Mitochondria is called the powerhouse of cell. They are so called because they carry out the process of aerobic respiration and generate the energy molecules (ATP or adenosine Triphosphate) for cell operation. Mitochondria oxidize pyruvate (obtained from glucose) and NADH (generated in ctyosol). Pyruvate oxidation takes place through the process known as Krebs cycle or citric acid cycle. A proton gradient is established across the cell membrane during aerobic respiration, which is beneficially employed to generate ATP molecules from ADP. Aerobic respiration is a preferred mechanism as compare to anaerobic respiration. Aerobic respiration can generate up to 38 ATP molecules from glucose. In comparison, the energetic yield of anaerobic respiration is much lower at 2 ATP molecules (per molecule of glucose metabolized).
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