Centrioles are tiny cylindrical tubes found in animal cells, and their job is to help organize the structure of microtubules during cell division. Centrioles are located near the cell’s nucleus and are arranged in such a way that they form a “9+3” pattern.
During the first phase of cell division in animal cells, centrioles replicate to form copies of themselves. According to Molecular Expressions, cell biology researchers are not yet sure how the duplication takes place. Before cell division starts, the centrioles live together in a pair of two groupings of microtubules. As cell division progresses, the original grouping disintegrates into two individual groupings that move to opposing poles of the cells.
The microtubules organize themselves into spindle-shaped structures that span the entire cell. The spindle-shaped fibers help in the alignment process of chromosomes as cell division progresses into the later stages. Although centrioles play a critical role in animal cell division, plant cells are capable of reproducing without them.
Centrioles in cells that have cilia or flagella are called basal bodies. However, in these cells, the centriole groupings are located closer to the cell’s surface rather than near the nucleus. In some organisms, basal bodies don’t have a permanent location, and they are functionally transformed into “normal” centrioles prior to cell division.