Mitochondria definition
The mitochondrion (plural mitochondria) is a double membrane-bound organelle found in most eukaryotic cells. The word mitochondrion comes from the Greek Î¼Î¯ÏÎ¿Ï, mitos, i.e. thread, and ÏÎ¿Î½Î´ÏÎ¯Î¿Î½, chondrion, i.e. granule or grain-like.Mitochondria range from 0.5 to 1.0 Î¼m in diameter.A considerable variation can be seen in the structure and size of this organelle. Unless specifically stained, they are not visible.he word mitochondrion comes from the Greek Î¼Î¯ÏÎ¿Ï, mitos, i.e. thread, and ÏÎ¿Î½Î´ÏÎ¯Î¿Î½, chondrion, i.e. granule or grain-like. Mitochondria range from 0.5 to 1.0 Î¼m in diameter. A considerable variation can be seen in the structure and size of this organelle.