Microtubules | Cells | MCAT | Khan Academy

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

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

Can be taken OOf. I love the accent

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

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

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.

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

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

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

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

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?

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

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

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

thank you efrat, its really helpful x

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

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.

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

It is very clear 💗 thank you so much.

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