Steady states and the Michaelis Menten equation | Biomolecules | MCAT | Khan Academy

Created by Ross Firestone.
Watch the next lesson: www.khanacademy.org/test-prep...
Missed the previous lesson? www.khanacademy.org/test-prep...
MCAT on Khan Academy: Go ahead and practice some passage-based questions!
About Khan Academy: Khan Academy offers practice exercises, instructional videos, and a personalized learning dashboard that empower learners to study at their own pace in and outside of the classroom. We tackle math, science, computer programming, history, art history, economics, and more. Our math missions guide learners from kindergarten to calculus using state-of-the-art, adaptive technology that identifies strengths and learning gaps. We've also partnered with institutions like NASA, The Museum of Modern Art, The California Academy of Sciences, and MIT to offer specialized content.
For free. For everyone. Forever. #YouCanLearnAnything
Subscribe to Khan Academy’s MCAT channel: / @khanacademymcatprep
Subscribe to Khan Academy: kzbin.info_...

[@azuansofian2822]

he keeps on slapping me with these letters and i dont wanna live no more

[@storm7063]

same dude, i am going to live in a box

[@walkerwatters8607]

Need an update buddy, how are you doing two years later?

[@HasanJawhar-dl9rn]

did you pass biochem ? @@walkerwatters8607

[@anau.1122]

you can say I'd KM[S]

[@Lovely-bh3ln]

I love this comment thread ive been laughing at them for 10 minutes now 😭😭😭😭

[@amyheart5567]

ahhh..... 3 weeks of lecture condensed in a clear and organized manner into 7 and a half minutes. Thank you so much.

[@winterbabyXOXO]

Tip: put the settings on 0.75 playback speed, and pause every time he writes a new line, making sure that you understand the logic of how he got there

[@littlesnakeuu413]

dude THANK YOU! I've been reading my notes over and over again and still quite lost in the derivation. You explain it quick & nice, I finally understand it. honestly i don't think it's too fast or anything. i kinda like the pace cause I tend to lose focus if the vid is too slow or long

[@w00tplayaw00t]

I learned so much more from this video than from reading an entire chapter two times. -.-

[@ChimeraGilbert]

But perhaps reading the chapter helped you understand the video!

[@gomamon15]

Exactly the reason i am here. Read the chapter and helped a little but the video tied it together.

[@dorianl.210]

generic comment number 2314423

[@amberants]

THANK YOU!!!! Rewatching my bichem lecture three times, and attending two tutorial classes i thought i was never going to learn this. its so dang simple when you explain it. THANK YOU!

[@arsallansiddiqui9106]

Usually i love your videos Ross, but seems like you rushed this one a little too much ! it was very complex indeed!

[@sasisarath8675]

Complexity is just more layers of information. Chinese is more complex than English. Everything is relative.

[@emkay7233]

OH. MY. GOD. literally what ive been trying to understand in past 7 hours has been summed up in 7 minutes. I LOVE YOU.

[@saarkoene2761]

Very usefull! Taking a course on enzyme dynamics next semester and need to know michealis menten kinetics but never learned it. I feel like this video will really help me!

[@InceptionSolver1]

This is significantly more helpful than listening to my biochem teacher haha

[@dorianl.210]

comment number 232359

[@carlmariepebenito2664]

same here lmao

[@martinstanchev1432]

THIS!!

[@sccm100]

Desired speed Sal: 2x This guy: 0.75x

[@jessicahoff8574]

sebastian cuello painfully accurate

[@knucklescapricorn31]

Thank you so much, this was very helpful. I never really understand Kcat since a lot of sources just focus on defining Vmax and Km. Cheers :)

[@thegigisup7]

THIS WAS AMAZING! AS A CHEM E STUDENT WITH LITTLE TO NO EXPERIENCE IN BIOLOGY, I THANK YOU! :D

[@Dizzifizz]

Perfect video, literally. Well paced and so informative. Breaking concepts down too much can often cause complications hence I love the well paced style of teaching by this educator.

[@amateurphilosopher2307]

This makes so much more sense. Thank you so much!!!

[@apolospetertai6506]

This video helps me to understand some of the concepts that is critical in my studies. Thank you to Ross Firestone to create it. I also thank my lecture Dr. Missa for encouraging me to watch this video. Much appreciation.

[@zekeg9893]

literally none of this makes sense to me.....

[@ukno918]

Review chemical kinetics

[@elizabethvelma266]

😂me too!

[@mohamedwael2026]

great...I was struggling to understand it in my lecture but now I find it easier and more clear ..thanx 👍🏻

[@269Tanya]

OMG, YOU DO NOT KNOW HOW MUCH YOU HAVE JUST HELPED ME! THANK YOU SO MUCH!

[@vodanh7514]

8 min video >> 45 mins in class. Thx, really appreciate ur work

[@maryambaj9901]

Thank you so much !! This was absolutely helpful :)

[@tinieblas6429]

You helped SO much, thank you for the wonderful explanation!!

[@irinikobold1084]

dude we had this class at my uni, and even tho the biochem professor said the exact same things, somehow you made them understandable in comparison to what he said. And English isn't even my mother tong. Thank you very much for this helpful video plz dont ever stop

[@Jonathan-rf5cp]

I like this. My only problem with it is that Km is defined in terms of S. Km is already defined by the rate constants of the individual reactions (k1, k-1, k2). Probably more accurate to say that *when* [S] = Km, Vnaught = Vmax/2. edit: rather than the other way around, let Km = [S]. Semantics but conceptually clearer this way.

[@Davereal8822]

Ain’t no way this video actually that good that it clearly brings together my book, notes, and other vids

[@janakhabouri8271]

This video is good and condensed and DAMN BLESS YALL

[@Hayley1234356789]

Thank you so much! This was so helpful.

[@kw_2707]

Thanks for completely writing all the steps of the equation out. I never understand formulas/equations unless it's actually shown WHY it is the way it is

[@zuhayousuf9197]

Love this video so much. Thank you!!!

[@nourkamaly9496]

This is the first time i've ever found the khan academy videos not helpful, you're going way too fast dude!!

[@jessicahoff8574]

Nour Kamaly same and it sounds awful when you slow it down. Rather have the option to speed up the video. I’m sure it would be a wonderful video if it wasn’t already sped up.

[@HariKrishna-nt6rc]

it is very helpful . u should see manytimes to get it clear..

[@soleegaming3201]

It's seem the result (the understanding of the explanation) is different for different people...

[@sasisarath8675]

To me every khan academy video is slow I totally avoid the whole thing and just code.

[@YZ_KRaZee]

Check once again...you would've probably set it on 2X 😂

[@srishtikhurana4487]

This video saved me from getting a panic attack. Thank you do much for explaining it so well.

[@omarmahmoudofficial]

2:12 - 4:50 wtf happened -.-

[@EduardoMartinez-fk2pv]

Ace Case you need to know a little of kinetics first, the speed of a reaction is v=K*[R]. R being the concentration of the reactant and as a correction factor they add a K

[@ledinah6039]

math

[@blitebeats]

lmao

[@Boo-tw4xd]

Ifkr?!

[@sagestation7831]

You should watch the first video to this series. In addition, the Michaelis Menton equation is used to describe rates. You should know what rates, and kinetics are (usually taught at the end of Chemistry as Chemical Kinetics) to understand what a K value is. You can have a whole 2 hour lecture on what K values are. For this video, just recognizing that it's a constant is sufficient.

[@Healthtips-mv6kn]

My bio chem teacher took 2 hours to explain this! LoL

[@PepsiT98]

Thank you for breaking this down!

[@KiranJagtap5050]

Really useful! Thank you so much!

[@applejackzo]

Visual learners across the globe thank you for this video.

[@sadachalk3150]

Slow down!!!! I usually love your videos but this is way too fast!

[@nabie981]

thank you! It was a bit fast but i loved to stop and rewind! ^^

[@parakhmody1413]

Please answer this question at the earliest, if possible: Are "V" (the one you introduced in the beginning of the video), and "Vzero" (the one you started talking about halfway through the video), the same thing?

[@MichaelH3948]

V = reaction rate V0 = initial reaction rate (reaction rate when time=0)

[@rimse272]

THIS WAS SO HELPFUL THANK YOU THANK YOU THANK YOU

[@mary.b92]

I've never understand it before watching this video, thank you a lot

[@HoangNguyen-js3ot]

Amazing! Thank you very much

[@megha7564]

please answer this: why did we only consider k2 for calculating reaction rate! ie v0 in vo=k2[ES]

[@saileshkrishna8013]

Absolutely brilliant ❤

[@dma67111]

you just simplified an entire 8 pages of derivation thank you

[@user-oy3td7ui6i]

واقعا خیلی خوب توضیح داده شده ممنونم❤

[@JAMScover1]

This is so helpful thanks!

[@subhanazaan3041]

Thank uh soo much, I read lots of notes but cant understand derivation abd concept but now its all are clear just bcz of uh jazak Allah Khair

[@joshb4025]

Fantastic explanation, best I've watched

[@Somenath_Sen]

wow that's really a lot of information in 7 mins. Awesome video.

[@christophergoudarzi9992]

Really helpful videos, thanks so much!

[@alfi991]

You should be clear that KM is an equilibrium constant hence the upper case K and kcat is a rate constant therefore a lower case k, here you don't show that and it's a very important fact when you takes these things further.

[@manwaiwong1774]

Thank you very much!

[@JanelleMontano]

Thank you so much!

[@jessicabehnam3207]

thank you. this helped alot

[@nathanrumpf5660]

Very helpful. Thank you

[@shwetadongre4847]

Short n sweet video ,just perfect

[@Mark-ht1ed]

Beautifully explained.

[@diabolowho]

thanks for the explanation!

[@Yeeeeeehaw]

Thank you very much ! very useful video

[@maryamrahmannia4812]

Great job

[@MrNailbrain]

Very helpfull despite having to pause a lot.

[@marknjama9634]

Thank you so much

[@dimahaddad7664]

Thank you... Thank you.... Thank you ❤❤❤

[@witchkingofa]

Awesome video man, keep it up.

[@maryamrahmannia4812]

Thanks a lot , u saved me

[@duncanjones2272]

Nicely explained/derived

[@wafasaliha1552]

just thank you

[@shadibarghout1313]

I see a lot of people complaining but honestly let's just thank him for doing this for free, the video is more than ok if you know what each term means.

[@artyomstrelnikov8549]

thank you very much))

[@holmspeterson7544]

Excellent explanation.

[@johngrey1074]

The math/derivation is beyond the scope of the MCAT.

[@jhlee9634]

I have a question! Why does steady state assumption only apply to enzymes, not to inorganic catalyst? I understood this that inorganic catalyst has rate-determining step, but enzymes don't. Why do enzymes don't have a slow step? Is it because of the structure of enzymes? It would be really helpful if you could answer me!

[@arieldroger5291]

Usually have to watch videos on 2x speed, not here! Thank you!

[@torvoldsvenson1539]

The old format where the videos were in real time on a black background were so much easier to learn from. These videos that are in fast forward are good for review but way to fast to learn something and there is no time for the detailed explanation that makes it memorable....

[@zia-ur-rahimazadofficial]

very helpfull really

[@livelaughsalang6013]

Me checking to make sure my video was at normal speed 😂. But thank youu, good explanation just had to watch it couple times.

[@bkzwolf]

The one logic gap that I continue to struggle with is how is the FORMATION of ES equal to the LOSS of ES AFTER the elimination of K-2. You no longer have the breakdown of the Product (which does make sense, given the stability of it) but then that's an entire source of ES production that isn't there!!! So you have 2 routes out of ES (formation of P and breakdown of ES to E+S) and 1 route to ES(formation of ES from E+S). Still holding the initial belief that was applied to 2 routes out and 2 routes to. The only way I can sort of make it make sense, but not confidently, is at the beginning of the reaction where K1 and K-1 might hold more weight than K2 but I'm not sure I'm right with that idea.

[@juliazsommer]

I know this comment is old but I think ES stays constant even after elimination of K-2 because there is so much substrate that when ES forms P and the enzyme goes back to being E, it finds another S so quickly that it almost immediately forms another ES

[@AK-di4rv]

Although this video is fast, if you follow him and pause it and rewind at your own pace it is not that bad. The reason you want your Km to be low is when looking at the graph it has a linear form at the bottom which means your substrate is low and the enzyme as great efficiency hence the linear characteristic of the graph. Then as the substrate increases the efficiency of the enzyme goes to zero as shown by the graph going to zero velocity.

[@deathrat]

to anyone out there: WATCH IT AT LEAST TWICE

[@leenasarkar1325]

best one

[@user-qi4df3uz2l]

This guy is way better than my biochemistry professor

[@user-ej1nj5ry6l]

ㅇㅈ 대학 수업들을필요 없음 유튜브에 치면 판때기하나놓고 설명 오지게잘해줌

[@mohsinkashif3674]

you are great

[@parakhmody1413]

Please answer this question at the earliest, if possible: Would it be fair to say that the dissociation of enzyme substrate complex (to product or back to substrate) is a first order reaction, and the formation of the ES complex (from substrate) is a second order reaction?

[@MichaelH3948]

That is correct however, as [S]>>[E] k1 (E+S = ES) can in practise be considered a first order rate reaction as the overall concentration of S changes very little over the course of the reaction (The reaction is only really dependent on the concentration of the enzyme). It's what is known as a "pseudo first order rate constant"

[@jojowa4196]

really good video! :) But what exactly is k_1, k_(-1) and k_2? are they constants for the time it takes to form the new state? (say, it takes 3s to form ES from E and S, so k_1 = 3s?)

[@muntahanoormuskan6431]

These are rate constants. Rate constants are obtained by dividing product concentration to the power of their stoichiometrical coefficient by substrate concentration to the power of their stoichiometrical coefficient. Rate constant has no specific unit, it changes with the reaction. (Correct me if I'm wrong, learned that 5 years ago)

[@alsinbad3772]

k cat is actually just k2, I love it when biologists just name the same variable with diff terms so that the math part can look complicated.

[@njay7246]

Thank you very much for the video but why do you make Km=[s]. Isn't Km a constant?

[@reshmi5333]

This is the second time I am watching this video.in 2014 I was so naive.now I understand everything now.lol I was such a fool

[@maryc5905]

really really helpful!!! tytytytytytyyty

[@sabissu5965]

I think it was very helpful, I don’t understand why people r saying that it was too complex or fast. The subject is not an easy one and you don’t have to know all of the steps for the last formula. And you can still watch it again or slow the video down.

[@jannahalotaibi9728]

Do I need to know how to derive the equation for the MCAT?

[@dylanbinu10352]

Wasn't exactly able to follow the derivation of the formula to the fullest but everything else was extremely helpful. Definitely not for beginners though haha. Read the textbook first, guys! Or watch a simpler video

[@aze90]

Future of education!!, so much better than readling the long boring books where the author is probably paid per page written.

[@gillesbaumann675]

amazing video! Really good explaind?! Thanks a lot !

[@hammadahmad920]

Good to see a brother muslim Helping the students all over the world Allah is great

[@blakryptonite1]

I understand it, but it took me over an hour. I had to rewind, pause, think, and then move forward with the video.

[@user-xn2yv2hi2q]

i love you khan

[@tenzinphuntsok1]

quick question, why the lower the Km value better is the enzyme while the higher Vmax is better ? since Km =Vmax/2, higher Vmax leads to higher Km.. isn't it ?

[@radio146]

Can someone give this person a medal please?

[@americanbee]

I agree!!!

[@gulamgaush72]

me too😍😍

[@danielsaddawi-konefka5951]

What's the difference between Kcat and K2? if Vmax = kcat x [E]t and vmax also = k2 x [E]t, are they the same?

[@venus0.o153]

I have the same question