

6 minutes 53 seconds well invested...👍

[@Soulanguish]

Thanks for this, my college cell biology book explains this awfully.

[@ln9480]

Thanks khan. I'm trying to take an online course in this, and your videos are much, much clearer than the provided instruction.

[@toekneesee]

Your voltages are different from any other source I've ever come across, previously it's always been about -70v for resting potential and the threshold lays at about -55v. However, I didn't know that axon width increased size so thanks for that x

[@abeershaath3720]

i was totally lost with this. and now its all clear. thank u so much

[@marcussmith4913]

sweet jesus this video gives me nightmares of classes long since completed.

[@Swiddler]

and what does the neuron fire? ions of some kind? neurotransmitters?

[@AndroidOO3]

Love your voice. Reminds me of John Michael Higgins. Wish you would have used more terms at some point.

[@missmadamx3]

What happens when the sodium potassium pump is inhibited (by a drug or something)? Does depolarisation or hyperpolarisation occur?

[@ayeshasaleh8669]

I finally understandddd

[@leenshahin9942]

what app do you use to make your videos?

[@barnseymedia]

This is brilliant. Thank you! I learned the resting potential is -65mV. So im seeing variations, but they all seem to be very close. Is it possible that it mildly varies from person to person?

[@abdullahmohammad6803]

im told the resting potentisl is -70 mV

[@josepaul2000]

When you say a voltage, what is this voltage with respect to? (Which 2 points?) The average voltage in the encompassing area or something?

[@richardaversa7128]

Inside vs outside membrane.

[@AnimeFriendship]

Thank you!truly

[@koolbeans7598]

Thanks

[@sakibmahmud7196]

I have a question. when we enter the excirory ions means positive ions, the membrane potential should be decrease cause it balance between two side. but in graph why we then elevate the potential as that it incraeses and vice versa?

[@absm6794]

+Sakib Mahmud elevated potential because the relative potential increases because it becomes more positive (or less negative) as the positive excitatory ions enter. Positive ions raise membrane potential relative to baseline or resting potential.

[@sakibmahmud7196]

thanks bro

[@bussychan]

I wish we had youtube circa 2003!

[@LEMONMANIZATION]

I find it interesting how Fish have positively charged sodium in their blood which separates the Oxygen from water. I wander if neurons do the same thing to get oxygen from the capillaries.

[@IronTom]

y is it more more negative inside the membrane? is it due to negatively charged proteins?

[@jennifercano700]

It is due to the sodium-potassium pump in order to maintain the concentration gradient. There are higher concentrations of sodium outside of the cell and lower concentrations of potassium inside of the cell (along with other negatively charged ions).

[@IronTom]

Jennifer Cano i revisited different video and now i understand its because higher number of sodium os pumped to the outside (3) - less potassium pumped to the inside (2) so that creates the difference because there is higher number of positively charged particles on the outside. As you said higher concentration of positive charged sodium creating greater positivity where on inside is more negative. And I guess also the other negative particles inside create the difference. I think i got it now.

[@janerosiecurran]

It is due to the permeability of the membrane to potassium. This means that potassium can diffuse down its concentration gradient out of the cell but this can only carry on for a certain amount because by diffusing out, the potassium ions create a negative potential on the inside of the cell which prevents more positively charged potassium ions from leaving

[@huniverso]

Great

[@LegendInTheMaking11]

Surviving college bio

[@blancasanchez5474]

:

[@diyaathanki2346]

any timchanko fans

[@cameronashley2681]

am i the only one who didnt get it the first time

[@SuperCoppercab]

this guy isnt as cool as the salmon kan guy lol

[@tenochtitilian]

Not as enthusiastic but still a fantastic explanation.