Chromosomal Mutations: Aberrant Euploidy

Hi in this video, we're gonna be talking about chromosomal mutations specifically. Apparently. So the chromosomal mutations, what is that? That's mutations referring to entire chromosome sets. So this can be a mutation that describes the change in chromosome structure. So you know how big it is, how small it is, how many genes it has on it and or it can be the number of chromosome copies. So we're not talking about individual gene mutations. We're talking about the entire chromosome and that being mutated, two more copies or having a weird structure. Now there are two types of chromosome mutations. The first is a parent employee, which is what we're going to talk about. And this is going to be changes to the whole set of chromosomes. So for us and instance, that would be if every single one of our chromosomes had an extra copy on it, the whole set of chromosome, it's not just one, it's the entire set. So it would be a parent employee. And then there's a second type which is an employee and this is changes to a part of a single or few chromosomes. So this is something for instance, like down syndrome, which has an extra copy of chromosome 21. So that would be example of an employee because it's only affecting that one chromosome and not the entire set of chromosomes in an organism. So the first one we're gonna talk about is a barren employee and like I said, there are a number of different ways to describe these various types of chromosome mutations all classified under a parent employee. Now these videos are going to be heavy and vocab, right, I'm not going to be walking through math or anything like that, but it's going to be a lot of vocab words that you're and they're sort of just slightly different. It's gonna be hard to memorize them, but you're just gonna have to memorize these vocab words to understand these chapters. Um, so the first one, the first vocab board is deployed, which is where we get this term from up here. A parent employee and employee describes organisms with multiples of the basic chromosome set. So humans are deployed, right? Or we have two copies of every chromosome. Well, we would be described as employed or an individual would be described as employed if they had three copies of every chromosome set. Um, and it can contain more or fewer numbers. So, um, I describe that as, you know, if we have an extra one, but if we have only one copy of every chromosome, even though we wouldn't survive that theoretically if a human only got one copy of every chromosome and still survived with that, that would be called deployed. Now you may say, oh my gosh, how do organisms even survive like this? Well, a lot of times these are things happening in plants which are a little bit more flexible with their chromosomes than humans are humans are pretty much, you know, we have to have this chromosome set with a few exceptions. Um, but it does actually exist in some animals, including amphibians. Amphibians are pretty can commonly have you employed species. And then so this is actually a common thing where the entire chromosome set either has extra chromosomes or less chromosomes. Now there's a special term for monopoly Lloyd, which is a normally deployed organism that contains only one chromosome set. So this is the example I used before and this is the special term for it. So if humans, if there was some individual who just lost half of their chromosomes and so only had one copy of every chromosome instead of two, we would call the mono ploys. And this is different from half Lloyd wright because half Floyd, they have one chromosome set, but they're supposed to, that's what they're supposed to have. Whereas mono ploys are supposed to have two copies but they lost one of every chromosome and so now they only have one. So there are two different terms. And it's important to understand the difference now for some of the organisms who do this, who are things like these wasps, ants, um can be mono ploy aids. And when they are they can undergo this process called parthenogenesis and this is the development of an unfertilized egg. So this is just an egg. It contains half the chromosome set. So it would be a mono ploy, I'd write or half Lloyd. It contains half the chromosome of um what it should of a deployed organism, But it actually develops with out fertilization. So it should be deployed, right? You have an egg. It's hap Lloyd and you should get a sperm that's hap Lloyd and they should come together fertilized and create that deployed organism. Well, in part the genesis, what happens is you have that egg and it's hap Lloyd but it doesn't get fertilized but yet it still develops into an organism. And that organism's mono employed because that the species is deployed but that individual is actually only contains half of that chromosome set. And these are examples of these wasps, ants. These are kind of colony animals type things or colony insects anyways. And so that is part a genesis. So here's an example. Um So here's a deployed organism. We would call it deployed if it got a third copy of every chromosome. So you can see here we have one chromosome set to three black, red and blue. And then Tripp Loyd, which I'll give you this term in a second. But this would be a you employed where it gains an extra. Um It also be deployed to lose it. But we give these a special term unemployed when they contain only one copy of a one copy of the chromosome and they should contain two. So polyp lloyds have more. Here's another vocab word here, polyp lloyds have more than two chromosome sets. So these can be Tripp Loyd if they have three copies. Tech deployed four copies pin deployed five copies hex deployed six copies and so on and so forth. With all the different prefixes for the different numbers. Now These are also employed, right? Employees just describe an abnormal chromosome number. And Polyp Lloyd's refers to, you know, also having more than two chromosome set. Now this is referring to the entire set of chromosomes. So they have 40 chromosomes, all 40 of them get an extra copy. And so we divide polyp Floyd's into two classes, which we'll go over individually. But the first classes, auto polyp Lloyd's and this is multiple chromosome set from one species. And this is kind of the most intuitive one. Right? We just think of everything, something happening with replication and therefore you get this extra chromosome. But of course it's from the same species. So this is the most intuitive, but there's actually this second class called all a polyp voids and they contain multiple chromosome set from two different but closely related species. And you're like, oh my gosh, how does this happen? Does this happen in animals? And can But mostly this occurs in plants. Um so this is a very common or not very common, but it does exist in plants and these chromosome set. We normally call them homologous chromosomes, right? If they're from the same species, but because they're not from the same species and they are different. We give them a special name and this name is home analogous. So it's semi homologous. So I realized that the spelling between these two are very similar but it's this you know extra E here that makes them different. So the home ya'll agus is sort of similar. They're similar steps and a homologous are from the same species. Like I said a ton of vocab. So here's the difference. So here we have the auto polyp Floyd's. These are with chromosomes from the same species. So say they're supposed to have two chromosomes. It's supposed to be deployed but they end up with three. But you can see that all the colors are the same, right? It's black, blue and red. It's all the same color. So they're from the same species. Same species. Whereas this one you can see that they're similar. It's also supposed to be deployed. So you have this third copy here and you can see that it's really similar, right? Like gray and black. Not that different. Light blue, dark blue, pink, red. Really not that different. They're fairly similar but they actually are from different species. So that is the difference between a low and auto polyp Lloyd's. So we're gonna talk about age, individual one and more death. But let's move on

Okay so now let's talk more specifically about auto polyp Lloyd. So auto polyp Floyd er Typically trip Lloyd's not all the time but most of the time they're Trip Lloyd's usually auto polyp Lloyd individuals are sterile and this is because their gametes will receive either two or one chromosome from each pair. So let's say here that they have these different colors here. So they are typically trip Lloyd Wright. So they have one chromosome here. Tripp Loyd one here, that's Tripp Loyd and one here that's Tripp Loyd. Now when this undergoes mitosis to create these gametes, what happens is that some of the daughter cells will actually end up with two copies and others of the daughter cells will end up with one copy. Right? Because they started out with three. Now it's very unlikely that only one cell will get all all too. Usually what will happen is that it will get one here and chew here and maybe two here and one here. And so you end up with this mix where some of the chromosomes have two copies and some of them have one and this creates a gammy that is just not viable. So when it undergoes fertilization with a normal gamut sometimes it's gonna have some Tripp Loyd it's gonna have some that end up is deployed and it's just going to be very confusing. Right? And so the gamut typically doesn't survive. So typically auto pato ploys are sterile and so what it's called whenever there are mixed numbers of chromosome sets. So some chromosomes have two copies. Some have one. Some have three. This is given a special term called an employee. And we're gonna be talking about this a lot. Remember you go back to the previous video. This was one of the different types of chromosome mutations that when we're not talking about yet. But this is when you have a mixture of deployed and hap Lloyd chromosomes that can even be trip Lloyd wright. Any kind of unusual mixture of a chromosome set. Because not all of these trip lloyds here will just segregate equally. Right. There's three of them. So sometimes too will go to one and sometimes one will go to that one. Now there are many classes of auto polyp lloyds. You have mono ploy AIDS. This is using a half Lloyd sale meant for fertilization as an embryo. We talked about this before with the bees and the wasps. This was that parthenogenesis term that I used before. So these are mono ploy kids. This is the organism that develops from that parthenogenesis, you can have auto trip Lloyd's. Um these are tripp Loyd for each set. An example of this is bananas. So it has the entire if it has 40 chromosomes, all 40 of them have three copies and you can also have auto text Floyd's which um again our foreign for Tetra for in here and we can see this sometimes in plants such as crops or even like large flowers because typically this results in a larger size. And you often see that in auto polyp loyalty because you have the entire chromosome set having multiple copies. And so in the organisms that can survive with that which is kind of rare. But in the organisms that can typically they're just bigger, right? They have extra chromosomes, they're producing extra of every gene that they have. And if they can survive doing that with some plants, can some amphibians can they're typically just bigger organisms. Very common. So here we go. So here's some example. You have a mono ploy. This is where that one chromosome is used as an embryo without fertilization. Here's an auto trip Lloyd where you have three copies of every set, which we've seen this before. Um But essentially that's the example. So this is this is auto polyp Lloyd. So with that let's turn the page.

Okay, So now let's talk about a low poly Floyd. So all a polyp Floyd's typically is a plant plants that is a hybrid of two or more species. Usually these are sterile again. Um and most of these are synthetically created for crops. So, example of these types are cotton and wheat. So what does this look like? So here are our original organisms right here. They have one copy or they have two copies of each of their chromosomes set. But what happens is that somehow, usually through some kind of genetic manipulation, um, these are fused together. And what you get is you get combinations, you get the red chromosomes here and the black chromosomes here. So now you have all polyp Lloyd's, right? Because they have chromosome sets from different organisms. It could also be um where if you got an extra chromosome here and an extra chromosome here, but they came from different regions. So this red chromosome would come from this organism and this black chromosome would come from this organism. It's a little different than how I've drawn it. But you have two choices here, right? You can get a mixture of these two chromosome sets or you can get what I showed before in that first video of extra chromosomes from that individual. So this would be if we're doing it here. Here's the blue chromosome obviously that's going to fuse this way. But you could get a light blue chromosome for instance, from this organism. That's not perfectly the same, but close enough. Um, and it would come over here and the same for here. You could get the black chromosomes going here and creating this big fusion organism. Or you could get a sort of gray chromosome coming from this blue cell to be here. Either one it's all a polyp or pretty much all. Apollo just means some kind of mixture of two chromosome two chromosomes set from different species. So it can be, they're fusing together those two chromosomes. It can be donating a set of chromosomes from one individual to another. But essentially this is an example of a low poly. So here's another one with the red and the blue. Now here's some terms that I wanted to make sure that I got in um they don't necessarily go with all polly party, they could go anywhere, but they're so little. I figured I just saw him in here at the end versus indo polyp Lloyd. E these are deployed organisms but certain cells or polyp Lloyd. So this is actually um can describe some humans. There are liver sale cells in humans that actually have different amounts of chromosome numbers or can have different amounts of chromosome numbers. And so we can call those people in bhopal if Floyd. This also happens in gut of mosquito larva where the majority of the mosquito has one set of chromosomes. But in this gut of the larva, some of the cells have extra chromosomes and also flowering plants. But essentially this is where the majority of the organism is deployed but then a few cells r. Tripp Loyd and then finally there's this chemical you may see in your book, I don't know how to pronounce it. Colleague King king. Anyways, this big C word here and this is a chemical that you can put on sales in a laboratory setting um to induce non disjunction. Now, I don't know if you've heard of this word. You may have or may haven't um depending on what order you're kind of watching these videos in. But um non disjunction just means that the chromosomes failed to separate properly during diagnosis. So if you have a cell here with two chromosomes, non disjunction would be if in the daughter cells if two of them went here and none of them went here, that would be non disjunction. It could also be if you have a trip Lloyd organism. Right? And in the daughter cells you have two. So three go here or to go here and one goes here. Either way, they're not separating equally. So that is non disjunction. So this chemical can actually induce that in a laboratory setting. In case you ever need to like study any of these processes. So with that let's now move on