mitochondrion

views updated

mitochondrion (pl. mitochondria) A structure within the cytoplasm of eukaryotic cells that carries out aerobic respiration: it is the site of the Krebs cycle and electron transport chain, and therefore the cell's energy production. Mitochondria vary greatly in shape, size, and number but are typically oval or sausage-shaped and bounded by two membranes, the inner one being folded into finger-like projections (cristae); they contain their own DNA (see mitochondrial DNA). They are most numerous in cells with a high level of metabolic activity.

More From encyclopedia.com