Online Resources on Cellular Respiration Overview Living organisms catabolize organic molecules within their cells and use the energy released to manufacture ATP by phosphorylating ADP . Both of these processes involve oxidation of foodstuffs, yet only the latter requires oxygen. In metabolic pathways, coenzymes play a role.
Coenzymes are chemicals synthesized by organisms from dietary vitamins .
Recall that the reduced form is the energetically valuable one, whereas the oxidized form is the energy poor one. It is designated FADH 2 when it is in the reduced form. It may also carry a succinyl group. During glycolysis , the potential energy of a primary foodstuff, glucose , is released during a series of chemical reactions which occur in the cytoplasm . No oxygen is used during glycolysis.