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Learn the toughest concepts covered in Biochemistry with step-by-step video tutorials and practice problems by world-class tutors

Review 2: Biosignaling, Glycolysis, Gluconeogenesis, & PP-Pathway




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the fate of Pirou is then determined by what type of conditions are cell is performing, like Hollis is under and also what type of cell we have. If we have anaerobic conditions in our cells as humans, we are going to generate lack tape. If we have anaerobic or hypoxic, meaning not a lot of oxygen conditions. And we're yeast, for example, we're actually gonna make ethanol and carbon dioxide. And this is actually the basis for making things like beer very important process in human history. Fermentation of alcohol. It's actually one of the reasons that some people, some anthropologists, believe humans organized into societies. But that's a whole other story. And lastly, if we have aerobic conditions are Peruvian is going to be turned into a C Delco. And that's what we're going to talk about in the next unit when we get into aerobic cellular respiration. For now, let's talk about fermentation, So alcohol fermentation. Let's talk about that first because it's a subject near and dear to my heart. As someone who has brewed beer in the past very fun, super awesome process that relies on organisms to actually carry out these reactions. Super cool all right. So basically, what we have on top is the short version of Blake Allah assists, right. We start out with our six carbon glucose. We make our three carbon piru of it. And in the process, we're going to generate a net of two ATP and Thio and a D. H. And the whole point of fermentation is that in the absence of oxygen, we can't use that in a th two fuel oxidative possible relation. So we have to do something with it because we need mawr n 80 plus to keep Glen Collis is going. There's not just infinite and 80 plus in the cell. And so the cell has to take that in a th do something with it to make more n 80 plus to regenerate an 80 plus, it needs to oxidize and a d H. And so fermentation is the way ourselves accomplished that. And again, the whole point is to sustain, like Allah assists in the absence of oxygen. And it's worth noting that actually some cells on Lee do fermentation are red blood cells. For example, Onley carry out like Hollis is so they rely on fermentation in order to keep like Hollis is going now. Of course, our red blood cells don't do alcohol fermentation. Otherwise, we'd all get drunk when we go for a run. And obviously that doesn't happen. We do lactic acid fermentation, which we're gonna get to in a second. So in alcohol fermentation, here's our pirou bait. What's gonna happen is we are going to D car box. A late, our pyro of it. And remember, our carbon numbering here is three or for to five and one or six. And we're going Thio de car box late. This group right here. Right, So the c 02 that's leaving, That's, uh, that carbon is either carbon three or carbon four from Glucose. What we're left with is a molecule called, uh, a seat, Aldo Hide and a seed. Alba. Hide is going Thio contain carbon two or five and carbon one or six. And this molecule is currently, um, somewhat oxidized. Great. We have a carbon Neil there. It's going to get reduced by n a. D h. And remember, Of course we have. We have to any th and we have two of these molecules for everyone. Glucose we put in and it's going to get reduced to ethanol. Oops, I wrote ethanol, ethanol, and just to be crystal clear, that's carbon two or five. And that's carbon one or six. So that's alcohol fermentation. And the whole point is to recycle and 80 plus that we can continue like Hollis ISS. Now, let's take a look at lactic acid fermentation. Or what was the Cory cycle named after the guys who discovered it? And here, Piru of it is actually going to be direct, directly reduced by an A D H to form lack tape and n 80 plus. So again, we have our one guy, Kalle ASUs. I'm sorry. One glucose go through Glen Collis ist make a net to a t p to any th and we're gonna have to Piru Bates numbering is same as above. And here any D h is going to directly reduce this molecule Thio lack tape. This molecule, this is black tape and that's going to regenerate n a d plus you can see we're reducing this carbon Neil here and the numbering stays the same. So our numbering hasn't changed. We have +34 25 and one six and again the whole point of fermentation is just to keep, like Hollis is going by regenerating n a d plus. All right with that, let's turn the page.