Microtubules | Cells | MCAT | Khan Academy

[@guguwf1991]

I learned more in 13 minutes of your video than in 2 weeks of class, thank you very much!

[@thibauteloy6841]

maybe because you were playing to candy crush instead of listenning the teacher ? ( I am joking)

[@carolinegreen4771]

Microtubule is a much more complex molecule. The building block of this protein is a dimer called tubulin, which is composed of two sub units: α-tubulin and β-tubulin. α-tubulin and β- tubulin form a filamentous chain called “protofilament”. Microtubules are built by arranging 13 such protofilaments around an empty core. This gives rise to a tube-like construction (hence the name microtubule), which is stiffer, longer and wider than actin. Microtubules have a distinct organizing site called the “centrosome”. Microtubule polymerization begins at this organelle. The end where faster polymerization occurs is called the plus terminus. The end where slower polymerization takes place is called the minus end. Microtubules grow from the centrosome towards the membrane, by anchoring their minus end to the organelle. Once microtubules reach the membrane they detach from the centrosome and create a highly dynamic network. The formation of this network is assisted by a group of proteins with microtubule binding domains called Microtubule Associated Proteins (MAP). -Creative BioMart

[@um1569]

That's exactly the kind of information I was looking for in this video, nonetheless it was a fantastic video, gave me more info than my professors did lol

[@nilanjanadani5629]

Hey! May I know at what standard are you studying these Microtubules and stuffs? And from which country are you studying?😁

[@hafsahjan4107]

great...thankuu soo much...this helped me a lot.....stay blessed

[@virupannamedikinal]

Thanks

[@Santa1936]

Can be taken OOf. I love the accent

[@hannahjohnson5755]

I feel like Harley Quinn is teaching me cellular A&P. It’s appropriate

[@shreenidhhi8633]

oof

[@uwuboogaloo857]

UOFF

[@hainan3717]

omg mee too

[@BehzadAmiri-pm2pp]

Bacaaaauuuse

[@briansalkas349]

Error at 3:13, centrosomes do not duplicate during mitosis, they duplicate during the S phase.

[@harshinidavuluri878]

You 're right!

[@lukehoising6401]

it duplicates in G2

[@sakshamsingss]

DNA duplicate in s phase not centrosome

[@heebz6805]

@@lukehoising6401 S phase of interphase along with DNA not during G2, microtubules are made during G2

[@manuelblank8072]

Correct me if I'm wrong, but aren't interpolar microtubules the ones that do not attache to kinetochores, but go from one MTOC directly to the other?

[@MrFreakj]

Interpolar microtubules are connected to the interpolar microtubules of the other MTOC. Kinetochor microtubulues bind the kinetochors. So I learned it that way, too.

[@farihaakhter3946]

This vedio is very helpful for all of us who want to know more about microtubules very descriptively or elaborately...

[@ntethelelocilo3728]

ngithande nje izwi lakho ntokazi yomngisi....i learnt a lot from this video, thanks!

[@pragyasharma8238]

understood all the basic concepts .. cleared my head with all the doubts by watching your video..thank u !!

[@kiranakhtar7788]

Time saving explanation... thank you so much

[@AvParreira]

A great presentation that takes a very dry textbook concept and makes is simple to understand and grasp.

[@redshark618]

I dont know if her accent is NYC or NJ, but I love it

[@sowmiyasubramani1323]

Clear accent , and explaining ,, choose this kind of people to explain the session

[@rawda2167]

Thanks it helps me a lot !!!!

[@johnvandenberg8883]

Great work Efrat! New York accent? I love it how you say "beezlebaddies"

[@rehanahamid4328]

Centrosome is absent in plants....how spindle fibers are formed in them

[@erikak6450]

I learned about microtubules AND Canadian accents today. Thank you!

[@betb48]

Wish i had a teacher like you at highschool...very well explained....

[@ayoadeodebode4405]

Great illustration. I must point out that the centromere and kinetochore lead the motion, not the arm of the chromatids as illustrated.

[@guynouri]

Fast and furious

[@Eyosias-x1g]

I love the way you say because

[@doanviettrung]

This teacher makes everything so clear. Anyone knows her channel, please? I want to subscribe.

[@ايهاببيانو]

You are great.

[@شمسالدين-ط9ظ]

now i understand the paclitaxol and the other taxols mechanism of action thank you so much

[@angelavolkov1126]

Can also grow by branching, not just linearly

[@TadFishy]

There is a mistake in your video. Interpolar microtubules are antiparallel microtubules that originate from opposite poles, and overlap at the midzone of mitotic spindles. They don't attach to kinetochores. The ones you showed are kinetochore microtubules. Would be good to make it clear that there 3 types of microtubules taking part during mitosis and they all have different functions.

[@al850416]

Thanks

[@Max-vi9is]

Anyone here to understand orchestrated objective reduction?

[@Tante90Emma]

One of the best khanvideo I have ever seen.

[@kevinbennett5226]

You sound like you grew up in New York but now live in Canada

[@Salvation0fMind]

Kevin Bennett My thought exactly

[@guynouri]

Excellent clear clearest yet

[@LeaBrigitteMagret]

Thank you so much!

[@jaquesfrancais3030]

9:19 I think there is something incorrect, in the 9+2 arrangement of the basal body the central microtubules are NOT paired as the other ones (1 complete and 1 incomplete microtubule, who attach each other). Indeed, the central "pair" is more like TWO SEPERATE and both complete microtubules, just connected by a bridge and not direcly attaching, as your drawing suggests. Pls correct me if I'm wrong.

[@guyseavey6634]

Very well presented. It is very helpful when so many details are presented in a way that is easy to retain. Thank you for a great video lesson.

[@yiiyatschan1395]

Thank you for this video.

[@rangineechoudhury3755]

Well explained.

[@russelmiller7311]

Both the mitotic spindle and the interphase cytoskeleton are formed from rapidly tuning-over microtubule populations with half lives of less than a few minutes, which grow from and shrink towards the microtubule organizing centres.

[@valfredodematteis-poet]

you are great at teaching, thank you

[@pinkfrosting0]

Love the jersey accent. Great video :)

[@OperationCyanide]

it's new york

[@tkal123]

This is a very helpful video of an otherwise very confusing subject. Thanks

[@nikiene5764]

There is a mistake in your video. The 'interpolar' microtubules in the video are actually kinetochore microtubules. The interpolar microtubules extend from opposite poles and meet each other somewhere around the center where they overlap and associate with motor proteins.

[@colife5486]

wow- one of the best Khan Academy videos I've watched. thank you so much!

[@foadazizpur7442]

URGENCY QUESTION: in the fungi, how chromosoms move in their nucleuses? does the strips of duke transformed from cytoplasm to nucleus?

[@annikas2225]

This is so helpful for my AP Bio test!!! Thank you!!!

[@ahsanahmed1393]

Hi is your degree finished...??

[@leahgrausam5368]

This is a phenomenal video! Well done! Thank you so much!1

[@ChildishDicaprio]

All I got from this video was “OOOF” lol cool accent

[@TheSharkSoul]

I'm so grateful for this!

[@himalaydebsourav]

An excellent class.

[@johntindell9591]

great work

[@khamikos1]

perfect.thanks

[@zannatul23]

thank you efrat, its really helpful x

[@oraclebjj]

Reminded me of school again. Lots of labelling of parts less actual explaining of how stuff actually works. Are those tubules in the neuron as she calls them "tracks" transporting electrical signals? Or something else.

[@lovelytangcalagan9264]

kimura kano No electrical signals aren't "transported" and the tracks that she showed are within the cell. The actual electrical signals that neurons transmit are passed in its plasma membrane through a complex process involving ion channels.

[@Leengoi]

Thanks a lot..i pass the test because of your video 🤧🤧 Got 15/16 🤗

[@leefrancis-q5v]

very good video if u are student who got exam 2 days after

[@enacausmembrane]

we actually say "2 days from now". The Word "After", makes it seem like you are studying after the exam has already ended.

[@misssweethearted]

this was actually pretty good

[@ahmadaamir7684]

Extremely helpful

[@comfortkaimbo3]

this was a good job well done

[@wardhammoud]

Much appreciated

[@FatimahWaleed]

It is very clear 💗 thank you so much.

[@Petrov3434]

Kudos to Lynn Margulis

[@normadicn5700]

Lovely accent. 🤩

[@slehar]

Wow!!!

[@krisanthonysilveira8244]

Just a small correction doesnt the microtubule arise from the pericentriolar material rather then then centriole ??

[@ingaa.]

Thank you so much, this video helped me a lot for a presentation!

[@ayaabdi9141]

thank you..

[@Twoplusfouris7]

Great job!

[@matthewlee4834]

I liked her accent, but it took a while for me to understand when she was saying "anchoring" at 4:09 xD

[@sudiptasahaniloy976]

thank u so much buddy..... :)

[@tanishagavali5171]

This was so good.

[@godhelpme8977]

Hi

[@angelavolkov1126]

Neat :)

[@zannatul23]

thank you, you are a lifesaver

[@shikhakashyap5591]

I just loved this video😍😍😭😭

[@godhelpme8977]

Hi

[@shizzassimplesciencesss5590]

Coool, I never liked khan's but this lady overwhelm me, keep it up miss unknown u r doing great

[@peculiarezindu1043]

Tnx for the teaching but signals did not go back they go forward from d dendrite to the axon terminal and then d axon terminal takes received signal to another neuron and so on continuously,,,,tnx again ma'am

[@MikeyIV]

How do most cells transport vesicles? Just in the cytosol, no railroads? Also what holds the organelles of a cell (nucleus ER, etc) in place? Is that microtubules?

[@yashikaraghuwanshi7634]

Intermediate filaments hold the cell together I think, and the railroads you talk about, are microfilaments.

[@hamidizouina4787]

plzzz what aplication do you use ???

[@chrisjernigan1912]

Shouldn't it be cawled the 9 +1 arrangement?

[@lemongreen4828]

Isnt the 2x Centriole at right angle known as a Centrosome?

[@ThePassportPapi]

bring back khan!

[@aidabach]

How did the inner pull microtubual become shorter when they pulled the chromosome apart? Did they take off the middle part or the end parts?

[@al850416]

They take off the + ends as she mentioned in the beginning where the plus ends could be either addition or taking off tubulins. There is a motor protein at the kinetochore that does the cutting.

[@Shimulnath96]

Let me clear,, During synthesis phase(a phase of interphases) do the whole centrosome become double or only centriole become double?

[@kashish291_0]

Whole centrosome

[@Shimulnath96]

@@kashish291_0 thanks

[@godhelpme8977]

Cilia and flagella 9 + 2 Centriole 9 + 0

[@BrandonSLockey]

why are there no more detailed videos on this :(

[@Cl0udn1n3]

Strings + sticks = strix. Microtubule mem

[@user-xb7vt7pk7l]

That's a lot of protein names to remember

[@niloufarm.n6330]

What's this app u use for drawing?

[@Andrew-kh7rz]

Is astonishing how much information is wrong on this internet

[@tomasmieger6826]

Amazing stuff - Thx.

[@meeha7604]

How do u spell dionene correct way and what would happen of some consumes more then that is required by the body and where is it devised from plants or animal what is the structure of it compound element ? What would happen if tubular over grow do that me brain mass grows

[@swerasharma5218]

slay video

[@TheFr3styler]

I thought Centrosome wasn't an organelle? 2:12

[@AvocaSingleTrack]

Brooklyn ? Queens ?? ...haha

[@ellastewart8122]

kind of vague.i still dint get the main functios of microtubules

[@Greenthumb-420]

does this come up on the grade 12 course or biology 30? im in process of needed to redo mine dont wanna waste my time learning it, if i dont need to

[@benashley2955]

if microtubules are dynamic then how is their structure studied

[@jamesfilosa6277]

Great!! Thank you!! One correction: kinetOchore* (it's spelt with O, not I) :S

[@bingingawaylife8405]

Why is it 9+2? It should be 9+1

[@madisonmarano2171]

you must be from Jersey with that accent !!!

[@fizzyoddball]

I’m only 14 😭😭😭😭

[@sajidaiqbal3688]

isnt it kinetOchore

[@FishoeShoe_da_great]

5:06 is this inside a cell or a nucleus?

[@afroditi5760]

This is a cell..

[@sushritbisht7863]

This girl’s from Brooklyn!?