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.
Stem cells come from different places, depending on the type of stem cell you are talking about. In leukemia and lymphoma, stem cells may be transplanted into the person with cancer to help replenish the bone marrow for production of new blood cells.