Microtubule



__**Introduction**__ Microtubules are the third principal component of the cytoskeleton. Microtubules' job is to determine the shape of the cells and to determine its movements. Also it is involved with the separation of chromosomes during the process of mitosis. Microbules are composed of tubulin, a single type of globular protein. Microtubules are important for maintaining cell structures. There are many proteins that bind to the micro tubule, in it includes motor proteins such as kinesen and dynei. It is composed of tubulin, a single type of globular protein. Microtubule formation starts with a process called nucleation, this process requires of tubulin. And in that phase an alpha and a beta tubulin molecule join together to become a heterodimer. And they will become a long chain that will become a long series of rings of 25nm. In each ring there is 13 beads. The second phase is called elognation, which happens a bit faster than the first phase.
 * __Structure/ Function__**

Microtubules are like conveyor belts. They move organelles and chromosones attached to proteins. They are also like a skeleton.