Organic Chemistry

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24. Carbohydrates


By now you should know monosaccharides and we scratched the surface on disaccharides just a little while ago, but what about polysaccharides



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Hey, guys, in this video, I just want to touch on Polly Sacha rides and highlight a few of the most important Polly Sack rides that you might need to know. Alright, guys. So you guys know what mono sack rights are by now? And you should know a little bit about die sack rides. But what about what we call Paulie Sack rights? If it's more than two, well, they're actually a few different categories that we need to be familiar with. Their very straightforward. This is going to be like the easiest page in your packet, but let's just go through it. Try sack rides so guys try sack rides would be three mono sack rides. Link through oak like acidic linkage is amazing. Ah, legal sacha rides that would be illegal. It's some. So it's anywhere from between four and 10 like a few, but not not on Lee. Three. Its's a little more than three, and then Paulie Sack rides anything that is more than 10 Sacharow. Mono sack rides in length would solidly be in poly sack ride territory. So when you hear something that Polly Sack ride that is a very long chain usually It's a very long chain of sugars that are all linked together through those. Um okay, like acidic linkages. Okay, Now, guys, that's pretty much where the definitions end. And now what I want to do for the rest of this video is just highlight a few of the most important Polly Sack rides that you might come across in your biology major or your chemistry major. Or maybe even in your homework. But this is more just for, uh, just like, the more you know. Okay, So, Polly sack rides that are created by plant specifically for use as an energy store. That's very important. It needs to be used for energy are known as starches. You've heard of the word starch before. So a starch is just the name for a poly sack, right? That's made by a plant, not by an animal by a plant for energy. It's a very specific category, okay. And s I'm going to show you guys some examples of that in a second. And Paulie sack rides can have straight linkages and branch linkages. That's interesting. 14 linkages. We've We've seen these before. Die sack rides. Remember that one for linkages. tend to make these nice straight chains, so they tend to be straight Paulie Sack ride chains, whereas 16 linkages. I'll show you what a 16 linkage looks like in a second, but it's way more bent up. It's gonna make branch chains. So as I'm showing you some examples of common Polly Sack rides, it's going to be in the context of straight chains and branch chains. And just, you know, as I've already alluded to, the straighter the chain, the harder it is usually to digest on. The reason is because it's going to be very gonna be stronger. It's gonna be more dense. It's gonna be more difficult for enzymes to get in there. The more branch it is, usually the easier it is to digest, because it's easier for enzymes and fluids to get in between and hydrolyzed. Okay, cool. So that being said, let's look at some common Polly Sacha rides. And by the way, guys, I'm gonna show you three police Ackroyd's and notice that all I'm looking at here is Polly sack rights of D glucose D glucose de glucose. So it's just funny that, um, it's crazy. How many different types of police Ackroyd's there could be because all I'm showing you right now is D glucose. But if I were to look at black toe sort or whatever other one that you wanna look at, um, you could have different types of Polly sack rights for all the other sugars as well. So just keep in mind, this is just a very limited amount of them, but these are some of the most common. So what happens when a plant makes a long Polly sack ride made of D glucose and beta one four linkages? We've talked about this before. Why do we call it beta 14? Because it is going in the same direction as the stereo descriptor. I'm linking with one in the four. So these are beta one for linkages. We know that this is probably gonna be strong. It's probably gonna be strong linkages, right? Because they're very straight. Does that make sense? Well, guys, this is what we call if you have a beta one for linkage. This is what we call cellulose. Have you heard of cellulose before? Guys, Cellulose is like the fiber of plants. Okay? It is like it's what cotton is made out of its what stems are made of. It's what leaves air made of its what would is made of. It's what papers made out of. It's all made out of cellulose. That sound very appetizing. Not really. So, guys, um why do you think that this would be a good structure for for wood and plants and fibers and all that kind of stuff? Because they're very strong linkages. So does this count as a starch. Do you think that cellulose counts as a starch? Let's go through the definition, we said. Is it a poly sack ride? Yes. Is it made by plants? Yes. Is it designed as an energy store to be digested? No, because those linkages air so strong that they're gonna be very fibrous and very impossible to digest. So this is not I'm just gonna put here, not a starch. Okay. Instead, because it's not an energy store, sell you looks is used for structural support. Okay? It's used for structural support. It's used for cell walls. It's used to give rigidity to the structure. It's not eaten by anything. Well, it could be eaten if you're like a termite or a cockroach. You actually could eat cellulose. But that's off topic there. Some specialized animals and creatures. The canny cardboard. But most animals can't. So that's why this is considered not a starch. Cool. Awesome. So let's go on to the next one. So we see Is that here we have once again D glucose linked together By what types of linkages. You guys should be able to recognize this by now. These air Alfa 14 linkages. Right? So what happens if you have Alfa 14 linkages and, um and it's a D glucose Polly sock. Right. Well, this is going to be called AM alos. Okay. And remember, guys that these are essentially longer versions of your die sack ride. So remember that d glucose Alfa one for linkage would actually mall tose right if it was a die sack ride. But if you keep adding it's not called multi us anymore, it's called AM alos. Okay, so question would am alos count as a starch. What do you guys think? Let's go through the definition. Is it a poly sack ride? Absolutely. Is it made by a plant? Yes. Could this be used as an energy store. Totally because notice that it's made out of Alfa linkages. What did we say about Alfa linkages? You could digest those. The beta ones are kind of impossible, but the Alfa ones are easy to digest Notice There's more kinks in it. It's not quite a straight, so it's gonna be easier to digest. Angelos is one of the major forms of starch, So I'm gonna put here major form of starch. There are other forms of starch as well, but this is one form of starch. Cool. Is that making sense? Awesome. So let's go down to another policy, Ackroyd. That might be important at some point. So what happens if you take d glucose right? And you react? And you? I'm sorry, not reacted. You form a bunch of Alfa 14 linkages just like am alos. So this is very similar to animals. Alfa 14 linkages, right? But every 10 or so sugars you throw in an Alfa 16 linkage and what am I looking at? That's this guy over here, so notice that this is considered an Alfa 16 linkage because this is the This is the carbon. This is the Alfa Why? Because it's going. Let me just use a different color. It's going trans to this stereo descriptor. So it's Alfa. It's at the one position of this carbon. But notice what carbon is it attached to on the other sugar. So this is a This is a an Alfa 14 along with some Alfa 16 That includes branching. Okay. And guy is it turns out that this is another really important Polly sack ride that you might need to know. Called glycogen and guys, glycogen is the main energy store of human physiology. Okay, so whenever you eat a little bit too much and you have too much blood sugar going around on and you have, like, 81 too many Dunkin Donuts, your body is going to take that sugar. It's going to take that glucose and lock it up in the form off Glycogen. Glycogen can then later be used when you're starving or when you're hungry. When you need energy, it can then be used thio to provide energy later to be broken down. So is glycogen a starch? What do you guys think? Is it a form of starch. Uh, it's definitely not a starch because made by animals. So it's kind of like it's like the animal version of AM alos of starch. We have almost the same thing, but we just add a few of those 16 linkages, and now we call it glycogen. Okay, so I'm just gonna put here not starch. Duh. Okay, because it's made by animals and starch can only be made by plants. So this would just be This isn't so. This fills the other criteria. It's a poly sack ride. It is an energy store. But it's not called the starch because that would it's made by animals cool and guys. Lastly am alot pectin is like the plant version of glycogen except instead of having branches every uh, mono sack rides it has branches more like every 30 mono sack rides. Okay, isn't it crazy how plants and animals are so different from each other? Right. But we have these structures that air so similar in function for plants they have am alos, which is a starch am alot pectin. Do you think am alot? Pectin is also a starch. Totally because it is made by plants. It's a poly sacha ride and it's used as an energy store, right? It's like glycogen. It's used as an energy store. It's got Alfa linkages that you can digest and then humans and all animal physiology. We have very similar structures, except that we decided to put our 16 linkages every 10 sugars, which is this minor difference. But it means that we use glycogen and plan to use am alot, pectin and am alos cool. Awesome guys. So I hope that this video helped mono helped Polly separates come alive a little bit for you guys a little bit more and let's go ahead and move on.

Common Polysaccharides: