The mitochondrion produce a substance called adenosine triphosphate. It is also known as ATP. It is believed to be our source of energy. ATP's main purpose is to transport chemical energy within cells for metabolism[2]. Metabolism is the sum of the physical and chemical changes that take place in living organisms.
Stem cell harvest. Stem cells used to be harvested from the bone marrow. That has now largely been abandoned in favour of harveting directly from the peripheral blood.
In the laboratory, scientists have cloned stem cells from human skin and egg cells. This is significant because the process could eventually be used to produce organs or other parts that are genetically identical to the patient's own, and therefore, pose no risk of rejection when transplanted.