<Dd> 3.11 Inner boundary membrane </Dd> <Dd> 3.12 Cristal membrane </Dd> <P> 4 Mitochondrial DNA 5 Matrix granule 6 Ribosome 7 ATP synthase </P> <P> The mitochondrion (plural mitochondria) is a double membrane - bound organelle found in all eukaryotic organisms . Some cells in some multicellular organisms may however lack them (for example, mature mammalian red blood cells). A number of unicellular organisms, such as microsporidia, parabasalids, and diplomonads, have also reduced or transformed their mitochondria into other structures . To date, only one eukaryote, Monocercomonoides, is known to have completely lost its mitochondria . The word mitochondrion comes from the Greek μίτος, mitos, "thread", and χονδρίον, chondrion, "granule" or "grain - like". Mitochondria generate most of the cell's supply of adenosine triphosphate (ATP), used as a source of chemical energy . </P>

The mitochondrion is host to which portion of cellular respiration (2 points)