A harmonic balancer sounds like a crucial part on a spaceship in some pulpy 1950s sci-fi story, or something you need so you can play music with hobos when you're ridin' the rails. However, it's actually an important part on your engine that helps your crankshaft last as long as possible.
U.S. National Library of Medicine (5.00 / 1 vote) Rate this definition: Mitochondria. Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae.
Mitochondria are the membrane-bound structures that produce energy for cells. The mitochondria are thought to be descended from a once free-living cell that set up a symbiotic relationship with a... Mitochondria are the membrane-bound structures that produce energy for cells.