Aerobic respiration takes place in mitochondria. Glycolysis/EMP pathway is the initial step which takes place in the cytoplasm. The pyruvate formed as a result of glycolysis is converted to acetyl-CoA which enters the mitochondria. Here the acetyl Co-A is taken into the Kreb's cycle. Acetyl-Co-A is completely oxidised to produce carbon-dioxide and water with the release of energy. High energy electrons generated enters the Electron Transport Chain.