Chemistry Forum

And why does oxidative phosphorylation make a cell more adicic?

I'm told that during glycolysis pyruvate is reduced by NADH and this turns pyruvate into lactate. NADH loses an electron and becomes NAD+.

This increases the ratio of NAD+/NADH (a redox pair).

Why does increasing the NAD+/NADH ratio make the cell more alkaline?

Glycolysis is the process in which one glucose molecule is broken down into two 3-carbon compounds called pyruvate. Pyruvate is not reduced in glycolysis, instead glucose is reduced to pyruvate. NAD+ is the key electron carrier which reduces glucose by accepting the H+ ions and forms NADH. Since acidity of the cell is controlled by H+ ions, the cell is now slightly more alkaline as H+ ions are carried away by NADH. After glycolysis, pyruvate is only converted into lactate when there is insufficient oxygen present. When there is less oxygen, the body undergoes anaerobic respiration and pyruvate is reduced to lactate and only a small amount of ATP is produced. On the other hand, in case of aerobic respiration pyruvate goes through the Citric cycle where it is further reduced by NAD+ and FAD giving us NADH, FADH₂, CO₂, and GTP. During oxidative phosphorylation, the H+ ions carried by NADH and FADH₂ are released making the cell more acidic. The H+ ions help in setting up the proton potential gradient with the mitochondrial matrix which is then used to produce ATP from ATP synthase. Increasing the NADH/NAD+ ratio makes the cell more alkaline simply because the number of H+ ions are reduced from the cell which are responsible for acidity.