Microtubule
Microtubules are one of the cellular structures that make up the cytoskeleton of eukaryotic cells. The microtubule is a structure in which the dimer of tubulin protein is a cylindrical shape with a diameter of 25 nanometers. In the microtubule, place the side that is easy to attach tubulin to the + side and the side that is easily disassembled to -. The speed is determined by the concentration of free tubulin, and at high concentrations, it becomes easy to attach anywhere, and at low concentrations, it is easy to dissociate. Microtubules provide cell motility. Typically, the flagella and ciliate are microtubules and are cell organs responsible for the movement of cells. In addition, microtubules are responsible for intracellular transport, transporting cell organelles such as mitochondria and vesicles, and plant cell wall synthesis.