Krebs / citric acid cycle | Cellular respiration | Biology | Khan Academy
HTML-код
- Опубликовано: 10 дек 2009
- Courses on Khan Academy are always 100% free. Start practicing-and saving your progress-now: www.khanacademy.org/science/b...
Overview of the Krebs or Citric Acid Cycle
Watch the next lesson: www.khanacademy.org/science/b...
Missed the previous lesson? www.khanacademy.org/science/b...
Biology on Khan Academy: Life is beautiful! From atoms to cells, from genes to proteins, from populations to ecosystems, biology is the study of the fascinating and intricate systems that make life possible. Dive in to learn more about the many branches of biology and why they are exciting and important. Covers topics seen in a high school or first-year college biology course.
About Khan Academy: Khan Academy is a nonprofit with a mission to provide a free, world-class education for anyone, anywhere. We believe learners of all ages should have unlimited access to free educational content they can master at their own pace. We use intelligent software, deep data analytics and intuitive user interfaces to help students and teachers around the world. Our resources cover preschool through early college education, including math, biology, chemistry, physics, economics, finance, history, grammar and more. We offer free personalized SAT test prep in partnership with the test developer, the College Board. Khan Academy has been translated into dozens of languages, and 100 million people use our platform worldwide every year. For more information, visit www.khanacademy.org, join us on Facebook or follow us on Twitter at @khanacademy. And remember, you can learn anything.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy's Biology channel: / channel
Subscribe to Khan Academy: ruclips.net/user/subscription_...
Students around the world should just pay their tuition fees to this guy.
His site gets millions of dollars from the Gates Foundation already.
James Carmody For good reason
My gf says this a good comment haha
and no one gives a fck about what ur gf thinks
True
good luck on your tests homies
ty G
Thanks a lot
thanks, brother.
Thanks 🥶
Thanks my man
This guys a genius, i couldn't understand this in 2 weeks of Bio class and he just made it so easy in 17 minutes... Thanks man!
pablo nunez why did you send me this i want Mathematics.
@@armaansamirizvi3354 or he was just confused, like me, a straight A (female) student. My bio teacher is the worst teacher I've ever had, he yells at us and drills us in front of the whole class and all of our quizzes are test grades. If that person had a bad teacher its not entirely their fault for being confused.
@@lilykatr0354 same
oh l understand it within 2 classes!
thisbich isn’tspontanious this jacksfilms fan is Tryna flex
I know some of those words.
Why do you get so many likes?
+Masterpiece Kingswood cuz he uses different colours 😊😊😊
he is talking about Irun Mon
+bader alyousef ohhhhhhhh 🙈
This full-on made me laugh! Glad I’m not alone, it’s not sinking in yet 🙃
They don't teach you this on the streets.
shocker
well they won't ask you about this in the streets
phoebe?
yes, watch film on bed is more comfortable
Go up to a beautiful young woman (or man or whatever as the case may be) and ask her to come for a coffee while you explain the latest on the Krebs cycle!
Maybe we'll put a happy little ADP right over here. Remember, this is your world, you can respirate any way you like.
No one comments back ??...well I'm just gonna a leave a simple Bob Ross is love Bob Ross is life here
bless ur soul young lad
i see you're a man of culture
Let's just take that glucose there, wash the pyruvate in enzyme, and beat the devil out of it!
hahahaha
2:13 = My face tying to follow along to my professor in class
that's quite funny.
Spencer Lindgren LOL you just made my day
ohmygod
I do not regret the time investment it took me to get this joke. It was a solid L-O-L out of 5
haha prime example of a distraction
I. LOVE. YOU. Really. These are THE BEST teaching videos ever. I'm in grad school & killing myself over trying to read textbook & follow powerpoint based lectures. OMG. Your channel is a lifesaver! I'm telling all of my classmates about it!!!!!! I would seriously have your child.
+April Camillo Lmao best comment ever. But I definitely agree, these videos are unbelievably helpful.
ur learning this in grad school or just reviewing it cause if ur just learning than i definitely shouldn't be learning this :(
"I would seriously have your child"--real Freak! lmao!
Ypogo Ogi I am having to relearn! I am too old for it!
I totally agree!! I've been reading my PowerPoint repeatedly and nothing was clicking. Watched this once and BOOM! I get it now.
It's amazing how 11 years later this is still one of the best videos available about the krebs cycle!! Thank you!! Be sure that many brazilians students have been helped in these 17 minutes!!
still does!! 🧚🏻♂️
@@sarangave HERE 2024
It took my professor two hours to explain what you just explained in five minutes. Thank You
I wasn't talking about the entire video. Just the part I needed.
lmao
17mins*
I think they just take a long time to explain it just to get it stuck in your head, but that doesn't work on me tho
Watched this video in high school for biology and now I’m back years later watching it again for college bio 😂
Do you want to tell me you forgot it already? Hope that won't happen to me!😄😄
What degree you're pursuing currently?
:))) good luck
@@eriasaine4911 Trust me you're going to forget it too 😬 Unless you revise it everyday of course
@@eriasaine4911 i forget it like every other month lol
He's better than any of my teachers.
CHAOS80120 Far better than anyone
The guy who is narrating must be a fucking genius!! He knows so much on so many diverse topics: bio, chem, physics, calculus... What degree(s) does this guy have?! What is his actual career? He must be some elite doctor or professor or something right?!
Richard Ortiz if u want hear his voice skip to 2:00
+Amin Rosli What are you on about? He's talking the whole video... Plus, your reply was completely unrelated to Richard's comment...
+Richard Ortiz His videos are relatively shallow. They only cover the trivialities, namely in his biology and chemistry videos. Additionally, some of the organic chem videos and biology videos are done by other narrators, people who are more specialized in their field. That doesn't mean he is unaware of the minutiae of each field, it just doesn't seem that way from his videos.
this is true. Personally, this guy's videos help me on an introductory level to the topic rather than an actual learning and processing video. Still helps out sooo much though
Richard Ortiz I mean to be frank this stuff is just basic curriculum you could have done in high school but just simplified for us because he is a teacher
This is why I love Khan Academy, these videos have helped me since I was learning geometry in middle school. Now taking my first Bio class as a freshman in college and I can always depend on these videos to clear up my confusion.
A palpable sense of relief comes over me when I recognize your voice in the Khan videos. “It’s the guy that can actually explain it in a coherent manner”.
omg. this makes sense. I came home from my college class and I was so mind fucked, I couldn't gain anything. thank you so much!
I have a question, when do you study all of this in the USA? Only in college or also at school?
Miru Bauer I'm taking it in college. Its an intro to biology but if you want you can take Ap biology in high school. If you do take Ap bio in high school it won't count as a class when you apply to med school, so you'll still need to take it again.
michael meza thanks! I was studying this for the IB
👍
michael meza college? I study this shit at high school
For someone who learns kinetically and visually, your videos really help. Understood this in 17 mins whereas I was KILLING myself trying to learn it before hand. Thank you so much
I wish I would've seen this a month ago when it really mattered
May God bless you and all your future generations to come, this video is saving my life in Biology.
Agreed
I love you Khan Academy! Dont ever start charging people for your wonderful service. You help so many students.
FYI the NADH produces 2.5 ATP and the FADH2's produce 1.5 ATP each. except for the NADH's produced from glycolysis which can produce either 2.5 or 1.5 depending on the shuttle used to get into the Mitochondria. which means a total of 30-32 ATP per glucose molecule.
It has been a long debate since long.. regarding this .So nothing is much specific .
thank you, i was about to comment it as well
Is this saying that the very action of picking up the electrons alone generates ATP?
little miss know it all
It’s ridiculous how many times I’ve had to re-learn this. I always forget, and will never use this ANYWHERE in my career, so idk why it keeps getting jammed down my throat! 🦔
crying because I have to memorize all the enzymes and names of the intermediates for the krebs cycle for my college biochem class :(((((((((
Well you're done with them, now it's my turn :'(
well i have to do the same and im only 16 😭
I gotta know the structures too and be able to drawing the electrons moving around.
Don't cry, dry your eyes. Here comes your mother with those two little guys.
I have a bio midterm and a few bio tests in less than a week and I barley understand anything in bio from the beginning.. I really need help.. ):
I have used Khan's videos for Algebra, Chemistry, Statistics and Biology. Now I am back using his videos for Microbiology and he always explains everything so that even someone like me can actually understand the material. I love him and I will probably be back for another subject down the road.
NADH and FADH2 are both coenzymes that shuttle electrons. NAD+ picks up 2e- and is reduced to NADH. FAD becomes FADH2 because it also picks up 2e- and 2H+ ions. ADP (adenosine diphospate) picks up a phosphate group during substrate-level phosphorylation, where ADP enters into an enzyme along with a substrate and the enzyme transfers a phosphate group to ADP, thus changing it into ATP (adenosine triphosphate). The prefixes in ADP and ATP tell how many phosphate groups they have; DIphosphate (2), TRIphosphate (3). I hope that helped some of you, I'm no teacher by any means but i hope this clarifies everything, and I also hope my spelling is correct.
Some FAD gets REDUCED to FADH2 not oxidized 8:30
Good observation
Phenomenal. All these years taking biology, I wish I seen this video before med school. It makes everything so much easier.
Thanks to this video I was finally able to understand how Krebs cycle works!!!
For those wondering about the exact number of ATP produced, it varies from 36-38. Remember the two NADH produced in glycolysis? Because they cannot enter the mitochondria, they send their electrons through to either NAD+ or FAD+. Because FADH2 makes 2 ATP each, and NADH makes 3 ATP each, the ATP production goes from 4-6, which are added to the 32 already made.
it’s accepted as 34-36 now 😔
5:15 where Kreb's cycle info starts
As a Papua New Guinean student, this video helped me a lot in my studies khan academy is one of the best and the simplest website for learning.
i was trying to figure this out for 2 hours until i watched this and understood it right away. Khan academy is a blessing from God
The best explanation of the Krebs cycle I've seen so far. Thank you for making it much clearer for us!
so great that you actually mention the whole point of these reactions. when i was in medical school, i was just memorizing steps and not knowing the purpose of the reaction. wish you were my teacher back then! thanks!
I have a test on this tomorrow and because of my remote learning, I've spent 3 days learning about it over 2 weeks. This video alone probably just boosted my grade 10%
Anyone learning this today has NO IDEA how good they have it with YT. Imagine learning this in the 1990s in a lecture hall of 400+, sitting 60 feet away from a chalk board, from a TA that learned English 6 months ago, ONCE, without rewind or replay, having to scribble notes to maybe memorize it for an exam in 3 months.
I'm not going to say that I couldnt learn this with out Sal, but Khan academy is a invaluable resource to solidify the information. Thanks for being awesome Sal!
My last two brain cells are screaming
he's the finest teacher on the planet!
omg i am so grateful people like you do these kinds of things, i have been struggling for days trying to understand this for HOURS from my textbook and powerpoint but you made it so clear and easy to understand in less than 18 mins wow thank you bless you
These are the best explanations that any one studying could never wish to live without am so glad to be part of this team
That moment when not a single word was understood..
iGo0gIe if u don't understand his explanation, you won't understand any other. Sal Khan, the best teacher in the world.
Chetan Shenoy disagree. Everyone learns different.
I LOVE YOU ! You give the 'why" rather than meaningless symbols and you make biochem fascinating, interesting and memorable
Barely. It's yr 12 level and is little more than a vocabulary list.
U r a genius, I have some accident and I need to stay at home for a period of time. And while i was worrying about catching up with my studies, I found this channel and the videos help me in understanding the things I can't understand in textbook. U saved me, seriously
Awwww finally😢😢 i couldn't explain how grateful I am for this video. Thank you so so so much Khan Academy. It helped me a lot. Thanking you wholeheartedly.
best video about glycolysis and krebs cycle out there
Thank you so much for your videos! Because of you, I actually understand concepts that seemed so daunting and confusing.
Thanks so much ! This video explained it better in 17 minutes than my Biochem professor did in 1 hour ! Much appreciated !
Okay so you're telling me that my body can make its own citric acid? So lifetime supply of OJ then??
citric acid is not vitamin c
@@sibby6186 joke
1.25 speed is easier
Martin Sun try 2
Pressure CHALLENGE ACEPTED
Martin Sun I thought the videos were purposely slowed down? You mean 1.5 isn't the default speed?
+nygeek64 Obviously not? :P
Lol it was sarcasm :D dexistence19
this video is 8 yrs old but it is one of the BEST VIDEOS ive ever encountered that helped me understand cellular respiration
wow! this an amazing detailed yet simple explanation. really appreciate how you compare to text book and tie everything together to make sense.
THANK YOU SO MUCH KHAN ACADEMY! I learned the Citric Acid Cycle because of this video.
Wait till you have to learn what all the intermediates actually look like!
Man this is awesome! Nice work!
Ima start hearing this guy omw to any bio class just to have it fresh in my head then revise notes oh the options are endless to study now
Just amazing, Ive been trying to learn this for days then your 17 min video was all it took. Keep it up.
I passed chemistry in high school because of this channel!
i have a test on this tomorrow yayyy
Good luck 👍
you're hot
ayyyy 10 months in the future I have a test tomorrow too Yayyyy
yooo i have it tomorrow too. eksetit
I can't thank you enough! I've been studying this all day and it just didn't make sense, but now it does. I've got my final Biology exam tomorrow (I'm first a year Biology student), and this has saved me. Thank you, once again. Great video.
What I loved about this video is the handwriting and drawing.. it is much clearer than any others on RUclips
Great Video ! Your Voice is so Soothing ! haha not to be creepy or anything lol
Acetyl-CoA is NOT a two carbon compound, however, the acyl *group* attached to the thiol group on coenzyme A is.
i have watched this same video like 10 separate times during my degree and it is hands down the best video to watch to get a quicker refresher on Kreb cycle
I had to donate... I know $10 isn't a tremendous amount but man you have been my virtual tutor for math and chemistry so many times I've lost count please keep up the good work.
Please everyone, if you can donate; then please donate. RUclips education is a Godsend.
Thank you. So much. Currently taking AP Biology right now and hanging on a string.. So in the Citric Acid Cycle, how does NAD+ become NADH, FAD to FADH, and ADP to ATP?
8:30 FAD+ gets reduced into FADH2. Just a note.
Loud is Loud wrong. FAD is reduced into FADH2
This guy should make a new school for everyone. If he did, it'd be the best school ever ngl.
Thank you so much for making each and every complicated topic an easy one . Lots of respect and appreciation to you
Tks for the video, such easy learning, just for curiosity in my case
"easy learning"???
I need a brain transplant!
RPM11111
LOL. No, what you need is more ATP!
Bozeman Science really explains this topic well...
This is exactly what I needed to prepare for my exam next week. Thank you for the detail explanation!
You've saved my life multiple times, and for that I thank you.
Taking a Biology test with nothing but this video guiding me, wish me luck ✌✌
How’d it go?
Hey, just noticed and I was a bit confused, I might be misunderstanding the way you said it but yeah.
You said that FAD gets OXIDISED to FADH, wouldn't it be known as reduction since it's gaining an electron?
he meant reduced
Yeah I was assuming so, just wanted to let him know in case others got confused.
i have a grade 12U biology exam tomorrow and i was stuck on the krebs cycle + electron transport chain the whole semester.. thank you for breaking it down way better than my teacher!!
I love how you explain all of this in a language I understand... If only all prof's could explain in this way.
2:20 my face when I study bio
+Antony Cai That was hilarious!
Hahaha
Lol
NADH makes 2.5 ATP and FADH2 makes 1.5 ATP
NADH produces 3 atp and FADH2 produces 2
+Yasmeen Yasmeena like he says, this is the case in a theoretical perfect cell. However, even after billions of years of evolution, cells are not perfect and energy is lost to entropy. It isn't exact, but 2.5 ATP per NADH and 1.5 ATP per FADH2 is good shorthand.
NADH produces 2.5 atp and FADH2 produces 1.5 atp to account for 32 total ATP, he just rounds up.
Devan Halton Incorrect. They produce 3 and 2, respectively in a perfect cell, as he mentions. In reality you get a lower return for a variety reasons, including proton (H+) leak from the mitochondrial matrix. You're just stating the assumed average.
Alan Blakely it's ussually NADH produces 3 ATP and FADH2 produces 2 ATP molecules don't puzzle your mind
I'm more amazed by your ability to write so neatly !
I dont know what i would do without these videos ! Im definately going to pass my tests with this info! Makes it so much easier to understand thank you!
LilBaby it’s definitely not a spelling test I hope?
its so hard to remember every step in kreps cycle and every enzyme catalyzing it😥😥
One way to memorize the steps in the Krebs cycle is by using this mnemonic: Officer (oxaloacetate), Can (Citrate) I (Isocitrate) Keep (a-ketoglutarate) Selling (Succinyl-CoA) Sex (Succinate) For (Fumarate) Money (Malate). And every enzyme that catalyze these steps have correlating names to the steps. Hope this helps!
wow ty easier now👌👌you are an excellent teacher👍👍
wow thanks
You are a life savior
Wow! Useful AND mildly offensive!
Thank you very much!
This is what the goverment won't tell you.
i am inlove with your voice and every word that goes out of your mouth
We are currently on cellular respiration and KREBS can kick rocks! Lecture exam is today and this has helped very much!
Tbh... I’ve never heard anyone talk about this stuff in their life 😂
Marry me??? I have Khan Academy to thank for getting me through biology
I love how he pulls up the wikipedia image and deciphers the complications of it all. THANK YOU.
Thank you VERY much! Our teacher just threw a detailed picture up via the projector and rambled on about it without any visual simplifications. What you've just highlighted is all we need to learn. Thanks again!
I LOVE YOU
According to my professor's notes 36 ATP's are created all together from the entire cycle... Not 38? Which is right?
some text books and ppl teach 36 honestly just depends on who is teaching you but in a perfect chemical reaction the most possible is 38 but 36 is more common I think
It is largely dependent on the cell type and it's efficiency. For example, cardiac muscle cells will produce more ATP than other cell types, because you're heart always has to beat...but, if you want a general average for all cell types...it's ~ 32. If you're taking a general biology exam, and they ask you how many ATP's are produced, you're going to want to say 36 though. This is because that's how many would be produced at a theoretical 100% efficiency. I hope this helps!
Striated muscle cells create 38 ATP. Most cells, however, create 36 ATP :)
it depends on the shuttle using to transport reducing equivalents into the mitochondria to be reoxidized in the respiratory chain. There are two shuttles, the malate-aspartate shuttle, which if used gives 38 ATP, and the glycerol-3-phosphate shuttle, which gives 36 ATP.
Instead of ATP being produced in the cycle my lectures say GDP becomes GTP
You literally saved my life with this video. I have an exam in 2 days and was so confused! It all makes sense now!
I'm a international graduated trying my best to past USMLE 1. Best explanation I found. I have to remember 8 years ago of 1st semester of med school and I really got frustrasted with boring and so detail diagrams on internet. Thanks :D
cristaayyyy lmao
GLI-COL-AH-CYS OK I GOT THIS...
This is the Krebs cycle, love.
love it already...
Kara Skeleton holy crap that's actually the sweetest thing to say
This guy is actually amazing don’t know what I’d do without him
WOW! I have been so so so confused on this for so long. This video makes it PERFECTLY CLEAR! My university needs to fire my professor and hire this guy. Thank you so much.
I didnt think you could make glucose from fats
+Grant Harmon He gets a break this time. I'm sure he just misspoke and meant beta oxidation of fatty acid chains. Haha
+Grant Harmon That's true because fats are esters made up of triglyceride esters, 3 fatty acid and a glycerol.
+Grant Harmon its called gluconeogenesis and it happens in the liver
+Grant Harmon They both have C H and O molecules. I read that you can.
if i say glycolysis occurs in the cytosol instead of cytoplasm.. would tht still be correct?
Yes because cytosol is basically the aqueous part of the cytoplasm
this is the best answer
Syazlina Aasim Cytosol is the cytoplasm
cytosol is actually the liquid thing in the cytoplasm
Cytosol is in the cytoplasm. You are being more specific, which makes it a better answer.
This was great. Explaining the big picture before delving into the details is the best approach to teaching, and I find that many textbooks do not use that.
A heartfelt thank you to Khan Academy for creating such an amazing video on the Krebs/Citric Acid Cycle in Cellular Respiration! Your video is like a friendly guide through the sometimes tricky world of biology, making learning a joy.