A centrosome, the connecting point of a centriole, an organelle, is the portion of a cell where microtubules are manufactured. Its structure, since it acts as a nexus for cell activity, facilitates cell division.
In animal cells, as well as those of certain algae and fungi, the centrosome is located close to the nucleus, and consists of a pair of centrioles arranged perpenidcularly to each other (in this case, they are known as diplosomes).
During the prophase of mitosis, the centrosomes migrate to opposite poles of the cell. Between them is formed the spindle, a bundle of microtubules that will function later as the foundation for cell division. Interestingly, the pair of centrioles that make up each controsome is not apparently necessary for the creation of the spindle. When the centrioles are destroyed, for example by a laser, the spindle nonetheless forms and cell division procedes normally.