The flying insects classically utilize high numbers of mitochondria in flight muscles. In addition, mitochondria are organelles within eukaryotic cells that yield adenosine triphosphate in which the foremost energy molecule used by the cell. For this reason, the mitochondrion is sometimes denoted to as the powerhouse of the cell. The mitochondria are originating in all eukaryotes which are all living things that are not bacteria or archaea. It is thought that mitochondria ascended from once free-living bacteria that were combined into cells.
