Oct 4th - Overview of Cellular Respiration

Transcript 0:04 all right let's go ahead and get started here hopefully you had a nice Nobel 0:09 conference good change of pace I watched virtually for my livid room it was 0:15 really a good change of pace for me um some cool speakers some really 0:21 interesting speakers there so we're going to start moving into the content 0:26 for our next unit right I did grade during exams for unit one your scores 0:31 are on Woodle I will hand them back on Monday um I still have a few students 0:36 needing to take the exam so I can't hand them back today but on Monday I will hand them back um I will tell you right 0:44 now there will be a couple opportunities to get some points back all right I will 0:49 elaborate that on that on Monday as well let's see don't think I have 0:56 anything else about the exam I mean overall I think you all did fairly well for your first biology exam even if it 1:02 wasn't the score that you wanted um big thing about this first exam here is that 1:09 now you know my style and how to study maybe how to change your studying right 1:15 it's all about kind of adapting uh speaking of exams I get did 1:20 that poll on when you would like to take the final exam the majority of you said 1:25 last day of classes so it will be last day of classes uh how many 1:33 points depends on how many you got wrong and if you got wrong the right questions 1:39 I'll elaborate on Monday so essentially what I do is I look to see what questions the majority 1:46 of you got wrong and I take that as a key is either I didn't teach it well or the question was written poorly right 1:53 and I give you a chance to earn back points on those questions all right so final exam will 2:01 be on the last day of classes which means you do not have to show up for the final exam days I am in the process of 2:08 um at least for this class I'm in the process of changing our schedule what 2:14 that will mean is that the content for unit four will just be shortened a little bit and everything will be 2:19 shifted a day forwards all right um so I haven't quite changed it yet on the 2:25 schedule but I will in the next day or two here any questions about this results the 2:34 exam pressing questions you have before moving into the next 2:41 unit all right so we are starting content for 2:47 unit two unit two is focused on three topics cellular respiration fermentation 2:56 and photosynthesis right it's only three topics but there's a lot 3:03 of steps in each of these processes all right um so it might be beneficial for 3:08 you it might not be beneficial for you I like this unit because I can study better when I think in terms of 3:15 processes rather than isolated biological terms we're going to start with cellular 3:21 respiration right so today we're going to go over some Concepts we need to understand before we dive into cellular 3:28 respiration um as well as just the broad overview of cellular respiration and 3:34 we're going to start in the first stage of cellular respiration so if we look 3:40 at big overview here we're talking about metabolism all right so metabolism is 3:47 all of those life sustaining chemical reactions in a Cell right whole host of 3:53 reactions a lot of reactions we look at this diagram I like this diagram because 3:59 it shows you just how complex it can become right big picture here is that we 4:06 are converting food energy so what we're ingesting into cellular energy right 4:13 energy like ATP it's a multi-step process it's not 4:18 straightforward it's not you eat food you get energy there's a lot of steps in between and again I like this image 4:24 because they even color coordinated it to what types of molecules you want might be ingesting like carbohydrate 4:32 metabolism is different than lipid metabolism is different from amino acid 4:39 metabolism right so whole host of chemical Pathways 4:45 we're just going to brush the surface we're just going to focus on glucose which is part of the carbohydrate 4:52 metabolism here 5:01 all right so if we look at metabolism like I said there are so many reactions in metabolism but we can categorize 5:08 reactions into two different paths either they're going to be catabolic or 5:14 they're going to be anabolic these are very similar to exonic and endergonic 5:22 reactions so catabolic reactions they are exonic which means they release 5:28 energy they happen spontan ously for breaking down cellular 5:34 components you're taking a larger molecule breaking it down into its 5:39 component building blocks releasing energy in the meantime right so if we look at our 5:46 image up here we have our one large molecule we're breaking it down into its 5:51 smaller units we're releasing energy right and again this is exergonic 5:58 it happens spontaneously so that Delta G is 6:04 negative thinking back to our unit one content versus an anabolic pathway right 6:11 completely opposite instead of breaking down a large molecule now we are building up a larger 6:18 molecule so in animalism we have smaller units right maybe these are all monomers 6:24 that we're going to combine together to create a polymer or a larger molecule 6:31 this is not exonic it's endergonic which means we need an energy source so 6:37 typically we are going to couple energy with this reaction so we need energy in order for this to 6:45 occur so this is important when we think about um synthesizing different 6:51 components for our bodies maybe we're building up a carbohydrate molecule 6:56 right maybe we're building up glycogen to store energy maybe we're making a protein so we have to combine a bunch of 7:03 amino acids together now it's important to note for 7:08 all of these Pathways there is going to be an enzyme coordinating each step all 7:14 right even if that pathway is catabolic even if it's exonic so it happens 7:19 spontaneously there's going to be an enzyme every step of the way can make this go faster right so if you look at 7:27 metabolism you could have to thousands of different enzymes involved here and 7:33 we'll see a few here and there as we talk about cellular 7:40 respiration all right so I want to just kind of elaborate on these two topics just a little bit more it really 7:47 reinforce catabolic versus anabolic so if you look at anabolic 7:55 reactions making larger so we might not get the molecule that we 8:02 need from food right but we can take the components that we've taken in from our food to build up the larger molecule 8:09 that we do need so for example if we look at a protein right the smaller units are our 8:17 monomers right are our amino acids those amino acids will come 8:23 together right to form our polymer of our protein right because we're building it 8:30 up this reaction doesn't just happen spontaneously we need an energy input so 8:36 we need to use energy in this process now the energy that we typically use is 8:42 ATP which we've talked a little bit about but there's another molecule that 8:47 we will talk about today called nadh which is also an energy carrier 8:55 molecule all right so anabolic reactions big picture needs energy we are building 9:01 larger 9:11 molecules all right so the opposite of that would be our catabolic Rees right 9:17 so in this case we're breaking down molecules maybe we are oh we ate a 9:23 potato or something right something really starchy we've ingested some starches we need to break that starch 9:29 down into its component parts and the component part of a starch 9:34 is sugar molecules once we've broken it down into 9:39 its smaller units those smaller units can then be used elsewhere I like this image because it 9:46 kind of shows you different Pathways that this can occur so we might intake our food let's say that's a complex 9:52 carbohydrate here right so like a starch that starch can be broken down into blue 9:59 puts right all that breaking down is our catabolic reactions so all the arrows 10:05 here that are like this green this teal green in color those are our catabolic 10:11 reactions now once we have those smaller units right so once we have all of those glucose 10:17 molecules they can be used in anabolic reactions to build up molecules that our 10:22 body needs right so we have our building blocks we're now going to use our building blocks to produce molecules 10:29 that our body specifically need now in catabolic reactions we don't 10:36 need energy right but we produce 10:41 energy right and so our energy produced again is going to be in the form of ATP 10:47 or 10:57 nadh a lot of different CID again depending on the type of food you're 11:05 ingesting now I have one more image on the slide related to or the next slide 11:12 related to catabolic and anabolic reactions that really simplifies 11:20 things so we're taking in food we're breaking it down we're using 11:26 those components that we have broken down to build up other 11:32 molecules the slide is just really simple shows you broad overview here not 11:37 too many complexities see when we break them down we're releasing 11:43 energy when we're building up larger molecules we're using that energy right 11:48 so they all kind of interplay with one 11:56 another all right let's do a group question I want you to 12:02 tell me of these two um reactions that you see which one is anabolic and which one is 12:17 catabolic yeah 12:39 yeah it's putting it 12:58 together e 13:48 spe 14:14 all right if we look at this first reaction here we're going from cellulose to glucose what kind of reaction is 14:22 this it is catabolic yes I forgot my clicker is not working because I had to charge my computer 14:29 all right catabolic right we're breaking down a larger molecule into the smaller 14:35 components of glucose which means that this one's catabolic you know the other one has to be anabolic yes we're 14:44 building up a larger molecule in this case we have two nucleotides that are 14:50 combining together to starting to form a strand of DNA 14:55 here all right 15:01 I know we've talked about ATP but because cellular respiration is all about producing at is worth coming back 15:09 to and talking about it in a little bit more detail um I noticed this mistake in my 15:17 last class I grabbed this picture from the internet thinking oh I really like the Simplicity of it this picture has a 15:24 mistake on it um has anybody SE a mistake 15:31 you don't if you look at the molecule here it says that this sugar is a ribosome it's not a ribosome right um so 15:40 if we look at ATP it's really similar to an RNA nucleotide and that it has a 15:46 ribulose sugar not a ribosome a ribulose sugar connected to a base that base is 15:53 going to be aine connected to three phosphate groups 15:59 instead of only one that we see in RNA all right so this image I did not look 16:04 closely enough at ribosome is wrong we know that's an organel it should be ribulose for ribulose 16:11 sugar all right so it's really similar to an RNA nucleotide in its structure 16:16 the big thing here is that it has three phosphate groups and that's key so these 16:22 phosphate groups they have a lot of negative charges and we're trying to force three 16:29 of these together and in fact we have forced three of these together they are bonded together in this 16:35 triphosphate part of our ATP okay and we know like charges repel each other and 16:41 we have now forced these like charges to bond really close to each other what 16:47 that means is that those barns have a lot of potential energy those B groups 16:53 naturally want to repel each other right so we have a lot of potential energy in 16:59 those bonds when those bonds are broken we release that energy and that is the 17:05 energy that we actually use to power a lot of our cellular functions right so energy is stored in 17:13 those phosphate bonds now when we take away a phosphate 17:21 group right via hydrolysis right we release energy 17:29 we release a phosphate group and what is left is our a 17:34 molecule adenosine D phosphate D meaning two because now we only have two 17:39 phosphate molecules okay this one does not carry as much energy right in order for a DP 17:47 to be utilized we have to add another phosphate group which involves energy we 17:53 have to add an energy add in a phosphate group to bring it back to ATP 18:00 but the big picture is that ATP is not really used up it's just part of this cycle ATP ADP the ATP the ADP right it 18:10 just Cycles those three phosphate groups are 18:16 really 18:21 key all right so we have ATP but we also have nadh 18:30 na is also a molecule produced in cellular respiration that carries energy right 18:38 but it does this in a different way so in ATP that energy is held in those 18:45 bonds between the phosphate groups in nadh this molecule carries energy it 18:54 carries energy in the form of electrons and protons right so it's not bound in a bond but 19:01 rather it's energy in the form of it being able to carry electrons and protons right so we would call it an 19:08 energy intermediate in that it can accept electrons and protons removed from other 19:17 molecules so nadh is our one on our right hand side here right if we look at 19:25 it carrying these electrons carrying these protons we see that show up on the top of our 19:32 molecule we see this one has two h's it has a ring of carbon with only 19:38 two double bonds and it has a nitrogen with no charge right so this one is currently 19:45 carrying energy when nadh releases that energy 19:52 releases the protons releases the electrons it turns them into NAB plus 19:58 right and again the change here occurs where we only now have one 20:04 hydrogen instead of two double bonds we have three double Bonds in this ring of 20:09 carbon and our nitrogen has a positive charge right so the molecular structure 20:16 that is what is physically changing between nad+ and 20:24 nadh now this molecule is useful in that it carries the energy 20:29 in the form of electrons and protons and they can donate that energy in the form of electrons and 20:35 protons now nadh is one of those that I feel like you probably haven't heard about as much a lot of the focus is 20:42 typically on ATP so I just want to have it reiterated to you right so the next slide here uh 20:52 is just a review I want you to review how do each of these molecules provide energy right 20:59 and then think back to our last unit what organal is going to play an important role in cellular respiration 21:06 which is a topic we're heading into 21:49 and then en 22:27 you e [Music] 23:25 feel feel like I don't 24:15 all right how does ATP provide energy for a cell how 24:21 specifically does it do this 24:35 yeah yeah it's all held in the bonds between our phosphate groups right so we're holding that energy in our bonds 24:42 now what about nadh how does 24:49 nadide yeah it vares electrons and proton right so instead of holding energy in its bonds right now it can 24:56 transfer energy by transferring electrons and protons all right so we're moving into 25:04 cellular respiration talking about making a lot of ATP what organel is 25:09 responsible for this mitochondria yes good little review question 25:17 there yes my La last class did that too I forgot I need to pause on this slide 25:23 so HP holding it in bonds nadh is a electron carrier 25:29 carries it for it I've seen the analogy for nadh in 25:35 fact I think I'll actually put this meme on a future slide uh if you think about Lord of the Rings where the ring is the 25:43 energy right Sam cannot carry the ring froto carries the ring but Sam can carry 25:49 froto all right so it's an energy carrier if you're a little bit nerdy 25:55 like I am and if not maybe that went totally over your head and that's okay there are other analogies I'm 26:04 sure all right are we good with this 26:10 slide I'm going to take that as a yes all 26:18 right all right one concept we have to go over before we really dive into 26:24 cellular respiration is redo reactions right again this is not a chemistry class so 26:31 we're going to stick to surface level knowledge here right and honestly redo 26:36 reactions are not my favorite thing to teach because I think it just it feels Mony to me but nonetheless we are going 26:44 to learn redo at a very surface level here so these are reactions involving 26:49 electrons being transferred right so nadh we know it carries electrons and can transfer electrons this is involved 26:57 in a Redux reaction action when a molecule is oxidized or 27:02 goes through reduction right we're removing 27:08 electrons did I say that wrong I think I 27:14 WR so oxidation removal of electrons right reduction on the other hand right 27:21 is the addition of electrons which that definition is a little counter and two 27:28 right if I'm reducing something it doesn't seem like I should be adding something but what I'm reducing is the 27:35 charge right I am adding electrons which have a 27:41 negative charge so I'm reducing the overall charge of that molecule of that 27:46 atom right so if we look at our example here I have molecule A and 27:52 B molecule a has an extra electron it's going to transfer it to 27:59 we would say a is oxidized because it's losing its electron and B is reduced 28:05 because it's gaining an electron and the pneumonic that I always have to repeat in my head to remember 28:11 this is oil bra right oxidation is loss 28:16 reduction is gain and we're talking about 28:22 electrons all right so we're going to go from talking about this simple redo reaction we're going to 28:29 scale it up quite quickly so my next slide here we're 28:36 going to talk about the overall equation of cellular 28:43 respiration all right so in cellular respiration we're taking a glucose 28:48 molecule and an oxygen molecule and we're turning it into CO2 28:55 water and ATP now if we're just focusing on Redux 29:02 reactions right often hydrate ions are going to accompany those electrons so if we look at glucose 29:09 glucose is losing hydrogen to become carbon dioxide so you can say glucose is 29:15 being oxidized versus oxygen on the other hand is going to gain some of it all hydrogen 29:22 ions to become water so this would be reduced 29:29 now we could look at this in a different way to see specifically how the electrons 29:36 change which is what the second image is all about same reaction just a different 29:42 way of looking at it and here what this image is emphasizing is that not only are we 29:49 losing and gaining electrons right but that can change the nature of a molecule 29:56 right so if we look at glucose we have the CH bond this is a nonpolar 30:02 calent Bond electrons are shared equally but when we lose these electrons 30:08 and transfer the hydrogens right when it becomes CO2 30:14 those oxygens are now held more closely to oxygen and it's part of a polar F so 30:20 these Electro negativities can change as well right but I want you to really focus on big picture here right I want 30:27 you look at the removal and the acceptance of electrons to know which is being reduced which is being 30:34 oxidized and I think the best way to do this um is practice right I thought I 30:40 had my practice slide next I don't um I also put in the slide of nadh not that I would expect you to know 30:47 this specifically right what I want you to know about nadh is it's a carrier electron but if you're curious to see 30:54 specifically how it carries it we look at this uh nicomide I always have trouble saying 31:00 this word um molecule part of the molecule up here right and it can be 31:06 reduced and oxidized back and forth and it's all about those two electrons those 31:11 two hydrogens all right now let's practice so I want to uh look at this equation 31:19 and try to figure out which of the reactants right so first part of the equation is being reduced and which are 31:25 being oxidized give it some thoughts and then we will go over this um together 31:58 the two plus charge and then 32:03 two CR 32:56 all quiet did we all figure out 33:02 already answer all 33:10 right that's exactly right right so CR I believe it stands for chromium is 33:17 oxidized SN I can't think of the atomic um label for that one off the top of my 33:23 head um but that one is being oxidized let's look at why 33:28 is it tin oh it's tin something I would not have thought of off the top of my head so let's let's break this down for 33:35 those of you that might be struggling and I will make this part of the slide available after class if we look at our 33:43 chromium here it's already an ion because it has a positive charge it has 33:48 a positive charge so it means it's already lost an electron there's one more proton then there is negatively 33:55 charge electron we're going to this 3+ 34:01 ion which means we're losing even more electrons right so now we have three 34:08 more positively charged protons than we have electrons which makes it an overall 34:14 positively charged at all right so we have lost more 34:21 electrons opposite is true for 10 right so we're starting with an ion that has 34:27 four fewer electrons than protons right which makes it overall a positively 34:32 charge and that positive charge is going to be a four plus and it's going to a two plus ion 34:41 right which means it's gained two electrons right now it only has two more 34:47 protons than electrons rather than the four more protons than electrons so 34:52 let's gain some electrons back right increasing that charge a little bit 34:58 there we go um any questions on how this is done 35:04 again we're really sticking to Basics not chemistry class we're not trying to 35:10 um make equations equalize and all that fun 35:16 stuff all right I'm going to make that part 35:22 available afterwards so you don't have to write down everything um so let's 35:27 move on on to metabolism again so we have all of these Pathways 35:33 right a lot of different redox reactions a lot of anabolic a lot of catabolic 35:38 reactions the cell has ways to regulate which of these Pathways actually happen 35:45 and which don't one way is by simply turning genes 35:50 on or off right so this would be taking DNA transcribing it translating it to a 35:57 protein right and the cell can control whether or not a portion of that DNA is actually 36:03 turned into a protein right we'll get more into the nitty gr details of that 36:09 in I believe it's the next unit another way that I can regulate 36:14 whether these Pathways will happen or not is just simply cells communicating with one another so cells signaling 36:22 right so one cell signaling that maybe it needs more of a molecule or maybe it 36:27 has too much of a moment the one that I'm going to elaborate on is this biochemical 36:36 regulation and this is where we have feedback inhibition so if we have a pathway right 36:43 maybe there's multiple steps multiple enzymes involved it produces a final 36:49 product when that final product accumulates to a point where we no longer need it it's that final product 36:57 that will inhibit the production um in the first step of the pathway and kind 37:02 of inhibit itself from being made right my next slide is going to 37:09 have a visual that'll help you understand this a little bit 37:15 better right so genes can be turned on or off cells can talk to one 37:21 another or we have febag inhibition where the final product kind of regulates itself 37:34 so if we look at feedback inhibition here all right we're going to look at this fictitious example we have this 37:42 pathway consisting of an initial substrate two intermediates a final 37:49 product and three enzymes that move this path along enzyme one will take in the 37:58 substrate and a reaction will occur we will now get our intermediate product 38:04 that intermediate product will be taken in by enzyme 2 a reaction will occur and 38:10 we'll get our second intermediate our second intermediate is 38:15 taken in by enzyme 3 a reaction occurs we get our final product right great you 38:23 want to produce this final product but there comes to a point where we no longer need as much of that final 38:29 product we have to kind of turn this pathway off when this final product 38:34 accumulates to that level this final product will go back to enzyme one and 38:41 will combine with enzyme one in a site that we call an allosteric site so it's 38:47 not the active site but rather an allosteric site see in this image it's 38:53 kind of opposite the active when it binds to the enzyme in that site essentially that enzyme is 38:59 going to change its shape and we know shape equals function the shape is changing it can no longer bind with the 39:06 initial substrate it basically shuts down the path now when we need to produce more of 39:11 this final product again the final product can be released right and the pathway can move along just like it did 39:21 initially there are many many examples of this in our human body 39:27 right because as humans we need to regulate so many different substances and 39:35 processes so I've designed this next slide just for you to kind of think about what you've learned so far ask me 39:42 questions if you need to and then answer this very easy question what do we need to regulate in our bodies right there 39:49 are so many answers we could have for this 40:26 all for 41:25 a 41:55 know 42:06 some 42:54 I don't know all right first of all any questions come up about the material 43:01 that I can answer all right we're all Pros already 43:08 I like it so what are some processes or substances that we need to regulate in 43:14 our human body blood sugar 43:21 oxygen temperature water salt so many different things I 43:27 don't know about milk can we say milk oh alcol I mean your body has toate 43:33 that too right now Liber plays a huge role so we're regulating all these 43:38 different things and a lot of times regulation will come in the form of feedback inhibition and other times 43:45 there's other ways the body can manage this all right well now let's dive into 43:51 cellular respiration right so overview of cellular respiration is the the 43:57 process by which living cells obtain energy um from organic 44:03 molecules right so the process by which we take in food and that food is broken 44:08 down to give us molecules of ATP and 44:16 nadh now part of this unit is also going to be about photosynthesis because they go hand in 44:22 hand right if we look at this image we see we have our mitochondri 44:27 producing our ATP but it's also producing CO2 in water which then 44:33 chloroplast will utilize to produce oxygen and glucose which then the mitochondria will utilize right and it's 44:40 this NeverEnding cycle now a lot of times people think plants have chloroplasts animals have mitochondria 44:48 right but plants also have mitochondri right uh there are parts of the plants 44:53 that don't photosynthesize that need to use cellular respiration as well but it's often overshadowed by the fact that 45:00 plants can photosynthesize all right so cellular 45:06 respiration we're cleaning energy okay our primary goal is to make 45:14 ATP and nadh now we're going to look at aerobic 45:21 respiration which means we are um going through cellular respiration in the 45:28 um process oh aome that word is like godone for my mind where oxygen is also 45:34 available right so we have oxygen so aerobic respiration we have oxygen we're 45:40 using oxygen right we're consuming oxygen and we'll see when we talk about 45:45 the steps here we'll eventually produce CO2 that will be released now this is a nice um diagram 45:54 of all the steps and we're going to go through these steps and we see that glycolysis is this first 46:01 step now glycolysis can also be anerobic which means no oxygen right so 46:08 glycolysis can happen if there's oxygen and if there's not any Oxygen if there's no Oxygen it's going 46:16 to produce 2 ATP and that's the end of the 46:21 process if there is oxygen it's going to continue in on the pathway 46:27 and will eventually produce around 36 ATP so much more ATP is produced in the 46:34 presence of oxygen as we talk about cellular respiration we are going to talk about 46:41 it in terms of glucose right because it's the most common example um you see 46:46 it very often right other types of molecules will go through cellular 46:51 respiration in slightly different variations we're going to look at the glucose molecule 46:59 all right so our cellular respiration first step is 47:06 glycolysis there's actually three more steps afterwards that we will get to on Monday right so first is 47:14 glycolysis the next step is called the breakdown of pyate then we have the citric acid cycle 47:21 then we have oxidative phosphorization if we were to take these four pathways and generalize it into one 47:28 equation you would get glucose plus oxygen yields carbon dioxide and water 47:37 right but there's many more steps in between to get to that now we're going to start by talking 47:43 about glycolysis today right and then we'll come back to the other 47:55 three all right so we look at a different way to visualize these 48:01 four steps we can look at where they are 48:07 occurring so it's those same four steps that were listed on the past slide we have glycolysis breakdown a pyate citric 48:15 acid cycle and oxidative phosphorization glycolysis is the only 48:22 one of these steps that does not happen in the mitochondria 48:28 right it happens in the cytool it happens outside of the 48:33 mitochondria the rest of these steps will happen in the mitochondria but glycolysis happens in the cytool and 48:40 that's I think the big takeaway from this image at this 48:45 point all right so glycolysis happening in the 48:53 cytool that is stage one of cellular respiration and like we mentioned glycolysis can 49:00 happen with or without oxygen if there is no oxygen we will end 49:07 at glycolysis if there is oxygen we will move on to the next three 49:13 steps now glycolysis is um really identical in almost all living species 49:20 it's highly conserved in its Evolution right meaning no matter what origin we 49:25 look at it's going to be nearly identical in every organism it's always going to contain these basic 10 steps in 49:33 three different phases we look at glycolysis in humans versus the fruit 49:39 fly right they're going to be nearly identical now we do have these three 49:44 steps right we have energy investment right that should give you a clue that we're using energy we're investing 49:51 energy in this this stage we have cleavage which which is 49:56 where we're breaking apart we're leaving apart a 50:01 molecule and then we have energy Liberation right where we're liberating energy we're releasing energy from 50:16 molecules now there's a lot going on here we're just starting with glycolysis 50:21 and we're going to see this a lot of steps here there's 10 steps right I 50:26 don't expect you to know the specifics of all 10 steps but as we're learning cellular respiration pay attention to 50:33 any molecules that I might have folden these are molecules that I would expect you to 50:45 know all right let's dive in stage one 50:50 energy investment in this stage we are using energy we are using molecules of 50:58 at we look at our diagram here we have our glucose molecule that we're going to 51:03 start to break down right it goes through the first three steps in this 51:10 phase right and within those three steps we are using two molecules of 51:17 ATP now at the end of this first phase we get a molecule called fructose 16 by 51:25 phosphate so stage one energy investment 51:34 stage we are using energy and we're turning glucose into 51:39 fructose 16 by 51:50 phosphate now if we look at fructose 16 by phosphate we notice it has six 51:59 carbons as we go into our next stage 52:05 here right into the cleavage stage we are cleaving this molecule apart right 52:12 we're going from one six molecule or six carbon molecule into two three carbon 52:21 molecules right so we have just created two molecules right and that molecule this 52:28 called glycer alahh 3 phosphat so from one glucose molecule we 52:34 get one molecule of fructose 16 by phosphate then we get two molecules of 52:41 glycer aldhy 3 right so now we have two of these 52:46 molecules two glycer alide three phosphat that are going to continue on 52:51 in this next phas 52:59 all right so we have our two molecules continuing on our last phase 53:10 here is our energy Liberation phase this is the last phase of 53:19 glycolysis the last four steps in this 10 step series 53:26 this is where we're taking those two molecules of glycer alhy 3 53:32 phosphate each of those molecules are going through steps 6 through 10 on 53:37 their own in those steps we are releasing energy right this is where we get the 53:45 net production of ATP and nadph this is where we're producing ATP 53:52 this is where we're producing our nadh for each one molecule I'm going to 53:57 abbreviate this so I don't have to keep saying berer alhy 3 phosphate I'm going to abbreviate it to 54:03 g3p for each molecule of g3p right we produce two molecules of 54:10 ATP and one molecule of n okay now we're thinking about this in 54:16 terms of a glucose molecule one glucose molecule has produced two 54:22 g3p right which individually go on through steps so Al together one 54:29 molecule of glucose produces four ATP and two 54:37 nadhs now the end product here is this molecule called 54:43 pyate this is the last product in glycolysis before we move pyate into the 54:50 mitochondria and continue on with cellular respiration 54:59 all right glucose using some energy to get fructose 16 by phosphate one 16 by 55:07 phosphate is cleaved into two and we get two molecules of glycer alide 3 55:13 phosphate which then through a series of reactions turns into pyate and releases 55:19 ATP and nadh so on this slide here it really 55:26 just kind of combines the last three slides together right but the big 55:31 takeaway here is that our net yeld is only two ATP right so I said we produced four ATP 55:40 right which we do but we use two of those in that first step right so we're 55:47 only really producing two ATP that the cell canuse now we're also producing two naad 55:54 agents right often n forgotten about I forgot to put it on my slide I should 56:00 also say that the net yield equals 2 ATP and 2 56:11 nadhs all right we still have five minutes here 56:17 let's answer this last question before we leave I have given you a simplified 56:22 diagram of glycolysis that's missing some of the intermediate molecules I want you to fill in those molecules and 56:29 then tell me where does this process occur in the 56:41 cell you could think of as phases but the molecules produced in each of the phases 57:16 right 57:55 better 58:07 I 58:55 I 59:00 I get the sense that we both so what is this first blank 59:06 supposed to be yeah fructose 16 by phosphate all 59:14 right that fructose 16 by phosphate is going to become two molecules of this next blank which is 59:26 yeah g3p or right uh glycer alahh 3 59:33 phosphate and then that's going to go produce some ATP produce some nadh's and 59:38 that end molecule after glycolysis is done is called what pyate and where does this all 59:50 occur in the cytool outside of the mitochondria yes all right all 59:57 right no homework for Monday content check three has been posted you've been 1:00:02 started but we have not covered all the content on it yet um Nobel assignment is due tonight