[Music] is [Music] [Music] [Music] br [Music] do [Music] came into my room [Music] you matter [Music] [Music] [Music] [Music] class chapter was it Monday Wednesday on chapter 6 um last week past Wednesday this past Wednesday was chapter 7 oh it was this we're going to finish this today yeah chapter 7 arm cellular [Music] respiration all right guys happy Friday um all right so last full week before you guys get fall break anybody doing anything fun Pocky working yeah I'm I've had the uh exam the second exam scheduled before break so you guys don't have to study over break um and a couple of announcements so your fourth quiz is going to be on Monday um so it'll be on chapters six and seven there's only going to be two questions from chapter 6 and eight from chapter 7 um cuz we only did a couple section on chapter six um and your second exam is going to be on Wednesday the um yeah so that's going to cover chapters 5 through 8 um and it's not every section in those chapters just the ones that I discuss don't know if you guys saw already but I did upload a study guide for this exam so I hope that helps um and um yeah so that should help um also I did send out a message that I created a discussion board Forum so that over the weekend if you guys have any questions as you're studying um you can post them on there and then you all have access to it you all can ask each other's questions I guarantee if one person has a question more than one person probably has that same question so it it's a good way for you guys to like learn and help each other out and then I'll also monitor it so I can jump in and answer questions as well but I think that's a good good really good learning tool so take advant of that um all right so today we're going to be finishing up chapter 7 um these last two sections and where we ended off what on Wednesday was the citric acid cycle so if you remember glycolysis happens in the cytoplasm you get pyruvate from um from glycolysis and the pyruvate has to before can enter the citric acid cycle has to be oxidized into acetal COA so um citric acid Cycles in the mitochondria and that basically um in one of the processes of the citric acid cycle um you end up having energy being produced and so that's what we're going to be talking about it's this production of all this ATP um but what you should know is this key takeaway that each acetal COA molecule that enters the citric acid cycle will release two molecules of carbon dioxide it also reduces 3 nad+ to make three nadh molecules it also reduces one fad molecule it's just another electron carrier just like nad+ um and it does that it gives those electrons to fadh2 and there's one ATP that's produced from the Calvin cycle so this is the celvin cycle yield or citric acid cycle sorry I was working on Monday's lecture we're going to be talking about the Kelvin cycle um another thing you should know is that you have to it's a cycle so you have to continue to regenerate that four carbon oxelo acetate so that you can bind that with the carbon dioxide molecules to make um the six carbon molecu so this is the citric acid cycle yield um but what if we put it all together from the beginning from the beginning of glycolysis when glucose itself is being uh broken down so the glucose yield is six carbon dioxide molecules 4 ATP 10 nadh 2 fadh2 and um and basically so that's the glucose yield now from these nadh and fadh2 you know I've been throwing around these terms a lot and the fact that they're electron carriers but what does that mean what is what do they do with all that energy that those electrons are carrying those basically proceed to the electron transport chain um and so there's an electron transfer of energy you don't have to know this 53 kilal per moles um but essentially this energy from this electron trans transfer is put to use to manufacture ATP so um that's kind of like an over where we're at where we're going are there any questions on this I'll give people a second to catch up on notes all right so let's get into what the electron transport chain is so you'll see that um over here we have the mitochondria um but the electron transport chain is actually embedded in the inner mitochondrial membrane so it's inside of this phospholipid Bayer membrane not everything else happens there that's that's just where this um electron transport chain is occurring and that's where ATP is being produced so it's in that inner membrane um and so it's a series of membranebound electron carriers um and so basically what happens is electrons from nadh and fadh2 are transferred to different protein complexes there's three here um and so the electrons are being transferred and as the electrons are being transferred there's protons that are going to be pumped into this intermembrane space as a result because remember electrons are negatively charged protons are positively charged so um they kind of move together so you're going to be pumping protons As you move these electrons um these protons though have a very important role um we'll talk about that here shortly but this um they move over here and they are able to go through this ATP synthes um so they Supply the energy for ATP production um and so you don't have to know like the Q here or the C which are these um intermediate electron carriers um but you should know you don't need to know also like what the names of these um complexes are uh what you should know essentially is that nadh and fadh2 are electron carriers and they pass them through these three complex proteins that are within this interior inner mitochondrial membrane um so and and that allows for an accumulation of protons in that space um for ATP production so let's kind of go through this step by step um the high energy electrons are transferred by these mobile electron carriers um between these three complexes of the proteins and then the three proteins they use some of the energy from the electrons to pump those protons out of the Matrix and into the inter m space um the electrons are finally delivered to oxygen which forms water so if you remember when we talked about aerobic respiration we said aerobic means that oxygen is um is included there is oxygen and oxygen is the final electron acceptor so that's at this step so it's the final electron acceptor to produce water um in anerobic respiration there is no oxygen available so do you does anybody remember what the final electron acceptor in anerobic respiration is organic molecules organic molecules yeah remember that so what happens to these protons this creates a proton gradient a really high concentration gradient of protons across this inner membrane um and it's a form of potential energy that can be used for this ATP synthes enzyme remember Ace means it's an enzyme um so this ATP synthes enzyme couples the re-entry of protons to the phosphorilation of ADP to form ATP so what that means is um you have this concentration gradient of protons now protons are positively charged and they're not going to be able to go through through this membrane and that's because remember these are hydrophobic so they fear water water is polar so anything with a charge is also going to be um not able to just pass right through right so you usually need a Channel or a carrier um to diffuse it through um and so it's going from higher concentration essentially to lower concentration so it is a type of diffusion but the point here is that um the energy from these protons go through this ATP synthes provides the energy that's needed for the phosphorilation of ATP to make ATP so I'm going to repeat you know this several times um this whole process that I just described is called chemiosmosis it involves the accumulation of the protons in this intermembrane space driving the protons into the Matrix via diffusion most protons can only re-enter the Matrix through this ATP synthes because of what I described of this um imp impermeable varer and the energy grad gradient that's from these protons it's what's used to make ATP so all of those electrons in the previous steps that were carried from NAD plus to nadh to fad to fadh2 all those electrons those all have energy and so those have been carried out through the mitochondria through all these processes and then they have to be put to use in some way and so this is where this energy is put into use and it's to make ATP that's the ultimate goal of of the cell um so this ATP synthes is what carries out um this the synthesis of ATP um and so over here we have these two proteins essentially a channel this is a channel and this is a rotor um and so protons that travel through this one channel essentially causes this rotor to rotate and it basically pumps the protons out this way and that energy is used to make ATP any questions there all right I'm going to play a couple of videos here that helps explain this all together when glucose is oxidized during glycolysis and the CR cycle the co-enzymes nad+ and fad are reduced to nadh plus H+ and fadh2 in the mitochondria the electrons from nadh plus H+ are transferred to the electron carrier proteins and the protons are transferred across the membrane as the electrons move from cytochrome to cytochrome down the electron transport chain more protons are carried AC across the membrane cytochrome C transfers electrons to the cytochrome C oxidates complex protons are also transferred to the outside of the membrane by the cytochrome C oxidase complex the cytochrome oxidase complex then transfers electrons from cytochrome C to oxygen the terminal Electronic Center and water is formed as the product the transfer of protons generates a proton motive Force across the membrane of the mitochondria since membranes are impermeable to ions the protons that re-enter the Matrix pass through special proton channel proteins called ATP synthes the energy derived from the movement of these protons is used to synthesize ATP from ADP and phosphate formation of ATP by this mechanism is referred to as oxidative phos correlation all right so once again you don't have to remember the names of those enzyme complexes but you should know that there are three proteins that the electrons go through proton pumps yeah so the next one is on proton pumps so I'll play this one but do you guys have any questions on the electron transport chain proton pumps are protein complexes that move the protons generated during oxidation reactions across the cell membrane as the protons move through the proton pump they begin to build up on the outside of the membrane the protons accumulate on the outside of the membrane creating a concentration gradient the membrane is not permeable to the charged hydrogen ions and they cannot diffuse back across the membrane instead they must pass through a special channel the protons move through this special Channel which is the enzyme ATP synthes this enzyme uses the energy derived from the movement of these protons to convert ATP into ATP the movement of protons down a concentration gradient provides the energy for ATP synthes to form ATP this mechanism of producing ATP is called chemiosmosis okay so kind of just a more detailed version of the proton pump questions all right so this is kind of the entire um reactions of aerobic respiration in the mitochondria um so some important things this is just a really good overview some important things things to know for the exam is um where these are happening um what's coming out of them what's the product uh where ATP is formed and then you'll see that the majority of the ATP is coming from this ATP syas so um although there is some ATP that's generated in glycolysis and in the citric acid cycle the majority of that energy is harvested to end up making it here to make most of the ATP through the enzyme that that synthesizes ATP um you should know where everything is occurring so in this Matrix or this yeah this Matrix here this is um the B layer the phospholipid B layer that's where the electron transport chain is um you should know you know glucose is in the cytoplasm and that kind of thing um so yeah with uh aerobic respiration you start off with glucose and oxygen and then you end up making CO2 2 water and ATP so you should know where those products are being made in the process does that make sense so in total the theoretical energy yield of all of these reactions is about 30 32 ATP molecules per glucose for UK carot so one molecule glucose produces 30 ATP so that's very very efficient and clearly you know it's a great way for ourselves to yield energy um and so we need this uh to function and to work all right so that's the end of cellular respiration are there any questions here okay we are going to jump right into a little overview that I have of photosythesis and on Monday you'll have your quiz and then we'll continue with photosynthesis so um I guess first I want to take you back to several hundred years ago where plants were thought to obtain their food from the soil so they literally people thought that they were literally sucking up um food from their Roots um and so this Belgian scientist Han Baptista vanmont um the 15 and 1600s he planted a tree in a pot of soil and he weighed the contents the soil was 200 lb the tree was 5 lb so he decided okay I'm going to water this plant and I'm going to wait 5 years um and so he did that and after 5 years he he did this same thing he took the measurements and he saw that the soil was 190 lb and the tree was 169 lb so initially the theory was that the food the entire tree is growing because it's taking up nutrients and things from the soil so you would expect that the soil to be a lot less here um but it's not it's generally this about the same but the tree is 164 lb heavier obviously so where is all that organic material coming from where is the tree you know coming from in order to to grow so um he actually incorrectly concluded that the water that he added mainly accounted for the plants increased biomass um but you know this biomass it's organic so it's carbon based so where are we getting this carbon based tree from and so many years later other scientists discovered that the carbon SCE was coming from somewhere else um it was the carbon dioxide that was coming from the atmosphere that was contributing to this growing biomass of the tree so that's how photosynthesis was discovered um just a little history there um and so if you think about it you know we we always say that photosynthesis basically you take water and carbon dioxide and sunlight energy and then you make oxygen and a carbohydrate so the carbohydrates are coming from carbon dioxide in the atmosphere which is really cool if you think about so a quick overview of photosynthesis it's a vital process in which green Plants algae some bacteria convert light energy into chemical energy in the form of glucose um this process is essential for life on Earth and um the photosynthesis is obviously as you know it serves as the primary source of the oxygen that we breathe but also as the primary source of organic compounds things that we eat and and uh metabolize so who does photosynthesis obviously we know plants do there are some a lot of water organisms that actually also do photosynthesis and water organisms make over half of the oxygen that we have on Earth so they're really important um the types of water organisms are like algae uh there's also some bacteria that can photosynthesize like CYO bacteria which I've mentioned before um and they are green they're cyan the color so that's where that comes from because they have um they undergo aerobic photosynthesis um and so photosynthesis actually occurs in a wide variety of organisms as you can see and it comes in different forms and those two different forms are um a form that is an oxygenic so it does not produce oxygen in a form that does oxygenic photosynthesis um and so for the purpose of this lecture we are going to talk about just the oxygenic photosynthesis because that's the form that makes oxygen for us to breathe um but just in FYI that there is an anoxygenic form um and we're also going to just talk about photosynthesis from here on out in the context of land plants all right so um we all know you know that the oxygen that we breathe was made by photosynthesis so here's the chemical reaction um can anybody tell me how this relates to cellular respiration yeah exactly it's it's the opposite yeah so um cellular respiration you have glucose that's being broken down um you put oxygen in and then you make carbon dioxide and water and energy in the form of ATP um photosynthesis is the opposite you have um carbon dioxide and water and sunlight and that makes um glucose and oxygen um one one thing that I always find is that people don't usually put plus light as a reactant but it is I mean none none of that process can actually go without the sunlight so the diversity of life that covers the earth is really only possible because of photosynthesis I can't emphasize this enough it's really important um and all of that is powered by Sunshine so the sun provides the energy that's used by all living cells but that sunlight is captured by plants through this process so plants are very important so can somebody tell me is this a catabolic or anabolic reaction you can discuss with your neighbor cabol you been catabolic what do other people think cabol you think anabolic can does one of you guys want to explain either way did you say no do you want to explain why you think it's uh catabolic because you're harvesting the energy using the energy but then she said okay let's rewind a little so catabolic remember my little analogy of a cat throwing something and breaking it so you're breaking things up so here instead of breaking glucose down we're building up glucose by having six carbon dioxide molecules and you're right in that catabolic reactions you harvest energy which means you get energy on the this side of it but in anabolic reactions you put in energy so to build something up you need to put in energy when you break something down your um releasing energy so in this case you're putting in energy in the form of light um but also you're building up this six carbon molecule from Individual carbon dioxide molecules does that make sense okay so that would make photosynthesis anabolic and cellular respiration catabolic great so where does photosynthesis take place does anybody know where in the plant leaf yeah the chloroplast the chloroplast yeah so here we're going to recall tissue architecture of a leaf um there's a lot of different layers um in in the plant leaf you don't really need to know all of these names um except that there's this thick inner layer called the misop that um has these chloroplasts and so that's it's really rich in chloroplasts and so chloroplasts are organel within the plant leaves that carry out photosynthesis and the chloroplasts themselves have an outer membrane and an inner membrane um and the inner membrane is actually highly organized with these flattened disk structures we call these thids so in the thids is where um and and I guess the space between we call the stroma that's where photosynthesis um takes place so piloid membrane is that internal membrane of the chloroplasts um this is a continuous phospholipid bilayer um that's organized into these sacks they're stacked on top of each other so they're called Grano when they're stacked but what you need to know is that it's the thyo covid membrane they contain chlorophyll chlorophyll is just a pigment um and so there's other photosynthetic pigments as well that help capture the light energy a pigment is just a molecule that will absorb light energy in the visible range so light in the visible range is Roy G Biv red orange yellow blue green indigo violet um and so these pigments capture light and they absorb that light from the sun and what they reflect though is the opposite color on that spectrum and we'll talk more about that on Monday but I just want to give give you guys a little bit of like background so if chlorophyll ends up showing up as a leaf if a leaf is for instance um green then we know that chlorophyll is the molecule that is absorbing that light but the the chlorophyll isn't absorbing green light it's actually absorbing the opposite which is I think red or orange um in that range so um we'll talk about that more next week but um the last thing I want to give you a little overview on because next week we'll go into detail with these photosynthesis occurs in two stages the light dependent reactions and the light independent reactions we call the light independent reactions the Calvin cycle um and so don't confuse that with citric acid cycle like I did earlier and the light dependent reactions they happen in the phid inside of the space in in this membrane the purpose of the the light dependent reactions is to capture light um from the Sun there's two photos systems that do this and the goal here is to make ATP and nadh so ATP is made and NAD or dph the P there is because it's photosynthesis so make sure you also know that nadp plus gets reduced to nadph um and ATP is also made in these reactions and then there's also the breakdown of water to produce oxygen um gas now the oxygen is produced in the light dependent reactions um but why are we making ATP and edph that's because these two are going to be used in the uh the Calvin cycle the light independent reactions so um just like in cellular respiration where you're harvesting energy and you have electron carriers like nadh here it's nadph that energy is going to be used somewhere else later later on in the cycle so here the ATP and NPH are used um by the Kelvin cycle and the goal there is to um convert carbon dioxide from the atmosphere and this is a cycle it runs six times and that way you have the six molecules of or the six carbon molecule of glucose so we know that in photosynthesis if you just think about the equation you have carbon dioxide and water and sunlight and then you are making oxygen and then you're also making the carbohydrates the organic molecules so um it's important to know where each of these is made and then the last thing I want to point is that like I said this is in the phyo covid space um and then outside of that that like liquid area that you that's kind of like the cytoplasm that we call in other cells that's the stroma um and that's where the Calin cycle happens it's not in the actual phid so very similar to how cellular respiration moves through the organel um so any questions on this all right well on Monday we will have our quiz and then we'll uh quickly turn around and get to it because we have to finish photosynthesis before the ex exam on Wednesday um yeah make sure you use the study guide and you ask questions on the discussion board um and yeah keep keep checking that