Thanks for making this helpful video! I wanted to clarify my understanding of the underlying physics so I would appreciate if you could correct any misconceptions I have. Statements such as "the chemical gradient pushes ions from regions of high concentration to low concentration" and "the electrical gradient pushes positive ions from regions of high positive charge to low positive charge" (paraphrasing) seem slightly imprecise (but I understand the didactic necessity for abstractions). It's not that there is a physical law that the chemical gradient pushes ions from regions of high concentration to low concentration but rather that, due to Brownian motion, it is more likely ON AVERAGE for particles to move in the direction of low particle concentration regions. Thus, the "force" exerted by the chemical gradient is just an emergent property of Brownian motion. It could happen by chance that a group of particles in one region move into a smaller region and become even more concentrated. But, over time, this situation is less likely to occur than diffusion. I would similarly press the abstraction of the electrical gradient exerting a "force" as well. Since the electromagnetic force extends infinitely (and decreases proportionally to 1/r^2), every charged particle exerts an electromagnetic force on every other charged particle (and this abstraction can be broken down further to the subatomic level but I don't think that's necessary for this topic). Thus, there is not an electrical gradient that pushes the K+ ions towards the other side of the membrane. Rather, as the concentration of K+ decreases in the bottom side (and the ratio of Cl- to K+ increases), there is, ON AVERAGE, a stronger electromagnetic force exerted on the top-side K+ ions toward the bottom side. But, this is not necessarily always the case. Let's imagine this situation: momentarily, due to Brownian motion, the remaining K+ ions in the bottom side moved right against the membrane (top of the bottom side) while the Cl- ions (all on the bottom side) moved to the bottom of the bottom side. At that moment, for any of the K+ ions in the top side, the y-component of the vector representing the summation of the forces of all the other molecules on that K+ ion would point away from the bottom side. When we say the electrical gradient "pushes" the K+ ions toward the bottom side it is rather that, on average (over time), the moment-to-moment average (over all the other ions) force exerted on each top side K+ ion points toward the bottom side (not directly toward it per se but I mean the summated forces vector's angle (where pointed exactly left = 0 radians and pointed exactly right = π radians) is more likely to be between π and 2π than 0 and π). I.e., much like the chemical gradient, the "force" exerted by the electrical gradient is an emergent property of many individual electromagnetic interactions. I just had the thought that perhaps the membrane has an effect on the electrical gradient somehow (negligibly?). Anyway, thank you for reading and I would love to hear any corrections to my understand of the underlying physics.
you're the BEST!! This is the most helpful way I have ever learned it and finally....got it :) I seriously love you, I watch you all the time when ever I need a bit more clearer explanation, keep it up, your making a difference, a huge difference!! :)
Something I think you should note is that when potassium is entering the cell in your example, the inside of the cell is potassium filled, (like is attracted to like), therefore it moves down it's concentration gradient (simple diffusion). If it were to enter a cell filled with hydrogen ions, it would require a channel protein and would move up it's concentration gradient because it's simply not attracted to the hydrogen ions. This is the electrochemical gradient...
characterize membrane needs permittivity, charge regulation with time, ion-ion, particle-membrane interactions only some membrane journals publish them numerical are few I suppose
*_...where does space, fit into your equations-when K⁺ gets across the membrane it's going to spread out (you implicated this already), but how far, does it go, equationally, and what-becomes of the chemical and electrical gradients and potentials near, far, and-farther..._*
*_...p.s. Why is, the Nernst Equation-it obviously doesn't work at quantum levels where a single atom has a chemical gradient to cross the membrane, but once across it has the same to go back-so it's not-really a 'gradient' but maybe a 'half-gradient',-and why log when log 1 = 0, and log 0 = -∞, for that one lone atom ('wee-haw, giddy-app')..._*
Thank you so much, i never quite understood the electrochemical gradient before watching this. However, something is confusing me. What's the difference between the equilibrium potential and the resting potential?
assuming the equilibrium potential of K+ is -90mV, the K+channels would open up to release more k+ions outside the cell in order to bring up the resting membrane potential of "-110mV" closer to -90mV.
Hey Mr. Anderson, do you know if Tyler Dewitt is ever going to come back and make Chemistry videos for us? Or does he have some other work outside of UA-cam he has to attend to?
Okay so I have been struggling with the fact that the overall concentration inside and outside the cell stays the same, bc of electrostatic force, yet if more ions leave/ enter the cell to reach their equilibrium potential, doesn't the concentration change at least for a short period of time? Like I get that it is pulled back into or out of the cell bc of electrostatic force, but still? I feel so dumb for not getting an intuition for this sorry
In the start I would like to thank you very very much for this great doing and secondly I would to ask you 2 questions because I did not know how to solve them the first is why when we sleep for hours under cover in the bed we donot die what is the cause please sir answer me I need your help and the 2 question depend on a photo but I didnot know how to send it for you thank you again
i love it when you talk science to me
we need thousands of you in our schools
Best teacher ever
He´s amazing! hands down
period
this video really helped me! the demonstration was simple and the commentary was very straightforward which really helps :)
you are the best teacher ive never had
The best teacher who made me love physics
This guy is awesome. Blows Kahn Academy away.
Racist
@@Bilbus7how tf?
@@hussnainali2738 he has a different point of view, its in his profile name
wIth full confusion from edx but now everything works out within 6 mins. Thank you so much
I'm a UPenn student and find your videos so helpful. Thank you!
Thanks for making this helpful video! I wanted to clarify my understanding of the underlying physics so I would appreciate if you could correct any misconceptions I have.
Statements such as "the chemical gradient pushes ions from regions of high concentration to low concentration" and "the electrical gradient pushes positive ions from regions of high positive charge to low positive charge" (paraphrasing) seem slightly imprecise (but I understand the didactic necessity for abstractions). It's not that there is a physical law that the chemical gradient pushes ions from regions of high concentration to low concentration but rather that, due to Brownian motion, it is more likely ON AVERAGE for particles to move in the direction of low particle concentration regions. Thus, the "force" exerted by the chemical gradient is just an emergent property of Brownian motion. It could happen by chance that a group of particles in one region move into a smaller region and become even more concentrated. But, over time, this situation is less likely to occur than diffusion.
I would similarly press the abstraction of the electrical gradient exerting a "force" as well. Since the electromagnetic force extends infinitely (and decreases proportionally to 1/r^2), every charged particle exerts an electromagnetic force on every other charged particle (and this abstraction can be broken down further to the subatomic level but I don't think that's necessary for this topic). Thus, there is not an electrical gradient that pushes the K+ ions towards the other side of the membrane. Rather, as the concentration of K+ decreases in the bottom side (and the ratio of Cl- to K+ increases), there is, ON AVERAGE, a stronger electromagnetic force exerted on the top-side K+ ions toward the bottom side. But, this is not necessarily always the case. Let's imagine this situation: momentarily, due to Brownian motion, the remaining K+ ions in the bottom side moved right against the membrane (top of the bottom side) while the Cl- ions (all on the bottom side) moved to the bottom of the bottom side. At that moment, for any of the K+ ions in the top side, the y-component of the vector representing the summation of the forces of all the other molecules on that K+ ion would point away from the bottom side. When we say the electrical gradient "pushes" the K+ ions toward the bottom side it is rather that, on average (over time), the moment-to-moment average (over all the other ions) force exerted on each top side K+ ion points toward the bottom side (not directly toward it per se but I mean the summated forces vector's angle (where pointed exactly left = 0 radians and pointed exactly right = π radians) is more likely to be between π and 2π than 0 and π). I.e., much like the chemical gradient, the "force" exerted by the electrical gradient is an emergent property of many individual electromagnetic interactions.
I just had the thought that perhaps the membrane has an effect on the electrical gradient somehow (negligibly?). Anyway, thank you for reading and I would love to hear any corrections to my understand of the underlying physics.
Best explanation I’ve ever been given 😮
Best video on youtube hands down, clear concise descriptions of mechanisms and how they function under differing environments...
I had the flu the day my professor was explaining this, this helped a bunch! I don't feel so behind anymore.
Why can UA-cam videos from 5+ years ago always explain concepts so much better than my current professor.......
Apparently my skull is quite thick, but that was refreshingly understandable. No matter how old you get science never stops being interesting.
Mr. Anderson, you're the best! We watch your videos all the time in biology and chemistry!
Thank you! I've been confused by this concept since grade 12 and I'm in my second year of uni right now
Thanks for explaining tough topics in simple words.... was helpful
This is the best site. Finally I found!
thank you so much! it is the best explanation I've got so far about electrochemical gradient
you're the BEST!! This is the most helpful way I have ever learned it and finally....got it :) I seriously love you, I watch you all the time when ever I need a bit more clearer explanation, keep it up, your making a difference, a huge difference!! :)
Thaks!!!! from Chile!!!
Sir please make a human physiology playlist. That would be amazing with you style of teaching.
thank you.
you explained this so well, thank you for making this video
Thank you for the explanation, I finally got it, best ever!!!!❤️
This was so helpful. So well explained and clear. Thank you
I LIKE WHAT YOU GOT. GOOD JOB.
Thank you so much for this, It was really helpful
Something I think you should note is that when potassium is entering the cell in your example, the inside of the cell is potassium filled, (like is attracted to like), therefore it moves down it's concentration gradient (simple diffusion). If it were to enter a cell filled with hydrogen ions, it would require a channel protein and would move up it's concentration gradient because it's simply not attracted to the hydrogen ions. This is the electrochemical gradient...
Amazing video! Thanks a ton!!!
This was so helpful, thanks!
characterize membrane needs permittivity, charge regulation with time, ion-ion, particle-membrane interactions only some membrane journals publish them numerical are few I suppose
Thank you. Great explanation.
Thank you for all your work!!
This is great, really helped, Thank you!
thanks really! best demonstration
Very helpful. Thank you!!
Fantastic , thank you 🙏
Excellent explanation
Wow! Thank you so much for this!
woow! great , thank you very much 🌸
*_...where does space, fit into your equations-when K⁺ gets across the membrane it's going to spread out (you implicated this already), but how far, does it go, equationally, and what-becomes of the chemical and electrical gradients and potentials near, far, and-farther..._*
i am an Mpharm student that was helpfull such a legend
thanks! that was really helpful; nice animations
That was very helpful, thanks alot
HOT DANG! Finally makes sense 🙌
*_...p.s. Why is, the Nernst Equation-it obviously doesn't work at quantum levels where a single atom has a chemical gradient to cross the membrane, but once across it has the same to go back-so it's not-really a 'gradient' but maybe a 'half-gradient',-and why log when log 1 = 0, and log 0 = -∞, for that one lone atom ('wee-haw, giddy-app')..._*
Nice presentation 👌
the best one in the whole world
not just help... it was awesome
I’m confused as to why it’s 37/13 are we supposed to know how many on each side exactly or just a general ratio
Thank you so much, i never quite understood the electrochemical gradient before watching this. However, something is confusing me. What's the difference between the equilibrium potential and the resting potential?
thanks m8 u explain pretty good
how does that sand that dosent get wet in water work?
Thanks a looooooot .best explanation
this is very helpful thank u sm
mind BLOWN
When is an electrostatic gradient the strongest during the change in a neuron membrane potential?
That was so useful.
That was helpful, thanks!
does water molecules enter cells by electrochemical gradient?
Thankyou Sir really helpful.
fantastic, even I understood this
If the cell membrane were hyperpolarized to a resting potential of -110 mV, what would be the effect on the potential opening of K+ channel?
assuming the equilibrium potential of K+ is -90mV, the K+channels would open up to release more k+ions outside the cell in order to bring up the resting membrane potential of "-110mV" closer to -90mV.
Hey Mr. Anderson, do you know if Tyler Dewitt is ever going to come back and make Chemistry videos for us? Or does he have some other work outside of UA-cam he has to attend to?
Love your work sir! Can you upload a video on Krebs Cycle please?
nice video!
Thanks a lot
very helpful
you are great 💜
Yes that was very helpful
Okay so I have been struggling with the fact that the overall concentration inside and outside the cell stays the same, bc of electrostatic force, yet if more ions leave/ enter the cell to reach their equilibrium potential, doesn't the concentration change at least for a short period of time? Like I get that it is pulled back into or out of the cell bc of electrostatic force, but still? I feel so dumb for not getting an intuition for this sorry
It was thank you very much 👍
Hey could you try this software? Pin Point: 'Circuit Solver' by Phasor Systems on Google Play.
Very nice
How can we have potential when all fluid compartments are electroneutral(anions= cations) ? Can anyone help!! So confusing
thank you.
Please I have multiple equations if possible to help me
You are amazing
Thank you
Thank u so much
thank you so much!!
Thank you !
thank you so muchhhh
In the start I would like to thank you very very much for this great doing and secondly I would to ask you 2 questions because I did not know how to solve them the first is why when we sleep for hours under cover in the bed we donot die what is the cause please sir answer me I need your help and the 2 question depend on a photo but I didnot know how to send it for you
thank you again
do you still alive?
I could've saved myself the past 2 hrs of staring at my professor's slides (and still being confused) by just watching this 5 min. video. 🤦♀️
GREAT!!!
Thank youuuuu!!!!!!!!!
thanks !
it's awesome
It's helpful
perfect
thanks you
legend
hi bozeman!
why can't the chloride pass through
fuck it up man thank you for this
really dont know how to thank u !
Thank you!!!!!! I actually get it lmao
synapse!
+Puffers Paradise coming soon
Hi
Noice