What is a centriole? What does it do? Which cells (plants or animals) have them?

Centriole is an organelle of the cell which is formed from a protein called tubulin. The main function of Centriole is to perform cell division in animals and produce spindle fibers which separate chromosomes from each other in the process of mitosis. Centriole is present in animal cell near the control center called nucleus, while absent in plant cell.