Med school student here who wanted to clarify some past comments. This is a solid, basic video to understand countercurrent MULTIPLICATION w/ your typical cortical nephron. Most of the negative comments coming from people who were probably looking for an explanation about countercurrent EXCHANGE which is a DIFFERENT passive process dealing with the vasa recta and juxtamedullary nephrons
It may sound corny but you also have a very pleasant voice as well as tone. So it makes it even better to listen to your very precise and well presented videos. thank you
i just spent the past couple hours watching all of the excretory/urinary system videos. so clear and detailed. just wanted to say thank you!! they are very helpful and just gave me such a more clear understanding of this system!! :)
the descending and ascending loops have different permeability. The ascending allows for solutes to move out into the the medulla space which, in turn pulls (through osmotic pressure) water from the descending tubule. This causes the filtrate to become more concentrated as is moves down the loop and less concentrated as it moves back up. This is all happening while the filtrate is moving so it has a multiplying effect. Hope this explains somewhat.
Joel V George, the concentration of the solute decreases as it moves up the ascending limb because solutes such as Na, Cl, K, are removed from the fltrate via active transport
i just want to say thank you, i had such a hard time in my anatomy class understanding the physiology of the nephron loop, you explained it well! thanks again
The juxtaglomerular apparatus ( Macula densa) forms when the " thick portion of the ascending limb of Henle" passes through the vascular pore, not the distal convoluted tubule, because the distal comes actually after the macula densa. This video gives a nice overview of the nephron tubules, even when it doesnt really expalins the countercurrent multiplication.
This was an absolutely beautiful video. I have scoured the web looking for information about the urinary system and this was the absolute best! Thanks again.
I must respect Khan Academy ....They explain detailed topics In such a simple manner and I thought tht these Topics were too Hard to grasp it😢..I would donate to khan academy
The only advice I would give on this video is to add the significant hormones that cause reabsorption in different parts of the nephron. That way, students can pull in the endocrine system and get a better understanding of how the renal, endocrine and cardiovascular system all connect. That would be more of MCAT style thinking... But great video.
+Amanda Strong Yes, completely agree! Hormones are so heavily involved in maintaining homeostasis. Would be beneficial to hear about renin, aldosterone, etc.
thank you very much Khan Academy..... what is being explained here is just what our lecturer teaches us, I am starting to think that maybe our lecturer watches your videos before they come to teach us.
this video is so impressive. my friend's father is suffering from kidney failure. He also took dialysis. I told him about Dr. Vikram Chauhan. He took treatment from DR. Vikram now his health is much better.
I've watched several of your videos and I am so impressed. I'm thankful for the simple explanations of what can be complex subjects. Fantastic teacher!
You're incredible- thank you! remembering the names is the hardest part, the repetition and explanation of why things get their names e.g. proximal convoluted tubule is so helpful! Thanks!!
Good overview. My understanding of the vascular support of the nephron is different however. I understood that the afferent arteriole split into 2 vessels, the peritubular capillary and the vasa recta. The peritubular capillaries are localised to the cortex, where they take up solutes and water reabsorbed by the PCT and DCT. Most of renal plasma flow passes through these vessels. However a small proportion of the blood from the afferent arteriole is sent to the medulla in vessels known as vasa recta, in order to take up the solute and water reabsorbed by the loop of Henle. This is important as the generalized vascular support structure illustrated in the video above would quickly dilute the medullary interstitium (as the salty interstitium would draw water out of these vessels). Hence blood supply to the medulla is necessarily poor.
Thank you so much! I initially got confused with what you mean by reasorbed. Either you talk about being reasorbed by the tubules or the body. But, I get it now. So thank you so much!
Nicely done! However i read in Junquiera's Basic Histology that 65 % of the water is reabsorbed in the proximal tubule. Almost 100 % of the glucose, the vitamins, the small proteins and the aminoacids get reabsorbed. About 85 % of the ions as well.
The loop of Henle is now called the Nephron loop. at least thats what they are teaching in universities now. But this is a brilliant video I finally got my head around this system
The arrows with respect to the term "reabsorption" is confusing me at 5:23... I thought the ions will get reabsorbed into the blood (not tubular secretion which is what the arrows show in the video here).
Leena Rani no I was thinking the same thing and it’s at 4:23 not 5:23. In reabsorption, solutes move from the filtrate to the blood as opposed to the blood from filtrate seen in filtration and secretion
I do have to admit, I love your videos, but this needed to focus more on the counter-current. the balance.
Med school student here who wanted to clarify some past comments. This is a solid, basic video to understand countercurrent MULTIPLICATION w/ your typical cortical nephron. Most of the negative comments coming from people who were probably looking for an explanation about countercurrent EXCHANGE which is a DIFFERENT passive process dealing with the vasa recta and juxtamedullary nephrons
super late here, but bless this is the most helpful comment I've read in my history of RUclips
It may sound corny but you also have a very pleasant voice as well as tone. So it makes it even better to listen to your very precise and well presented videos.
thank you
Does he not sound like Justin Long?!
i have eargasm listening to this silky smooth voice
😊😂😅😅
i just spent the past couple hours watching all of the excretory/urinary system videos. so clear and detailed. just wanted to say thank you!! they are very helpful and just gave me such a more clear understanding of this system!! :)
theres no actual explanation on countercurrent mechanism here at all......
thank you for saving me some time
the descending and ascending loops have different permeability. The ascending allows for solutes to move out into the the medulla space which, in turn pulls (through osmotic pressure) water from the descending tubule. This causes the filtrate to become more concentrated as is moves down the loop and less concentrated as it moves back up. This is all happening while the filtrate is moving so it has a multiplying effect. Hope this explains somewhat.
sure was waiting for something like that.... thank you
why does the concentration of filtrate decrease as it moves up the ascending limb of the loop of henle though?
Joel V George, the concentration of the solute decreases as it moves up the ascending limb because solutes such as Na, Cl, K, are removed from the fltrate via active transport
i just want to say thank you, i had such a hard time in my anatomy class understanding the physiology of the nephron loop, you explained it well! thanks again
TY for saving me from mild panic while I tried to make heads or tails of this thing for my exam.
Saved me at least 5 minutes of internal sobbing
Of all Khan's video lectures ... This guys are the very best!! To the guy who facilitated this video, Thanks for being so awesome at teaching.
I'm so attracted to your hand writing
you should call it click writing
Genius, you managed to explain me what the profs at university couldn't. Big compliment for your work, I really appreciate it!
The juxtaglomerular apparatus ( Macula densa) forms when the " thick portion of the ascending limb of Henle" passes through the vascular pore, not the distal convoluted tubule, because the distal comes actually after the macula densa.
This video gives a nice overview of the nephron tubules, even when it doesnt really expalins the countercurrent multiplication.
One of the most helpful science videos that I've watched! My teacher will be asking about countercurrent multiplication today - now I'll be ready.
Taught this better than my teacher
+Anchor BRO OR....he's just a bad teacher who isnt very good at teaching lesson so that it's easily understood *sigh*
+SlimTribe Tell me about it. My teacher basically ends up confusing us more....tsk tsk.
My comparativ anatomy exam is tommorrow, and thanks to this video I finally get the freaking nephron! Yay, thank you!
+TheHappyTears goodluck
only the best works at khan's academy. i have so much respect for mr khan for hiring only the very best.
really need to include the vasa recta, which is where the actual "multiplication" comes from.
agreed
exactly!
isn't it that at vasa recta countercurrent exchange happen not multiplication
Exactly
I was having a hard time trying to understand the counter-current mechanism, but this video made it crystal clear. Thanks a lot!
This was an absolutely beautiful video. I have scoured the web looking for information about the urinary system and this was the absolute best! Thanks again.
Thanks so much for helping me study for my bio IB exam!
The title is a misconception. I was waiting for the countercurrent mechanism explanation
I must respect Khan Academy ....They explain detailed topics In such a simple manner and I thought tht these Topics were too Hard to grasp it😢..I would donate to khan academy
The only advice I would give on this video is to add the significant hormones that cause reabsorption in different parts of the nephron. That way, students can pull in the endocrine system and get a better understanding of how the renal, endocrine and cardiovascular system all connect. That would be more of MCAT style thinking... But great video.
+Amanda Strong Yes, completely agree! Hormones are so heavily involved in maintaining homeostasis. Would be beneficial to hear about renin, aldosterone, etc.
This is very well explained. Best I’ve seen on RUclips. By the way I teach A&P so I know what I’m talking about
thank you very much Khan Academy..... what is being explained here is just what our lecturer teaches us, I am starting to think that maybe our lecturer watches your videos before they come to teach us.
this video is so impressive. my friend's father is suffering from kidney failure. He also took dialysis. I told him about Dr. Vikram Chauhan. He took treatment from DR. Vikram now his health is much better.
I've watched several of your videos and I am so impressed. I'm thankful for the simple explanations of what can be complex subjects. Fantastic teacher!
If only I had seen this earlier.... It's really well explained!!
You're incredible- thank you! remembering the names is the hardest part, the repetition and explanation of why things get their names e.g. proximal convoluted tubule is so helpful! Thanks!!
Good overview. My understanding of the vascular support of the nephron is different however. I understood that the afferent arteriole split into 2 vessels, the peritubular capillary and the vasa recta. The peritubular capillaries are localised to the cortex, where they take up solutes and water reabsorbed by the PCT and DCT. Most of renal plasma flow passes through these vessels. However a small proportion of the blood from the afferent arteriole is sent to the medulla in vessels known as vasa recta, in order to take up the solute and water reabsorbed by the loop of Henle. This is important as the generalized vascular support structure illustrated in the video above would quickly dilute the medullary interstitium (as the salty interstitium would draw water out of these vessels). Hence blood supply to the medulla is necessarily poor.
I absolutely adore your handwriting!
Excellente video and thank you!! 💚
This is such a good video, thank you very much. I could listen to you all day bro.
Thank you so much! You made learning for my test so much easy! :)
THIS WAS BEAUTIFULLY EXPLAINED. THANK YOU!!!!
3:55 correction:thin descending loop of Henle isn't completely impermeable to ion. It can reabsorb some Sodium ion.
Such a great video with what I need to know for my final. Thank you!
Great explanation! It really helped! Thanks Khan Academy ..
That was the best explanation I found on youtube so far!!
This helped more than any other video's i've found. THANKYOU :D
Wow beautiful explanation. Thank You Sir.
Your handwriting is beautiful :)
Thank you for your videos as well :P
Thank you so much! I initially got confused with what you mean by reasorbed. Either you talk about being reasorbed by the tubules or the body. But, I get it now. So thank you so much!
thank you. i am taking my ap bio test in 2 days. the book doesn't make sense to me but this video saved me. THANK YOU
Wow these videos are well explained and are super clear!! Thank you KHAN ACADEMY 🙏💕
This is a great breakdown of how this works, thank you!
Excellent video, Conceptually very clear...
The Afferent Arterioles branch off from the Interlobular Arteries not directly from the Renal Artery
I can't even tell you how much your video's have helped me. Thank you, thank you, thank you. :'(
This video is great! Thank you so much! made it super easy to understand! ^.^
Amazing and very well explained videos .
Extremely helpfull for students
fantastic video, great programme and so interactive. Brilliant teaching method and delivery with your speech. HD.
Thank you!!
Such a fantastic and well explained video! THANK YOU!!!
I finally understand all of it! Thank you!
Are you Enrique Iglesias? Because you're my hero.
Easy to understand the concept.good
Khan academy coming in clutch 🙏
Very helpful!
great explanation, really like it, thanks a lot!
Thank you so much, your explanation was great.
Thnk God finally I have counter current mechanism
Thank you so much!!! your videos really help me to understand all concepts
your explanation is amazing
Wonderful explanation!
oh god I was like trying to understand it from 2 days from my textbook but it just took 10 mins to understand all this stuff thanks a lot
You're great!!!! Thanks for sharing your knowledge!!!!
I can't never understand like this thank you sooooooooomuch really thanks
Really Helpful!! Thank You
awesome explanation sir...thank you
Great handwriting and explanation!
Nicely done! However i read in Junquiera's Basic Histology that 65 % of the water is reabsorbed in the proximal tubule. Almost 100 % of the glucose, the vitamins, the small proteins and the aminoacids get reabsorbed. About 85 % of the ions as well.
So helpful. Thanks a lot.
The loop of Henle is now called the Nephron loop. at least thats what they are teaching in universities now. But this is a brilliant video I finally got my head around this system
Thank you so much for the explanation. 😁
Great really thanks 😄
Thank you so much!
Thanks a lot, really nice video...
nice video .helped me a lot
subscribed: checked! So glad I found your channel, your explanations are extremely helpful and detailed!
Amazingly helpful!
Thanks for that great information!!!
The thin segment of ascending limb should be facilitated diffusion while the thick segment of ascending limb carried out active transport
Amazing!!!!
Very good stuff man
helps me a lot
Fantastic ..♡
I LOVE YOU FOR THIS VIDEO!
Nicely described❤
Awesome man.
Thank you, really helps :)
I want to share a scientific kiss with this man
sobster123 HAHAHAHAH
😂😂😂
I like his handwriting!!
thank you sir !!
I am your big fan sir🥺🥺✨❤️
Thanks!
The reabsorption arrows for Na and Cl ions are confusing in ascending limb. Besides that it's a good explanation. Thank you.
Great jobb!!
thank you sooo much
The arrows with respect to the term "reabsorption" is confusing me at 5:23... I thought the ions will get reabsorbed into the blood (not tubular secretion which is what the arrows show in the video here).
Leena Rani Wait. Nevermind. I got it.
Leena Rani no I was thinking the same thing and it’s at 4:23 not 5:23. In reabsorption, solutes move from the filtrate to the blood as opposed to the blood from filtrate seen in filtration and secretion
LOL to be peed away. Thanks for this video it helped a lot!
Thanks again
good explanation skills. (y)