Transcript for:
Understanding Glycolysis and Energy Production

all right we're gonna be talking about glycolysis today we're gonna break this process down so it's really easy to understand all the way from eating a doughnut to actually running and using energy we're gonna talk about pyruvate and lactate and how this all fits into the big process of bioenergetics so let's dive into it all right so we just ate a doughnut and we need to make energy out of that so when we eat the doughnut we're gonna digest the doughnut through the stomach and then through the lining of the small intestines and that little bit of doughnut when we go into the molecular level we call that glucose a glucose molecule if it's in the bloodstream we just call that blood sugar or blood glucose and that's where we're gonna start the process of glycolysis now from blood glucose we can go to a couple different places you need to stay in the blood but there's kind of a limited amount of that you could also go to short-term storage which would be in the muscle or the liver as glycogen or to long start term storages fat but when we're talking about glycolysis we're using that blood sugar from carbohydrates and then we're going through the process of glycolysis all right so we're gonna kind of distinguish between aerobic and anaerobic glycolysis although those terms are a little bit misleading so glycolysis happens in the cytoplasm of the cell so it doesn't technically require oxygen but the environment of the cell basically determines the end product of this process so if the cell is in an anaerobic state meaning like you're sprinting then we're gonna generally go through an anaerobic glycolysis all the way through to a lactate molecule at the end so if that cell though is just in like a walking or a jogging or a sleeping State that cell is just going to be taxed to the extent that it would go through that oxidative system and it wouldn't need to produce lactate so let's go ahead and break down the anaerobic first and then we'll come back to the aerobic so anaerobic glycolysis again this is a process where you're at a higher activity level you're expending significant amounts of energy and we're gonna break all the way down to lactate so to start off guys we have that little bit of donut that glucose molecule so remember that glucose is just this molecule so this we can think of it as just like a microscopic piece of doughnut it looks like this under microscope it's six carbons it kind of actually makes a circle shape but we're just going to draw like this it's a six carbon molecule that's a glucose molecule the process of glycolysis guys the name tells you everything you need to know glyco lysis so big picture here the process of glycolysis is cutting or lysine a glucose molecule in half so when we have that glucose molecule and we cut it in half instead of a six carbon we're left with two three carbon molecules and we call those three carbon molecules pyruvate now if we're in an anaerobic state and we want to kind of get the most out of this without having oxygen we're going to go and take that pyruvate and we're actually going to go all the way to lactate with it so the benefit of that is that we're going to turn an NADH into an nad plus and then lactate is our end product this can accumulate in the blood and that's where we think there's about things like the lactate threshold where you know at anytime we have a certain level of lactate in the blood if it starts to accumulate from a lot of the anaerobic glycolysis process happening then we get to a threshold basically where you can't clear lactate now let's go ahead and talk about that clear into lactate that is actually called the claw recycle so as you can see here guys lactate can enter the liver so this is the liver you can actually have the byproducts of that anaerobic glycolysis go through the liver and then turn back into glucose so generally speaking anytime that something is turning back into glucose we call that gluco neo Genesis so that just means making new glucose so the creation of new glucose again just sound that word out gluconeogenesis that's not specific just to lactate amino acids can do that fat's actually go through acetyl co a and then turn back into glucose so that process of gluconeogenesis kind of puts that lactate all the way back to the start and then if you're in anaerobic state you could take it through a aerobic glycolysis again this aerobic glycolysis would be the cellular condition that you have oxygen so if that cell has enough oxygen we're going to go through to pyruvate the exact same so we're still going to have that six carbon glucose we're still gonna cut it directly in half into two pyruvate molecules but again if we have oxygen the next step of that is we're going to go down to the Krebs cycle the krebs cycle requires oxygen and that's why we kind of distinguish this aerobic glycolysis from anaerobic so from that pyruvates the next step is actually to take this oxygen molecule and then have one of those three carbons from the pyruvate jump onto an oxygen and then it becomes co2 that co2 molecule just gets you know basically pushed out of the cell back into the bloodstream and then it goes out and you exhale it through your lungs and that way we're left with just a seat oka way this two carbon molecule and that's what's going to go into the Krebs cycle so whether you're in aerobic or anaerobic glycolysis we're still getting those two net ATP so we're getting energy from this process guys glycolysis actually costs two ATP and then produces four ATP but we get a net of two ATP that's what you actually get out of it again that's one glucose molecule you get two ATP if you think about it per pyruvate you would actually get kind of one ATP per pyruvate but given one glucose molecule you'd get two ATP so glycolysis is an enzymatic process meaning that enzymes push it to go faster the rate-limiting enzyme meaning the most important enzyme for keeping glycolysis going fast is pfk which is the abbreviation for phosphofructokinase all right guys so if you don't have oxygen then anaerobic glycolysis just ends in lactate and that's it but in that oxidative situation you're gonna continue cellular respiration with the Krebs cycle being step 2 and then oxidated phosphorylation being step 3 if you guys want to learn more about that go ahead and check out this next video and if you got anything from this video go ahead and smash the like button it helps other people find this video instead of all the other boring bioenergetics videos that are out there and go ahead and hit subscribe guys because I have a lot of other videos coming out that are gonna be helpful for you