Myelination and Saltatory Conduction

[am.d]

The best and clearest lecture series I have seen on youtube.

[davidvalle]

Im a EE studying for the MCAT, cant believe he started this video with current trhough a wire. The more I study the life sceinces, the more I'm certain that our bodies are an engineering masterpiece

[smeetdesai]

i was looking for a good explanation regarding saltatory conduction, absolutely loved your brief and crisp revision. keep up the good work maestro!

[willy]

Outstanding lectures, sir. Thank you so much.

[hajar]

Thanks a million for this great explanation!

[purpleriver]

super explaination. Very well organized that make it easy to remember. Thank you!

[sam]

Could someone help me understand why the axon has to be "insulated", rather than just having nodes that are the same distance apart but without any myelin? I mean, why is myelin essential to this particular process? What would happen if there was no myelin between two nodes of Ranvier?

And I'm having a hard time understanding how the part about larger diameter --> less resistance is relevant. If the signal doesn't actually travel through the myelin, the myelin doesn't seem to do anything in this regard?

[drxersiosman]

Iam very glad to have such clear that make classified. which I understand alot of thing that I was ignorance person before it.THANK YOU VERY MUCH

[thetrdoctors]

Thank u...awesome explanation
But I have a simple question...
Does the nodes of ranveir contain potassium channels for repolirization that occurs after the action potential is moving away from this node to the next node??

[AmiraAshraf-iu]

First, I would like to thank you at all. But I have a question by using myelin sheath the speed nerve impulse transmission increases at the same time I think it makes the distance of transmission increases that means increasing of axolemma length but when length increases the speed should decrease so how these two points happened in addition they are antagonist to each other.

[lostinthoughts]

Great stuff, just great.
So in myelinated areas there are no action potentials but simply positive ions moving towards a node of ranvier, right ?

[dyoomah]

Thanks very much ☺ .. I have question does all the neurons in our body have a myelinated axons !! And all of them propagate by saltatory conduction ? OR there's neurons propagate by contiguous conduction ???

[barneystinson]

Hi MateI am struggling to find some information about physics perspectives of demyelination, could you please help out.

[mohamadekrama]

I have been struggeling to distinguish btwn abs and rel refractory never again

[oldhounddog]

I usually love your lectures but I think the analogy from electric current flow to the biological process of the saltatory conduction (SC) incomplete. My biochemistry book (among other sources) explains the SC action as the opening & closing of voltage-sensitive gated channels opening & closing allowing first the sodium ions to rush in forcing the potential to change to a more positive voltage which is shut off when positive enough triggering the potassium ions to move back into the cytosol causing the electronegativity to become very negative. The result is two-fold. Na ions diffuse toward the next node of Ranvier and a refractory effect prevents a backward stimulation along the axon. I strongly suspect from what i have studied while the analogy seems fundamentally to explain the process that upon deeper examination the biological process just does not follow the physics of current flow in a wire. When comparing the large diameter axon of a squid to that of a typical human nerve cell does the analogy hold up? The speed of propagation is relatively the same but is the process the same? If I am sick the cause of the symptom may not be the same as the symptom in someone else. I still need to find the chemical structure of myelin!

[wenxilau]

May i know what is local circuit neurone ??

[xtrem]

I like my women like I like my axons



Short and thick