An autosome is a chromosome in a eukaryotic cell that is not a sex chromosome. Unlike prokaryotic cells, eukaryotic cells have many chromosomes in which they package their DNA. This allows eukaryotes to store much more genetic information. Basically it just isn't their job.
Centrioles play a role in organizing microtubules that serve as the cell's skeletal system. They help determine the locations of the nucleus and other organelles within the cell.
