Mitochondria are the energy source (“powerhouse”) of the body

Energy metabolism is the process most cells use to convert food (carbohydrates, lipids, proteins) and oxygen into energy. The final steps of this process, by which organic molecules are broken down to release energy, take place within mitochondria. Mitochondria are small organelles located in the cytoplasm of eukaryotic cells surrounded by an inner and an outer membrane. Important pathways of mitochondrial metabolism coupled to the production of energy include oxidation of pyruvate by the pyruvate dehydrogenase complex (PDHC), beta oxidation of fatty acids, citric acid cycle (Krebs cycle) and oxidative phosphorylation. Oxidative phosphorylation is the process in which energy-rich molecules with a high electron transfer potential (NADH and FADH₂) are used to reduce molecular oxygen to water by a series of electron carriers. As a result a large amount of free energy is liberated, which is utilized by complex V to generate adenosine triphosphate (ATP) as essential universal cellular energy carrier.

Mitochondria are responsible for creating more than 90% of the energy needed by the body to sustain life and support growth.