Electron Transport Chain

[soumyasayujya]

i' have mastered cellular respiration.....just have to memorize those protein names.......tat won be tough...since i love them now...they will get into my head pretty fast!!!....thanks a lot sir!!!......

[entertainme151]

Oh my god, you make bio interesting again.

[DryBonesandSilver]

i can officially get a 5 on the AP bio exam. thank you for saving my life!

[RegionalMisrea2010]

wow,i have a final tomorrow and i haven't studied my slides at all,just watching your video's!! they're so awesome! I fee like the Einstein of biology!!!!!

[cameron1737]

Technically, NADH+ is 'worth' about 2.5 ATP, and FADH 1.5, but I wouldn't imagine 1 ATP being that big of a deal. Besides, I rather like the thought of an extra ATP. Great work!

[mamba1066]

thx for saving my life

[NisaMaisara]

great tutor./

[fcoroa]

Not only do you explain the basic concept of the ETC, you also help undestand a process that everyone refused to explain. I didn't understand how NADH and FADH2 could magically turn themselves into ATP just by letting it's electrons go through a transport chain! Thank you, kind sir!

[CreatingMagic]

I have a question about 3:36 you say that 2e- + H+ and 1/2O2 make one comple H2O but I seem to be missing one H+. Am I looking at it in an incorrect manner? Still a great video though, really really helpful!

[iRudby]

Honestly what the point of showing up in class if we go to youtube videos to relearn everything in one hour :| I fucking hate useless teachers that can't teach shit or too lazy to =__=

[ozkaa]

you got vision salman!

[izzahgul]

although every student is sitting seperately behind the computer screen, Your lectures "feel" like an interactive classroom :)

[namu0727]

Sorry but I'm totally in love with you. :)

[knullesen]

Its 2,5ATP from NADH and 1,5 from FADH2 now :) nice video though

[partypopper2011]

this video is awesome!

i now have a good grasp on the ETC

THANK YOU!!!!

[superfairyberry]

brilliant video!

[AllAmericanEmily]

15:33... you're welcome. :)

[x3TeamAlicex3]

THANKS SOOOOOO MUCH!!

[MrAcademedical]

Krebabs cycle,

1.Big night drinkin beers and watching KhanAcedemy videos

2.Eat Krebabs

3.Gets to sleep 3 in morning

4.Sleep in, aces uni exam

5.repeat

[lissau3]

You helped my knowledge just over the edge after reading a whole lot of textbooks which tries to explain it in words. Explanation with words are good if you have a visual understanding of what is going on, and with your video I now have that understanding. All my knowledge on the subject came together with this video. Thank you khanacademy.

[daves106]

I struggled a bit with this explanation initially but I watched another animated video by vanitavance and it helped me visualize some of the sequences a bit better. I can now understand these sequences more now. So there's a tip if anyone is having the same trouble.

[daves106]

Ok then time to watch again!! brilliant teacher but I'm struggling here!! keeping at it though!



[mrmarquessa]

i am a science dummy but have been plowing through a biology textbook lately. Amazing stuff. this is a great video. all the videos by this guy are excellent. it's wonderful to at last understand this stuff. thanks a mil!

[fitnesspoint2006]

darkdanne - you deserve a cookie because only a virgin would pick up such an oversight when the overall concept by Khan was explained in such an elegant and beautiful manner

[lost4468yt]

@fitnesspoint2006 He has a wife and kids.

[a262982850]

You help not only somebody who use Eng as mother language

You help International students!!!!

[AHMADISNOTJEWISH]

I could kiss you after watching this

[merly77]

I'm convinced you know everything.

[hockeymo]

atp synthase is so fascinating

[darkdanne]

Dude you forgot a "2" in front of the proton in the reduction reaction

[kimboklinger]

This is so helpful. All of your videos are. Thankyou

[Ace220X]

I'm in BioChem I, so I need a deeper level than this, but my professor couldn't even get the basics across in a clear manner. Thanks a lot.

[Flipinredpiklez]

dude u are sooooo much better tan my bitchy bio teacher

[aliciaxxily]

I have a test this week and I've been confused for 2 weeks now. THANK YOU SO MUCH FOR THIS !

[midgetman9942]

Holy shit...incredibly interesting.



[bettyjane007]

So the gist of this is that electrons from NADH and FAHD2 go through an series of reactions called the ETC, then energy is used to pump H+ goes into the inter membrane space, and then those H+ go back through the ATP synthase, and help make ATPs. Electrons at the end of ETC are recieved by the oxygen and makes water.

[MrsPoker]

For those interested, the turning part has been proven some time ago. Nobel price was given if I remember correctly. They connected a long actin filament to the spinning part, and made pictures, seeing it spinning around!

[starlette098]

"im not gna go into the details" NOOO ! Go into the details :'( i neeeeed it. Screwery beyond belief!

[theSamosa1]

Is it true that the NADH from glycolysis only produce 2 ATP each, and the NADH produced in the mitochondria produce 3 ATP each?????

[AllDayEveryDay2471]

you explain this better than my bio teacher!!!!!

[LOseattle]

You're amazing. This vid taught me more about the ETC than I learned from my own professor this quarter. THANK YOU!!!!!

[TOproFORthis]

cool!

[TheKmanOfSmash]

Wonderful videos, Mr. Khan. You are doing a grand service for mankind. :)

If I may ask, you said that the energy derived from NADH oxidation (and I assume a similar process occurs for FADH) is used to pump H+ protons from the matrix into the outer membrane of the mitochondria. I believe I understand that much. So where exactly are the H+ protons coming from? Because at first, I thought that they came from the byproducts of NADH oxidation, but then I realized that they all got turned into H2O.

[Staciiiz]

I can now take my AP Bio test with confidence! :D

[Maria00angel]

At 01:54 you are wrong:

1 NADH2 -- 2.5 ATP's

1 FADH2 --- 1.5 ATP's

it makes a big difference when you are calculating the overall ATP's

[NBAfan1993]

@Maria00angel true was going to make the same comment

[NBAfan1993]

@Maria00angel but how would you calculate it?

[TheTdwpforever]

Why do we want hydrogen protons in the outer membrane? Why do we want it more acidic?

[vagrantaim]

wow!!! Intro to cellular respiration video; CHECK. Glycolysis video; CHECK. Krebs cycle video; Check; And now transport chain Video; BIG CHECK! one weeks worth of confusion solved in 1 hour. :)

[wasianwigger]

More detail in your vids please! if you could do some awesome more advanced vids like these it would be amazing

[colacastell]

99% of Teachers are Jerks, 1% produce vids on youtube!

[Froschritter]

Thx for the explanation, it helps a lot... though I have to tell you two "mistakes" I noticed:

The first thing is at about 3:30 you need another proton to form hydrogen with the oxigen and the two electrons (of course you know that but you might want to add a litlle text box ;))

The second thin at 13:21 You say it pushes the two ATPs together, I think you mean ADP and Pi together to form an ATP.

If I missed something let me know and thanks a lot for your work again.

[Rikaiden]

quoting my biology textbook, it says " the hydrogens from reduced FAD stay in the matrix but can combine with oxygen to form water" and later it adds that theoretically " the total yield of ATP molecules, per molecule of glucose respired, should be 30."

why does every book give me different information, which is correct? khan or my textbook? help would be appreciated.

[arpinz]

I understand better this lesson in english. Im french.

[BecauseRiceIsAmazing]

THANK YOU! This makes sooooo much sense! :D

[inthewayofallah1]

thanks

[vaust5]

at 17:02, shouldn't there be only 2 ATPs created from glycolysis?

[hockeymo]

@vaust5 it says from glycolosis AND krebs

[vaust5]

@hockeymo

Oh, my bad. I didn't see that

[TheKmanOfSmash]

@vaust5 If you look more closely at 17:02 again, you may see that Mr. Khan actually wrote that 4 ATPs are produced from Glycolysis AND the Kerbs Cycle. In Glycolosis, 2 NET ATPs are generated (2 ATPs are used up the "investment phase" of glycolysis and 4 ATPs are generated during the "payoff phase." 4-2=2 ATPs) and 2 ATPs are generated from the Krebs Cycle. 2 ATPs from glycolysis + 2 ATPs from Krebs Cycle=4 ATPs.

You had the right idea. You just did not see him write the "Kerbs Cycle."

[NBAfan1993]

@TheKmanOfSmash are you considering the conversion of pyruvate to acetyl CoA a step from the Kreb's cycle?

[TheKmanOfSmash]

@NBAfan1993 What do you mean? I think Mr. Khan said that pyruvate oxidation was an intermediary step before the Krebs cycle could begin, so no, I guess. But I'm not sure what that has to do with my question. I'm sorry if I'm not understanding your intentions clearly.

[Fotbalfan64]

Khan academy is better than any amount of lecture ive ever had. it makes learning this so much more simple!

[PoGoNugen]

Why is it only 1 H+ for the 1/2 reaction of H2O? Shouldn't it be 2H+???

[gelario20]

THANK YOUUUUU! My teacher shoud've shown us this video in class instead of lecturing us. It would've been so much easier for both of us :D.

[TheGreatSaboner]

I guess I'm just among the minority when I say that after the three cellular respiration videos I'm still as confused as before....I sort of get how ATP is produced in the ETC but not really... fml. :( Nice job though, most people get it..

[RoCHeL23]

i thought i was going to be hopeless for my exam tomorrow, but i think your videos are going to save me! thank you soo so much! you're the best biology teacher i've ever had (:

[blhoff42]

all i have to say is thank yo,. i may not due well on the test i'm going to take right now, but since i just discovered all of your videos.. i know i'll crush all of my bio tests from now on. you're awesome!! :)

[R0ck911]

wow, speechless at how u can make me understand this when my teacher can't! thank you!!!!!!!!! you're a life saver : )

[mathilda411]

I'm in grade 11 and have found these videos more helpful then any of my bio IB classes thank you so much

[pareody]

He make cramming for my AP Biology test at 1:30 am possible. Thank You!!

[wakwas]

@pareody im cramming for my biology test too lol 

[angelkiru1]

u r a nice teacher...thanks it helped me a lot!!

[greenday00648]

Mr. Khan, I know you probably won't read this but I just wanted to thank you so much for how much you've helped me understand and learn. You are wayy better than any teacher I've ever had. I learn more here than at school. Thank you so much.

[bloom250737]

Cellular and Molecular Biology made simple--- THANK YOU!

[heyitsyasmineb]

OMG THANK YOU IM PASSING MY TEST THANKS TO YOU

[usmansharifmicky]

This makes me wish I was born later in time so that Sal could've completed all his videos...and this whole idea would be fully developed..and yeah.

[gustavo85304]

Wish you were my professor. Great job simplifying complex material!

[jejemon005aque]

thank you

from this video i learn more .. :DD

[Herucross]

FUCK JESUS.

YOU'RE OUR REAL SAVIOR

[megaacdcfan1]

You are the greatest!!! My textbook can go to hell

[CurtisThorpe]

Thank you! These vids are great!

[killaboi3sk]

Can you upload a video about how to do yield problems for cellular respiration? Like calculate the amount of ATPS produced?

[J4CKC4RD3N]

that was really helpful ! thanks ;)

[jaclynhagan]

dude, now i won't fail my bio exam. SAHHHHWEEEETTTT

[rawrl2121]

Can you be my teacher? :3

[mcklewie27]

thank you! YOU ARE SO WONDERFUL! thanks to you i understand a.p biology!

[brooklynA33]

You have monumentally saved my butt! If all professors were as detailed and brilliant as you are, there would be a dramatic drop in the amount of all-nighters being pulled ! :)

[windragon379]

Sal, you're epic, a hero! My teacher explained this 4 times, and I felt really dumb because not once could I get it. You? You actually explained it slowly and simplified it so I could see the big picture, and I could finally understand the details (in glycolysis, for example, my instructor didn't tell us what pyruvate was, but, thanks to you, I got it). You're THE best! :D Thanks a million!

[helen3kr]

Lovely and wonderful illustrations! thank you! but..well ATP production can differ every time depending on what receives the 2NADH s from the glycolysis. Since NADH can't directly enter the matrix via diffusion, 2 NADHs from the glycolysis transfer their electrons at the inner mitochondrial membrane.. when electrons enter the membrane, either free FADH2 or free NADH free floating in the mitochondrial matrix picks them up. so, it will be more like, 32-34 ATP + (x)ATP from 2NADH s

[Riptide4656]

Please be my college teacher. You are very clear cut!!

[MrSneekz18]

Only 32 ATP is produced in total, not 34 as indicated in the video

[MasterMindxD7]

@MrSneekz18 Actually, if you look at the video. He says that we have 10 NADH and 2 FADH from previous stages. Each NADH produces 3 ATPs. So, in total we will have 30 ATPs from 10 NADH and each FADH produces 2 ATPs, so in total we will have 4 ATPs from 2 FADH. Adding these two numbers of ATPs we will get 34 ATPs.

[MrSneekz18]

@MasterMindxD7 But that is incorrect. 2 of the NADH from glycolosis gets turned into FADH2 as it enters the matrix, resulting in 8 NADH and 4 FADH2, 8*3=24,4*2=8 and 8 plus 24 is 32.

[hanmann1988]

@MrSneekz18 Your right theres only released 32 ATP per glucose molecule. But it's a nice demonstration of whats happening. Thanks

[LaLablink]

thanks so muchhhh! seriously... :DDD

[PowerTheQwerty]

i have seen just how many people are grateful for your work and how they have written paragraphs thanking you, but seriously you are amazing! i have been revising the ETC for around 4 days, this video explained it in 17 minutes.. thankyou so much!"!!!

[mscullen2]

wow! this is so easy to understand!! god i was having such a hard time studying!

[fennel18]

that was amazing! thank you so much for clearing things up. Ive been trying to understand this topic from my notes but have had no luck for the last 4 hrs. this made everything clear in 17 minutes! thank you and please keep doing what you do!!

[bscottallstar]

This is my first comment on any of your videos - I am pre-med and making up for a lot of lost time studying the sciences (I was a communication major). These videos have become an indispensable part of my study arsenal and this last one has blown me away. I am constantly amazed at the way you make the big-picture so visible and cut through the trivia (at least temporarily as it is inescapable after all). Your lessons have prepped me for formal study to no end and I thank you endlessly!

[Lancegriffiths]

5 people aren't cramming for a physiology mid-term ^^^^^^^^^

[Jimmyfrominwood]

so much information your are amazing!

[mrwright0630]

Isn't this Electron Transport Chain called Oxidative Phosphorylation?

[mlpiper11]

If only my biology teacher could have explained it like this! thank you!

[classicwiseguy]

:( i love your videos but wish it was more detailed, maybe like a 30 min video...i gotta know all of the enzymes, and the parts of the atp synthase and all that

[muzic347]

mind blown, in a good way :D

[xoxomariamxoxo97]

could u explain this process in more detail? my book explains it a bit more condensed but i dont understand it. but overall, this video is great!

[ThePolishMafioza]

what note software do u use? 

[ytimg62]

@ThePolishMafioza Smoothdraw 3

[kingdavidtaidawei]

is H+ acidic or alkali? cuz protons are alkali in chemistry

[No1Brawler]

@kingdavidtaidawei Acidic

[rajeshs12345]

For those of you that are a little bit confused... The H2O reduction equation is supposed to have 2H+ (Sal forgot the 2).

BUT overall a great video :) a great help to me for my APBIO test tomorrow :)

[totallykeet]

@rajeshs12345 yeah i saw that Hplus and was thinking how did he get water from 1 H plus and 2 electrons

[DudeyLad]

Very, very good. Couldn't resist clapping in real life after watching this and the Kreb's cycle video.

[Rafen45]

isn't it so that 4H atoms are added to 2 NAD s and we get 2 NADH2 s ?? Atleast that's what's written n my book.

[ddelsouz]

you are AMAZING.

[dier69]

I want to marry you.

[DrPopips]

I love you, you made my life so much easier!

[nergal27]

Sal, I am sure you get to many comments of appreciation to keep up with, but thank you so very much. I just wanted to say that the reason I have been able to do well in class now, which will lead to my goal of being a doctor, is really thanks to you awesome videos. You make complex ideas simple, without simplifying them! So hopefully one day when I become a doctor, or anyone else you helped makes a break through that helps the world, you were a big part of that positive inovation trasport chain!

[youngarmenian]

super helpful...thanks guys! :)

[holumyde1]

Damn! He makes biology sound like a love story. bet he is a product of bollywood!

[naveen48850]

thats a good video to make students understand the concepts....

[Korac92]

5 people must be professors who couldnt explain it better hahaha

[catwesage]

My AP Bio textbook started crying then ran away after seeing this wunderful video =]

[Constans69able]

Did any one else notice the mistake?

He is still a genius though and an incredible person who i believe saved our butts from failing

[happybro1]

so the electrons from the NADH when its oxidized is used to transfer the hydrogen to the outer part of membrane?

[KissMyHerpes1]

@happybro1 Yes, oxidation of NADH to NAD+ releases electrons and energy. This released energy allows the first protein complex in the ETC to undergo a conformational change (or change in shape) that permits the complex to accept the electrons produced by the oxidation of NADH to NAD+. The change in the protein complexes shape by energy released from the oxidation of NADH also permits the complex to shuttle or pump the H+ ions that are produced by oxidation of NADH.

[happybro1]

@KissMyHerpes1 ah thank you! the changing shape was what my teacher said as well, thanks!

[frigidfingers]

It is amazing to understand the process, a "factory" if you will, from one molecule of glucose to 38 ATP. Cellular respiration is amazing!

[xxchristinee16]

Mind = blown.

[BecauseILoveeMusic]

Wow I understand now, Thanks! Thought I never would :P

[Regnier77]

I fap to this video. You are amazing sir.

[idiotic1021]

this is not sufficient for my med school biochem..we need to know about all the protein complexes...FML

[sun7ss]

Btw. will you be able to make a video on "synthesis of fatty acids"? That would be lovely, because it's what I have in the university, and find it extremely difficult to understand.

[daniellelovin]

We watched a video on this and the krebs cycle in class.... they have got NOTHING on you. Thank you for the videos- they are SUPER helpful. And you aren't all mono-tone and boring, you make it tolerable.

[frryyyjk]

A thing of beauty

[dont138]

mmmmm NAD FAD

[mattvocalPHHS]

You, sir, are a BOSS.

[supersuper18]

AMAAAAAAAAAZING , BLESS U

[Felix0890]

I wish diarrhea upon this chapter. -.-

[fatin161]

if only my lecturers are able to speak and explain as good as you.

awesome vid. thanks!

[fifivolivassve]

hey, do you have some chemistry jokes?? - Na. :D

[adamal93]

@fifivolivassve sodium and chlorine was kicking it on the dancefloor. then chlorine ended up together with hydrogen -albert einstein

[BBP081]

Okay I do not fully understand cellular respiration, but I suddenly became a lot more interested.

[alacowboy0]

i am taking online courses having to read all the books by myself and this video was very useful in helping me understand. cheers

[bee8brith]

waaaaaahhh... thank you very much! i thought i'll never understand biology!

[NbulianJohn]

this is excellent teaching. my own suggestion is after you listen to this video lecture, just watch an ETC animation to get the absolute idea and everything will be crystal clear to you.

here is 2 animes i can recommend you:

****youtube.com/watch?v=xbJ0nb­zt5Kw&feature=related****

****youtube.com/watch?v=xbJ0nb­zt5Kw&feature=related****

[afonsords]

fascinating

[DanceMinhjaU]

I wanted to add something to this. The 38 ATP is for prokaryotes because the NADH from glycolysis that occur in the cytoplasm don't lose energy because they don't have mitochondrial membrane. However, for eukaryotes, the yield is 36 ATPs since the 2NADH have to cross the mitochondrial membrane via a transporter protein. Hope this helps! Overall, great video and good luck with studying about electron transport chain :)

[Andoryuuspenis]

Thank you,my test is tomorrow and my teacher is cuban...I'm cuban to btw.

[bustbloodcancer]

i love you man...thanks!

[RpAthlete]

So let me see if I understood this. The whole point of the ETC is to pump H+ into the Mitochondria outermembrane which causes an electrical gradient and then H+ wants to go back into the negative Matrix through ATP Sythase which creates 3 ATP per NADH?

[MsDraca]

HELP!

tomorrow I'm going to write a test about

" - glycolysis - respiratory / citric acid cycle - final oxidation "

does that mean that you can call the citric acid cycle respiratory cycle?

and what the hell is the final oxidation?

btw: thank you, mr. khan! Ohne diese Videos hätte ich echt Probleme.. DANKE!

[KeiRuud]

As the axle of the ATP synthase turns around, a phosphate group bonds with the ADP forming ATP. Where does the matrix or the ATP synthase get the ADPs necessary for this process to take place? Is there like a pool of ADPs, FADs and NAD+s in the matrix of the mitochondria?

[migmar]

Professor Khan: A Gift from God to future Biologists!

[g0deaterzx]

After watching this, i have no idea what the hell im doing in school when i learn more infront of my com watching these videos

[rinangel0]

@g0deaterzx amen!

[whatever189e]

I love you Mr. Khan :) :) <3

[Tseuas]

I love you. :') <3

[ullasrajchellappan1]

Mr.Khan i dont know who you are or where you are...but if i happen to meet you one day , i want to treat you a big dinner..just to say thank you..You are a wonderful person who go the extra mile to help people..this topic was so difficult for me,,even after going through tons of materials i could not come to an exact point of understanding..but your video changed all that..by the way why the teachers cant teach at least half this good..!!

[TheOverkill1]

I think I'm in love with you.

[MayTheApple]

Which people are so fucking annoyed that they dislike a video biology lesson(which is by the way the best one I've ever had) ?????

[Zangetsusk1]

It took 17 mins and 16 seconds to change my life

[PuffleWuffles]

Shit, I was in the silent study space and accidentally clapped like crazy after watching this...

...You sir, are my saviour.

[PetStuBa]

@whitefangpwin, sorry, can't help you with the NAD-2H, because I have not seen this yet in my course

it's NAD+ , so 1 positive H-ion and two electrons to reduce the NAD+ to NADH

[WhitefangPwnin]

I was wondering if NADH is the same as NAD-2H? In my textbook NAD-2H will give two positive H-ion and 2 electrons. In your oxidation, NADH will give one positive H-ion and two electrons. How come?

[PetStuBa]

@kristinelkeller

Some eukaryotes (like liver and knidney cells) have transportproteins which bring electrons inside the membrane, there they form matrix NADH and generate again 3 ATPs.

(I'm not sure, I'm not an expert)

[marshmellowcloud]

i might as well watch this in biology instead of listening to my teachers.......

[carendale]

i am taking microbiology online and this is SO helping me picture it all better! thank you thank you!

[kristinelkeller]

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.

[JollyBiscuit]

you pretty much saved my life

[hyp3rn0s]

omg thx so much man! I now understand! My teacher seriously cannot teach...

[4seasons4lifetime]

hey! i think you made one small mistake

the H+ protons that are pumped by the protein complexes are pumped into the intermembrane of the mitochondria not the outermembrane :)

otherwise this awesome!!!

[madej1858]

what's the function of the electron transport system and its ability to produce ATP?