An organelle that synthesizes adenosine triphosphate (ATP).

The mitochondrion is a type of organelle that has the outer membrane and comb-like inner membrane. Mitochondria are rich in enzymes that work out the citric acid cycle, the electron transport system, and the oxidative phosphorylation system which conjugates the former two. These enzymes oxidize various substrates under the aerobic condition in a mitochondrion, to produce ATP using the energy produced by the oxidation. There are round, rod, or filamentous mitochondria and their size and the number in one cell vary with the species and the cell. Mitochondria have their own genes that are different from the ones of the nucleus.


[Related Terms]
Biochemical energy, Energy source, ATP (Adenosine triphosphate)