Electron Transport Chain
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- Опубликовано: 30 сен 2024
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Overview of the Electron Transport Chain
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imagine taking a semester class with this guy as your biology professor. Would actually be worth paying tuition.
Yeah I know @Andrea Gallegos
I am in an introductory Microbiology class and I cannot explain to you how much all of these videos have helped me. I DEEPLY appreciate you taking the time for this because I feel prepared for my test now when I thought all hope was lost. THANK YOU SO MUCH!
Very good! A new fact is that each NADH gives 2,5 ATP, and each FAD2 1,5 ATP. This is the reason some books teach that one glukos gives 38 ATP, och and some say it only gives 30-32. The books stating 38 ATP are using old data and are wrong.
How did people survive without Khan academy before Sal invented it??
Where does the oxidation and reduction takes place? And What is a respiratory chain?
I don't normally comment, but holy shit Khan Academy thank you so much.
agreed
newer concept states:
1 NADH provides 2.5 ATP
1 FADH2 provides 1.5 ATP
therefore by the end of cellular respiration 32 ATPs are formed
how .5? i have never seen that anywhere else?
Muhammad Usama 10 H+ are transported out of the matrix per 2e- passed from NADH to O2 through the ETC, and 4H+ are transported into the matrix per ATP then the mitochondrial P/O ratio is 10/4 or 2.5. For succinate, it's 6/4 or 1.5. The P/O ratio is the number of ATP molecules formed in the ETC per electron pair.
(From my textbook, Biochemistry by Garrett & Grisham)
Yes sometimes 32 sometimes 30 ATP.
@@calskankz2267 yeah depending upon the shuttle system operated.
@@prabhasingh5064 Can I ask you a question please? English is my foreign language.
In what cases is the word "upon" used in sentences?
Thank you!! I love these videos; they help so much! Khan academy is more useful than my $300 textbook
You are talking about Devlin's biochemistry, am I right? Thia book is so detailed you can't even comprehend what topic you are studying.
You do realize this is elementary level?
YoU dO rEaLiZe ThIs Is ElEmEnTaRy LeVel?
@@5327arod you got a problem ?
Futile Mortals it’s not elementary level tho it’s APbio
I agree. That's a classy "first". I am proud that Khan Academy viewers are this sophisticated :)
Khan Academy may we please get an app for khan academy please???
its just so surreal seeing comments from so long ago...13 years ago seems like a life time ago
THIS. NOW THIS is how a lecture should be taught. I'm so sick and tired of all my professors reading dully off of powerpoint slides. No explanation, no excitement, and it isn't even put in the lecturer's own words, making it harder to convey the full message. You have taught me ALL of the key points for aerobic catabolism when it took me 4-1 hour lectures and 3 hours of my own time reading through the book and sorting through all of the overwhelming information.
.Are there any plans underway to award Khan Academy a Nobel Prize or something.??just curious.
I'll sign that petition 🙋🙌
Google gave them hundreds of thousands of dollars to help out the program. I think that’s close enough lol
Well considering that Obummer got it for pretty much nothing, yes I think Khan should get it since he actually did something.
I like the enthusiasm, but no unfortunately
This takes "The mitochondria is the powerhouse of the cell" to a whole new level.
All those memes gave us an introduction
How in the world are you supposed to comprehend this in one sitting? It's like there is a component within a component within a component within a component within a component. And each one of those components has multiple pieces in of themselves. I lose context very quickly with each step being explained. You are very blessed with a good mind if you can understand all this in one sitting.
Jakigoto Wiga Everyone learns differently, and it's just really difficult for some people to understand the first time. Don't get me wrong, this video covers everything you need to know, but some may have to watch/analyze it more than once to understand it all.
Jakigoto Wiga Yes I agree! Okay, I was being a little serious; now I chuckle at your first comment (;
Well the purpose of this video is not to have you completely understand this by just watching the video. Most people learn this stuff in school first then watch these types of videos to solidify their understanding and make sure they know everything for a test.
This is complicated! Its why we teach it in college ex phys and biochem, and then again and again in grad school. If you're expecting to get it in the first run is unrealistic and doesn't reflect the difficulty of the topic.
its not that hard really... you should see the nervous system or immunity hahaha
Sal: i'm not gonna go into detail on this.
*goes in detail*
And the amazing thing, I understood it all
I remember watching this in AP biology in high school and now I'm taking biochemistry during my last summer of my biological sciences degree. Thanks Khan! You've been with me the whole time.
Nice video, slight correction: protons are pumped into the intermembrane space, they are not pumped into the outer membrane.
protons are pumped into the intermembrane space...but he named it outer space so the point is the same
Yo, i dont understand where the protons come from? I know they are pumped from the matrix to the intermembrane space. But where did the protons in the matrix come from.
+sjefenoversjef NADH is oxidized via the complexes(1,3, and 4) which releases the H from the electron carrier. So: NADH--> NAD+ and H+ are the products from oxidation.
Bob Marley Hmm..yes. I see! ty
Bob Marley So basically, every H+ that is pumped across the membrane comes from the oxidation of NADH?
im taking a biology test next week. thanks khan academy.
i sometimes regret i should rather have paid attention to professor than cram for an exam but i never put it into action :)
Amazing work.
Finally i understand what the hell they are talking about in class.
you should get a medal for that !
Thank you so much for these videos bro. I had my midterm this week over cellular respiration, photosynthesis, and cellular membranes. I read all the chapters in my textbook, but they were so complex I was having a hard time grasping it. Ended up watching your videos on each of these subjects all night before my exam and I got a 98! Almost half of the class failed the midterm and only 2 other people got As. You seriously explain things so well in a way that is very easy to grasp and remember. Thanks a ton
Me going through all these now and seeing your testimony just blow my mind🤯
I love it when he says "this is...THE CUTTING EDGE"
Sad times when you've used Khan academy since you were 14 for GCSE's, and now you can't because now you're doing a degree… :'(
It's worse not knowing about him until starting y13 A-levels....
Khan Academy is truly a life saver. This year when I embarked on my journey through AP biology I was really nervous because it's my first year of high school. However, by watching his videos and reading in my textbook I feel confident in my understanding of complex concepts and I have really come to love biology. Each day I'm one step closer to becoming a doctor ! Also, I'd just like to point out that khan academy isn't meant to give you the run down of an entire chapter in one 17 min video. It is essential that you read, listen in class, work on schoolwork at home, and then review. Ps: to the person who asked what the difference between chemiosmosis and the ETC is, chemiosmosis is the process of the atp synthase working within the electron transport chain. These two combined are known as oxidative phosphorylation. :))))
MoodiFLEX Im a ninth grader in Massachusetts. But the reason I'm learning it now is because I'm taking a college biology class (AP Bio )
grace Hamilton i actually knew this thing in my first year varsity
whats first year varsity? Mzwanele Nkunzi
grace Hamilton
I mean i knew it in my first year at university
MoodiFLEX thanks and thats really interesting i have always wondered how schools in different countries teach curriculum because here in america i think the general view is that you guys all go to private schools but maybe thats just how it is portrayed in movies and thats why i think that. are the majority of schools there private or public?
Before this video the ETC seemed so complicated- now after watching it I actually understand how it works! Khan's concise explanations really cleared up those 6 or so pages in my AP Bio textbook. Thanks Khan Academy for making biology so enjoyable and easy to understand!!
2e- + 2H+ + 1/2 O2 ----> H2O is the correct reaction..but you have wrongly shown it as 2e- + H+ + 1/2 O2 ---> H2O
+PRABAKARAN S omg that was driving me crazy as well.. ok yeah it's 2 H+s
+PRABAKARAN S He does say 2 H+, just wrote it incorrectly
in his next video of oxidative phosphorylation he corrects himself lol
This was driving me nuts. I had paused the video and was looking online for why 2e- + H+ gives you 2H. Thank you!
2 from glycolysis 2 from the oxidation of pyruvate and 6 from the Krebs cycle
idk about progress with researching ATP synthase but imagine how funny this will be when people actually find out how it works. i imagine grandchildren like: "they thought we had.. mechanically structured... motors? what were they on...''
how can i understand 17 mins video over 1 our lecture at college? KHAN ACADEMY YOU ARE MY SAVIOUR. My soul flew out of my body when you said the protons wants to go back in haha
Khan Academy saves my life every time it has to do with math or biology! This amazing video for ETC clarified many things for me. Basically a one on one session with a much knowledgeable person! Great job.
why can't you be my professor?
Who found Khan Academy?🤔
Khan Academy, you da real mvp.
I was under the assumption NADH = 2.5 ATP not 3....and FADH2 = 1.5 ATP not 2
Julia-Rose Satre Yup! You are right.
+Julia-Rose Satre this vid is almost 6 years old
it depends on which book you are using since every books has its own atps measurements.
+Julia-Rose Satre it's not exact. It's more like a range. 2-3 and 1-2. He just averaged it out.
nah cuz dat tings called aeteapee make like 38 of them shits yall know wat im sayin? like best case scinerio 38 shits, but normally like 29 of em shits is created yall know?
I know this was released year ago, but if your still around and getting notifications, can you tell me, where do the 2x ATP’s come from initially to start the process?. Do you have a video on this and do you have a video on how it works if you are a carnivore that doesn’t eat carbs(glucose)
You know, sometimes I feel like my bio teacher has no idea what he's doing. I just began watching these and I have already learned more than I have all quarter. Thank you very much and please keep producing these. I will definitely be coming back to them in the future.
Watched this video in my first semester of college for Bio 1, watching it again now in my last semester for biochemistry 2. Wow, glad I’ve made it such a long ways 😂
"Oil Rig"
O.I.L. R.I.G
Oxidation is Losing, Reduction is Gaining.
Took me a minute to figure out, as I have not watched whatever video that was explained in, Super glad I know now, really nice.
I love Khan Academy!! I wish the MCAT content doesn't get removed...I learn so much more from you all! :(
Very clear, and easy to understand! Thank you so much!!
***The formula of reduction, should be "2 H+"?
Jane Kuo
Yes i guess
Asked myself same thing
wow, this video came out when i was 7 years old and here i am in my first year of medical school watching it. crazy
This man is amazing! He has got to be one of the most innovative educators of our time! And just think of how many people he has taught in how many different subjects all over the world!!! Colleges and universities charge thousands to learn what he is giving for free... Someone give this man a Nobel Prize!!!
The net production of 38 ATP is correct for prokaryotes, but for eukaryotic cells, it is 36. Two NADH that were produced during glycolysis cannot cross the inner mitochondrial membrane and are therefore reduced. These molecules transfer electrons to an intermediate carrier molecule which delivers electrons to the second carrier molecule Q that you mentioned. This should mean that two NADH reduced from glycolysis produce 2 ATP yielding a total (with Kreb's and ETC) of 36 ATP.
great video! it helped me as review material for my National Board Dental Exam !
Sal 100% farted at 12:45. can anyone else confirm this with me?
I'm a sophomore in high school, and this really helped me solidify my understanding of this system for my AP Bio class! I'm going to have my teacher look at this! Thanks!
JandCandO Even I'm a sophmore and even I'm watching this video for my AP bio class. Actually, we have our bio final tomorrow so i'm just reviewing :)
you sir, will save my ass in my biology class. Im a freshman in college and am taking general biology at the University of Nebraska. My professor isn't the best and his wording and notes are confusing as hell. You on the other hand, should be given an award.
thanks man, much appreciated.
I love Miranda Sings.
@madej1858 the function of the ECT is to create a higher H+ gradient in the outer compartment. To reduce this gradient, the H+ then needs to get back into the matrix, and to do that they go through ATP synthase. As they pass through the ATP synthase, ADP and Pi are 'pushed' together to make ATP.
wow.. evolution...
the more i study biology, the harder it is for me to believe it.
You realize at this point, evolution is basically proven fact in the scientific community, right?
***** ?? yeah? what's your point? unfortunately it's a theory still.
shinviroz "A scientific theory summarizes a hypothesis or group of hypotheses that have been supported with repeated testing." This mean that "unfortunately", a theory is proven fact unless there is solid evidence to dispute it. The only real "evidence" to dispute evolution is religious examples which are not considered valid.
***** Yes I learned it as a theory back in highschool more than 10 years ago. I don't know how they teach it now.
***** cool, that's true. Are there any "real evidences" that disprove God?
there should be 2H+ in the reduction equation to balance out
at 5:29 just turn on the automatic English subtitles and you will see the magic :)
LOL so childish but it's funny
Great video. Very well explained. One thing that is bugging me is that ATP synthase does NOT use the energy from the proton gradient to directly make ATP. ADP and Pi readily form ATP once bound to the surface of the enzyme. The problem is that once they are bound and turned into ATP, it takes energy to get them off. THIS is what the gradient's energy is used for - popping the formed ATP off of the enzyme and allowing for another set of ADP and Pi to bind.
this is the most confusing thing ive ever watched
Awesome lecture. i just wished you would go more into detail on each of the complex's, heme's, cytochrome. but thanks a lot.. it gave me a good idea and for the other mechanism i was able to easily connect.
thanks Dr. Khan
This is proof that life itself is of intelligent design.
Aerobic respiration by itself is so complicated it doesn't seem to be a chance event.
A Bio Class is probably not the best place for Religious people to debate religion...
my A and P textbook in 2022 is claiming 36 ATPs: The ETC creates 34 ATPs and the Krebs cycle creates 2 ATPs.
Me too
I'm so dumb that even Khan Academy can't teach me this 😂
To think that all this shit happens when we take a breath and exhale....And we take everything for granted lol.
99% of the comments- thanking for video
You just saved my final :( listening to you for the first 5 minutes answered all of my confusion. Thank you so so much
One question : the hydrogen protons that are in the matrix that will eventually get pumped into the outer compartment . Are they the product of the oxidizing the NADH or were they already a part of the matrix ?
whoa
Not only is the ATP produced per NADH/FADH2 different in the US, there's no LEO the lion says GER, but an OIL RIG?
My brain is blown
SAL u rock! i'm studying for usmle step 1 and everytime i get stuck on the basic biochem stuffs I come back to your videos. keep up the great work!
apu eita amar kaje dibe... thank u
I'm beyond thankful that you added Arabic subtitles. I was thinking to drop the class but after I found your channel, hell nah I’m gonna take the class and I’ll try my best to take A+.
This is still helpful even after 10 years
Biology is awesome, thanks bro
اللي عربي ترى في ترجمة اليوتيوب باللغة نفسه (عربية ) حطوا لايك على شان يطلع فوق والناس تستفيد
طالب طب احبكم 😍😍
Where does the other H+ come from at the beginning, it is written that the oxidation of NADH produces two e- and 1 H+....slightly confusing as that would suggest the shedding of a H- ion? Yet it is written that 2e- + H+ + 1/2 02 -> H20?
oh my gosh I have a test over cellular respiration tomorrow and I just wasn't getting it but I watched a few of your vids THANK YOU SO MUCH
My dear friend Sal, What could I do without you?
Seriously this was the MOST fantastic description of glycolysis/krebs cycle/election transport chain/chemiosmotic coupling (the axel he described) that I have EVER heard! Your explanations were very clear, you did not include the additional details that were not required (these reactions that were skipped are relatively simple, but have a tendency to clutter all of these processes) to understand the process! Keep up the excellent work!
Hey yall! I was just wondering why when he was writing down the "last step of the ETC" why when he said there were 2 hydrogen atoms but never put the number 2 in front of the H when writing the equation? I suck at this stuff so any help is greatly appreciated!
Thank you, excellent explanation! Also relaxed :)
türkçe çeviride 6.50 de "bunda detaya girmeyeceğim" altyazı sonuna kadar devam ediyor
I just wanted to point out that it is actually 36 ATP formed at the end of the ETC. This is because the 2 NADH formed from glycolysis only produce 2 ATP in the ETC instead of the usual 3 ATP (on average). They are formed in the cytoplasm instead of the matrix so the electrons it puts forth toward to production of ATP are at a lower energy level, like FADH2, since they have go a further distance.
This is just what my professor explained to me.
Your videos are awesome by the way!!
finally im starting to grasp this ETC stuff! Thank you! I like his genuine excitement about it, it helps.
Great work. Reduction reaction not balanced properly. You are missing the second proton.
THANK YOU so much I saw your three lessons on Glycolysis, Kreb cycle, and Electron Transport chain and I completely understood everything. I am currently taking microbiology and when my professor was explaining it everything was confusing. Now with these videos I understand how ATP synthesis works. Thank You once again and keep doing videos because it is really helpful.
I've been taught that you're left with 8 NADH? 2 from the gylcolysis cycle and 3 from each cycle of the kreb cycle. so using two pyruvate wouldx equal 6..... 6+2 = 8. where is 10 coming from?
Khan academy ....you saved me from getting an F
thank you !!!!
Hi
Can I ask how many ATP molecules are produced in every ETC complex?
It was actually raised by our professor, according to him, every complex in the electron transport chain produces a particular amount of ATP..
He wants us to identify the ATP molecules produced in:
Complex I
Complex II
Complex III
Complex IV.
Thank you so much for those who can help☺️
where did the 10 NADHs at the beggining come from. Is it because you combined the two NADHs from glycolysis and the eight NADHs from the kreb cycle?
You don't actually get 10 NADH in the ETC per glucose. Each glycolytic NADH has to be converted into a glycerol phosphate to shuttle into the mitochondrial membrane where it ultimately reduces FADH. Thus, the video overestimates ATP production.
If you are looking for additional lecture notes on your University classes, or would like to upload your notes for cash, check out the extensive collection of notes on Oneclass.com.
P.S. Enter promo code"JPARK" on signup for 50 extra credits.
Is this still valid in 2019?
pretty sure...
As I understand it so far:
Basically, the energy contained in light moves matter (e-) around so you can do stuff (time). Without this energy your body does not-a-thing (no time). It would be dead. Or an in-between state would be sick.
Also the type of light, and lack thereof, is important, as it dictates what matter exactly moves around (signalling). Without proper signalling, life/structure declines more quickly than it would otherwise.
Once again, very impressive material for self study when your teacher just mindfucks you with confusion! How can anyone dislike this....250 aliens I guess.
tip: watch this on 1.25x speed to save time. It’s really useful stuff, but if you’re cramming or something, it’s still understandable at 1.25x speed.
Where did the H combined with the NADH came from? is it from the remaining hydrogens of the pyruvate C3H4O3?
If one NADH ends up giving you one H2O, won't you have 10 H2O's on your products side of your cellular respiration equation? Isn't it supposed to be 6?
by the end of 2 years of ap biology course in school.... finally got this shit.... thanks so much!!!!! such an amazing vid!!!!
Am I missing something? When NADH is oxidised and hydrogen loses an electron, how come there are 2 electrons shown in the oxidation equation? shouldn't it be 1electron? Please explain. Its around minute 3 in the video. Many thanks
i just wanted to say that everyting is much easier with your videos, great job
did anybody else find it slightly funny when KHAN/sal describes the inner axle of the ATP synthase 11:47
Isaac Hernandez Woah no need to rip into the guy...
Thank you, but actually it would be also (/more) correct to say that NADH is being reduced. It's not acting as a proton/electron acceptor in this reaction. But oh well
So this is the introductory level and yet this is MCAT level... I guess it's true what they say - MCAT is a mile long and only an inch deep. Good luck, everyone! We can do this!
sir you are graduated in every sub???? you xplained chm absoultely amaazziiinnggg n now bot i can say that ur voice is most audible......
To be 10 years old this video helped me tremendously. For anyone interested look up some atomic force microscopy images of the ATP Synthase. 💚 Science!
THANK-YOU !! but who's the inhibitors of ETC ?
please reply fast
Where do these ADP's come from that they can become ATP's? I don;'t believe you explained that.
very helpful . but am wondering why Khan academy it is not available 4 Sudan ///.
NADH produces-2.5 ATPs and FADH2-1.5 ATPs
I totally agree, that is what we were told in BTEC science.