So we discussed lactate dehydrogenase and we said that lactate dehydrogenase is an enzyme that is basically involved in glucose metabolism. And more specifically, what it does is it transforms pyruvate into lactic acid, it reduces pyruvate into lactic acid and that at the same time oxidizes NADH into NAD plus. And what that allows us to do is it allows us to regenerate NAD plus. And so that means we can basically restart another cycle of glycolysis. So we see that lactate dehydrogenase catalyzes the reduction of pyruvate into lactic acid at the same time and oxidizes NADH into NAD plus. Now, if we examine the quadrantary structure of lactate dehydrogenase LDH, we're going to see that it consists of four individual polypeptide chains.