Cellular respiration is a catabolic process which involves the intracellular oxidation of glucose or organic molecules through series of enzymatic reaction producing energy in the form of ATP with the release of CO2 and H2O as byproducts.
This is the summarized video on Electron transport chain
3 stages of cellular respiration:
1. Glycolysis (Glyco=Glucose; lysis= splitting) is the oxidation of glucose (C 6) to 2 pyruvate (3 C) with the formation of ATP and NADH.
3. Electron Transport Chain:
ETC is the step by step transfer of high energy electrons through a series of electron carriers located in multienzyme complexes, finally reducing molecular O2 to form water with the formation of ATP by chemiosmosis.
- Organelle: Mitochondrion
- Site of Electron transport chain: Mitochondrial Inner membrane
- Proton (H+) pumped into the intermembrane space creating proton gradient
- ATP synthesis occurs towards the matrix region (see the above figure)
Background info: At the beginning of electron transport chain we have NADH and FADH2 synthesized during Kerb’s cycle and glycolysis. Approximately only 4 ATP are synthesized directly (2 from glycolysis and 2 from Krebs cycle) from a glucose molecule. The rest ~32-34 ATP are synthesized during Electron transport chain (ETC) by chemiosmosis.