Split reins are a piece of equipment used for communicating with a horse while it is being ridden. Split reins are actually two separate, individual reins that are used together, with one rein on each side of the horse's neck.
As discussed above, mitochondria are the sites of respiration, and generate chemical energy in the form of ATP by metabolizing sugars, fats, and other chemical fuels with the assistance of molecular oxygen.
Quick Answer. The primary function of the mitochondria is to produce ATP, the molecule that the cell uses for energy when carrying out essential functions. The process by which glucose is converted to ATP in the mitochondria is known as cellular respiration and occurs in mitochondria of both plant and animal cells.