Enzymes are the substances which helps in the broken down of large food molecules into small molecules. It is because our body is not able to absorb large food molecules, these large molecules are broken down into small molecules with the help of enzymes. Carbohydrate is broken down into glucose by amylase and protein is broken down into amino acids by protease. Enzyme is non-living in nature and used as a catalyst in order to speed up the chemical reaction.
In each glycolytic pathway, glyceraldehyde 3-phosphate dehydrogenase produces 1 molecules of NADH as a result of reduction of NAD+.
Pyruvate dehydrogenase converts pyruvate to Acetyl CoA producing 1 molecule of NADH per pyruvate oxidized.
In Kreb's cycle, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, and malate dehydrogenase reactions produce 1 molecule of NADH each. Furthermore, succinate dehydrogenase reaction produces a single molecule of FADH2 per FAD reduced.
Since, we began with 2 molecules of glyceraldehyde 3-phosphate, we multiply the above figures by 2 and get a total of 10 NADH and 2 FADH2.
