Electron Clinical Chain

Every organism, both plant and animal, require food. The food (carbohydrate, fats and proteins) is then broken down to simpler form to release energy; this energy is utilized in their growth and activities. This is called oxidation of food. The process involves many oxidation-reduction reactions (redox reactions) to produce high energy ATP (Adenosine tri phosphate) molecules. This chain reaction is termed as electron transport chain.

Electron transport chain:

The whole reaction take place in mitochondria.

step 1.- dehydrogenase enzyme activates 2 H and their electron from the substrate (food).

Step 2- H atoms and their electrons ate transferred to H-acceptor NAD reducing it to NADH2.

Step 3- H atoms and their electrons then passes to FAD reducing it to FADH2

Step 4- FADH2 passes H atoms and the electrons to a coenzyme Q10 and gets oxidized.

Step 5- Q10 releases H atoms to cytoplasm and gets oxidized. The electrons are now passed on to a series of cytochromes. Cytochromes get reduced and oxidized alternatively.

Step 6- Finally electrons are accepted by O2. Oxygen then unites with 2H atoms (or 2 protons, released in cytoplasm earlier) to form water. The energy released during the process form 3 ATP molecules.

ATP formation:

A simultaneous process called oxidative phosphorylation take place in which energy released in electron transport chain, is used up to form ATP molecules.

ATP produced (in mitochondria) is used in different functions in a cell