The glycolytic reaction pathway from glucose to pyruvate is comprised of 10 different reactions. The overall reaction catalyzed by pyruvate dehydrogenase is a single reaction that connects glycolysis to the tricarboxylic acid cycle by the synthesis of acetyl-CoA. The TCA cycle reaction pathway rom Acetyl-CoA to oxaloacetate is comprised of 8 different reactions. Considering these 19 total biochemical reactions, how many of them require some type of vitamin-derived cofactor or vitamin-derived substrate?