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Mitochondria is one of the organelles that are found in living cells and it is the one responsible for the production of ATP, which is the source of energy that is usable by the cells. Mitochondria is designed in such a way that, it will be able to carry out its functions efficiently. Mitochondrial has two membranes, one at the outside and the other one at the inside. While the outer membrane is smooth, the inner one is highly folded and it formed a structure called cristae. The folding of the inner membrane serves to increase the surface area inside the mitochondria.