Mitochondria are known as power house of the cell because they generate ATP, the energy
currency of the cell. Terminal oxidation takes place through oxidative phosphorylation. This produces ATP. Even the reduced coenzymes produced in cytosol through glycolysis, transfer their reducing power to mitochondria for ATP synthesis. ATP synthesised inside mitochondria provides energy for all cellular activities including over coming tendencey for entropy. Hence, known as power house of the cell.