Bye bye. Oh, can't he? What? Oh Yeah, I can he now heard you now. How old are you? I'm good. Yeah. Okay. So I just need to do catture. Obviously you haven't had a lesson in a while. And how's things going in biology at school is difficult. Is difficult. So what's been happening? Because, I mean, the last time we had a lesson was about a month ago now. And even after that, I think, I think it was only one lesson after the summer. So what's been going on in biology at school? Have you had any recent assessments or anything? Yeah, I have, but I love doing the school. You left them at school. Do you remember what topics they were on? Yeah. What topic are you currently studying? Wow, the tree. I need to try and use the ground handle. Can you have a look? Do you have your book with you? Like your book or your father der from school? The teacher, take away my book. What about your textbook? Do you have like a revision guide that you use at home? Next book? No, I mean, we teach take away all books. So how do you revise after school? Like how do you revise outside of school? Outside school? Yes. Like you learn in school Yeah your topics but you need to go over them and revise them outside of school. So how do you do that if you don't have your book or your have Yeah we have book but because we have a holiday you know have to before the holiday the teacher will be take away this book Oh so you usually have the book but you don't this week Yeah Yeah I have book Yeah but not this week. Okay, okay, that's fine. Okay. So if I remember rightly, the last time we had lessons, we were moving on to the nervous system. We were looking at unit five, which was homeostasis and in the nervous system, have you been doing that recently in school? Do you know like the nervous system? Hormones, perhaps reflexes? No, really, I can't remember it. Can you try and have think what you've been studying in biology recently, just so I can help you continue that? I think the most recent thing you did before you went on the holidays in biology, were you doing about photosynthesis and respiration? No, we're doing about inheritance. So parents t dna things like that. Yeah Yeah Yeah you've been doing that. Yeah. Okay, so you must be on topic six then. Okay, which is inheritance and ecology. So we'll go on from there. Sorry, not have inheritance. Inheritance is six. Ecology is seven. So we'll start there. We'll have a look at what you know. Do you have mock exams coming up in December and January or December or January? Yeah do you know when December or January. No sure because they not tell me at clearly ly time. Okay, so it could be before Christmas or after Christmas you're not sure I have lot of Oh, it's before the Christmas I have one. After Christmas I have another one. Oh, you're splitting it. It's quite unusual. And the last the last test is in the next year. Yeah actually Yeah the Yeah Yeah Yeah no, I know I know your real ones will be in the summer, but I'm talking about the mock exams so like the practice ones. Yeah is that before the Christmas? Before Christmas? Yeah. Okay, that's to be expected. And just one last question. When we had our lessons, obviously before summer and over summer, you weren't sure whether you're doing higher paper or foundation paper. Do you know yet? Yeah, maybe. Which one higher author foundation foundation as and so I'm not here. Okay, that's fine. Right. I'm just adding that to my notes. That's all because it helps me to move all of those things around the head. Ds, are different. Say that again, the foundation on the hair is a different. Yes, different. So one of them more difficult. The higher paper. Pers, more difficult. And there's more content on it only like maybe it's some of the topics are on there. Most of the topics are the same. But then some there's some added topics for the higher paper that you wouldn't do for foundation that's all right. Let's have a talk through then dna and inheritance. Okay, so I'm just gonna get some the only reason I'm not using my iPad is because classing usually crashes when I use my I had it at the same time as my laptop for some reason. And did you find out? Are you doing combined or triple by the way? You know like are you doing three separate sciences or are you doing the combined course? So there's two options when doing biology or science in general. You either do three different sciences, like three different gccs, or you still do three sciences, but you get two gcat the end of it. And we call that the combined Science Award. It's like one of them is called trilogy. I'm not really sure, but I remember it's three different. No, no, it's too. It's too you're doing too. So what we think you're doing then is combined Science Foundation paper, right? That's where we think we are. Yeah, Yeah, Yeah. Okay, okay, that's fine. That makes sense to me. Okay, so first of all, let's talk about reproduction as the first part of unit six. Okay? Now reproduction in biology is the making or the process of making new cells or organisms, okay? So reproduction is a critical process that happens in all living organisms, whether they're made up of one cell or many cells. Okay, there are a few different types of cell reproduction. There are three types of cell reproduction and I'm gonna to write them on here and I want you to try and tell to me if you recognize any of them. So we've got matosis, we've got meiosis and we've got binary fiokay. So there's the three different types of methods that we could come across at gcse of cells dividing. Now, do you think you could tell me what any of those means? Do you recognize any of those terms? Do you know what any of them mean? Oh, really? Sure. No. Okay. Do you recognize any of them? Yeah like do you recognize the word do do you like recognize the the words mitosis, meiosis and binary fision? Hold on, I can't hear three on the screen. We recognize any of them. These three words, the cities. Yeah. Do you recommend anything? Do you feel what they need? Yeah, I know. Can you tell me any of them? I. The I know the binary. It's been the second time to I don't know how to see. You can type it if you want. If you might find it easier, you can type it beneath the word binary rather than trying to articulate it. Afka hudo explains this word. That's fine. So the three methods, these are all types of cell division, but they are involved in different circumstances. Now I'll talk about mitosis. First of all, my tosis is a type of cell division. It occurs in eukaryotic cells only. Okay, so eukaryotic cells only produces two genetically identical. Daughter cells. Okay, so it is a type of cell division first sible. It happens in you cararyotic cells only. And it produced this two genetically identical daughter cells. So this is what would happen with mitosis. You start off, you've got your parents. So I'm going to add in a little bit of detail to this cell. And when that cell copies itself, it produces two exact copies. So this is a bit like cloning, to be honest. So it is very similar to cloning. The cells produced are exactly the same as the parent. Now, what do you even forgot? The word eucharyotic cell. If a cell is eukaryotic, that word in the second I put, what does it mean? Eukaryotic cell? You exiyeah you kareu karyotic. Yeah this work let me highlight. So I think you know this one because I definitely talked about it with you. You Carry off this. What does that word mean when we're talking about cells? Near. Say that again. Oh, I forgot. Okay, there are two types of self in biodelogy. One is you Carry out it and the other is karyotic. So you karyotic cells are you karyotic cells? I'll put this in. You karyotic cells are cells that contain a nucleus for one and other membrane bound organelles or membrane bound structures. Eukaryotic cells include animal plants and fungal cells. So really the most important distinction is eukaryotic cells have any nucleus, okay? It doesn't have a nucleus. It's a prokaryotic cell. If it does have a nucleit's, a eukaryotic cell. Now which type of cell have I missed out there? So if we look at animal, plant and fungal cells, is there one more? Whether there it is, what is the other type of cell that we study at gcfc biology that's not included in that list? Because it has a nucleus or it doesn't have a nucleus in this case. What is the one type of cell that you know that does not have a nucleus? No. I know if I give you a clue, so these types of cells can sometimes cause illness, so if you catch them, maybe can sometimes make you ill. Yeah. You can't see them. You can't see any type of cell, but you can't see these. I don't see. I'm going to start drawing one for you, and you can tell me if you have any idea what this might be. And remember, this is going to be a prkaryotic cell. So it's not the same as an animal cell or plcell. This is a plant cell. This no, this is not a conct or an animal ual cell. It's a different type of cell on. It's a prkaryotic cell. But I want you to tell me what it is. It's a tiny little microcororganism. These can sometimes cause disease. They can go on. I need you. What were you going to say then? What did you think? Remember, it doesn't have a nuclear. It's not animal, plant or fungus. It's another one beginning with b. I'll give you a clue. It's a type of cell that begins with b. What about if I give you those three? Yes, bacterial cells done. So binary fission occurs in bacterial cells only and does also produce two genetically identical cells. Okay? So mitosis and binary fission are quite similar. The only difference it is that binary refission happens in bacteria, whereas mitosis happens in animal cells, plants cells, and fungal cells. So essentially use karyotic cells. Okay? So they're quite similar processes in that they produce two copies of the cell. I am going to put those there so that they don't get in their way. So that's one copy and this would be a second copy. So that's binary efficient. Now meiosis is different from those two, and it's really what makes the basis of sexual reproduction for this topic. So when this topic, when we're talking about new dna and characteristics being inherited by children from their parents, meiosis is the reason why. Now the second thing is, I'm sorry, the definition I'm going to put here is it is as well a type of cell division. It occurs in eukaryotic cells only. And it produces four cells that are not genetically identical. And each cell is haploid, which means it has 50% of the normal dna. Okay? So each cell is haploid, it has 50% of the normal dna. So this is what happens in animals, and they Carry out myosis. So first of all, they have a first round of division where they produce cells that are quite similar. And then they have another round of division where they produce another load of cells. This time those cells are smaller, and they are not exactly the same. They have different dna to each other. Now, in humans or in animals and in plants, I suppose we call these cells gametes, okay? And they're going to be really important for the study of reproduction gametes. So look at mitosis on the left. Look at binary fission on the right. Both of those have one round of division where they produce two new cells. Meiosis in the middle is the one that's the most different, because there is two rounds of division and there are four cells that are produced in the end, and they are haploid, which means that they have 50% of the normal dna. Now I'm gonna to put this word here. These are gametes. Okay, gametes, you'll recognize that term. What are the gametes in humans, do you think? What do we call them? What are the two cells be? Humans that only have half dna. Yeah, what other human reproductive cells? Let me write this out here. So what are the human reproductive cells? They care the gametes. Cold. What's the name? There's two versions. I'm going to start drawing them so that you have a little bit of a clue. There are two types. These are cells, remember, in the human body. I know you know this one also. It's a. Spam and over Yeah sperm in an egg cell. Well done. Over. I think you're thinking of planets, but this is a sperm cell and an egg cell. Excellent. So they are our gametes in humans. They are different from every other cell in the human body because they only have 50% dna. So this is a sperm cell. This would only be found in male humans. And that's the same for any animal as well. And this is an egg cell, and that would only be found in females animals, and they only have 50% genetic information. So both the sperm and egg cells are different from most other body cells as each shop them only has 50% of the normal dna. How much is how much dna is normal in humans? Justin, what is the normal amount of chromosomes in human cells? So. How many chromosomes are in each of your cells, each of your body cells? It's a number that you Yeah, I'm mine, same as me. You and me have the same number of chromosomes in ourselves cells because we're humans. The number of chromosomes in the cells of humans is the same in every single human. Don't know. 46. Does that number sound familiar? 46. Yeah. So in every single cell we have 46 chromosomes. Okay. So you're made up of trillions of cells. 37 trillion, I think, was the number as an adult. And in each of those cells is 46 chromosomes. However, let's put this, however, gametes. So sperm and egg cells only have. 50% dna, so they only have 23 chromosomes each. Okay? So normal body cells are supposed to have 46 chromosomes. However, sperm and egg cells only have 23 each. Now the reason for that is because they will join together, okay? So to make a new life, a sperm cell and an egl join ined together. So the egl has 23, okay? And the sperm cell also has 23. So I'm just going to put the little numbers in there. There we go. So the sperm cell has 23. The egg cell has 23. So when they join together, what's the total? If you add those two together, what do you get? So when the sperm cell 23 and the egg cell 23 chromosomes, well, when they feed together the chromosomes, join ined together the chromosomes Yeah I'll join our chat. So there is a total of so if the sperm cell had 23 and the egg cell had 23, how many do they have together? How many do they have in total? Exactly? There is a total of 46 chromosomes. And so a new life can be formed from that, okay? So you end up with a new cell that is bigger and now has 46 chromosomes, and this one is going to start forming new life, okay? So that is the basis of fertilization, really. We call this process here fertilization, which means the sperm and the egg cells join together, and that's when they share their dna, okay? Fertilization, which is the joining of an egel and a sperm cell. Now this type of reproduction is called sexual reproduction, and happens in animals and some plants, okay? So this happens in animals and some plants. So sexual reproduction, that is where there are two parents, okay? There are two parent cells that join together and the dna is shared, okay? So sexual reproduction involves two parent cells. And the new organism, which we call the offspring. Has a combination of parents dna, so that's why each person who lives on planet earth right now, each person has two parents, a mother and a father, right? Every single human being has a mother and a father, or at least did at some point, because that's how new life is formed in humans, which means that every single human being is a mixture of their mother and their father. They have a 50% mix. Now. Why do you think that that might be a good thing? Jon, why do you think that having a mix of dna might be a good thing? Why might that be a benefit? Hmm. No, that okay, let me tell you something and then see if you can Carry on from what I'm saying. So sexual reproduction produces offspring with new combinations of dna. So what I'm saying here is each individual is unique. They are not an exact copy of either of their parents. So like me, for example, I obviously have a mother and a father and I am not a copy of either one of them. I'm not their clone, I'm not my mother's clone, nor am I my father's clone. I am a new person, but I have a mixture of their dna. So 50% of my dna is my father's and 50% of my dna. The rest, the other 50%, is my mother's, right? So I'm a completely new person. There is nobody else who has the same dna as me, just as there is nobody else who has the same dna as you. Now this allows for variation, okay? So what that means is we are all different, okay? You're different to me. You're different to do you have any siblings, any brothers or sisters? No, no. So it's just you. Yeah. Okay. Well, you're different to your parents. Do you have any cousins or anything like that? No, no. Okay. So you're different to all of your friends though you have friends, I assume you're different to all of your friends. You're different to all of your school. Those you do have, you're different to people that you know at school. So your peers, you're different to your teachers, you're different to your tutors, you're different to people that you PaaS on the street. So why do you think it's good for us as humans to all be different? I could rephrase that and say, why do you think it would be a bad thing if we were all the same? Why would it be a bad thing if we were all exactly the same as each other? That's question. Okay, please, why would it be a bad thing if all humans were exactly the same? So imagine we were all clones. Okay? Imagine there was, imagine you cloned yourself and there was 7 billion of you on planet earth, just 7 billion versions of you. Why would that be a bad thing? Let let me sort of continue with this, right? What are some things that you're really is the you don't think this is what sorry, I don't think this is sping basing. What do you mean by. When you write what you're saying, I don't understand the word you're saying there. Let's says this is good nor bad. Oh, Oh, right. You don't think it's a bad thing. I see, I see. I get what you mean, right? Let me ask you something then. What are you good at? What skills do you have? What skills do you have? Like what is something you're really good at? Everything. Well, what what save you to pick one thing. Okay, music, music, music. Okay. So you're really talented at music. Great. What's something that you would say you're not so good at? Like what would something you say that you don't like or you find boring or you're not the best at? No idea. Do you like really like, you don't have anything you don't like? Do you like them? Let me think of something. Do you like gardening? Have you ever been gardening before looking after plants? What was it does? You know, when you go outside, and you know when you plant things outside, people who look after grass. So it's a gardening. Gardening, yes. So people who like grow trees and grow plants and make outside of this, Oh, I love this before my child. So are you good? Are you good at gardening? No good. But I think, okay. So here's my issue, right? If you're really good at music but you're not good at gardening, now we need somebody on planet earth who's good at gardening. We need somebody to look after the plants, right? We need somebody there to do that. Now if there was only 7 billion versions of you, wehave 7 billion people who were really good at music, not very good at gardening, okay? So that's the issue. When we have lots of different people and there's variation, we all are able to excel and participate in different things. So you might go on to be a famous musician, okay, great. I'm never gonna to do that because I can't play any music. I'm terrible of music actually. I can't play an instrument. So but that's fine because I do my thing and you do yours. You're going to go on and do that. And then somebody else in your class might go on and be a builder. Somebody else might become a doctor, somebody else might become a lawyer, somebody else might become a pilot. The thing is, we are all different. So we all have different skills and we all contribute different things. Now that is on a human level, on a genetic level, all of us having different dna means that we can adapt and also we can resist change as well. So if all of us had the exact same dna, we would be killed by one disease one day, okay? We would all be wiped out by one disease if we had the same dna. But because we don't, we don't. There are people that have asthma, there are people that have cancer, there are people that have all sorts of genetic diseases, but not all of us because we're all different, okay? And that's a good thing. Variation is very, very, very important in a population. Okay, now I'm going to write a little sentence here. So variation is important in large populations. In large populations as it means that everybody is different and contributes. Different things, different skills to society. On a genetic level, variation allows a species to adapt. And resist disease. So let me ask you a question. Have you heard of this term here, natural selection or survival of the fittest? So what I'm writing here, natural selection or survival of the fittest, do you recognize either of those two terms? Survival of the fittest, you might recognize more. Thank you legs. You've seen of either of those before survival of the fittest. That mean no, you haven't noticthat's. Okay, let me try and give you an example here. I'm going to try and use a human example. I'm going to try and okay, let me give you an example. Many years ago, and I'm talking millions of years, okay, giraffes used to have quite short necks. Now excuse my terrible drawing because I am not good at art. Again, this is one of my many things that I'm not good at. So here is a giraffe. Okay? So here is a giraffe. Millions of years ago. It has a pretty short neck compared to giraffes that we recognize these days. Okay, so this is a giraffe. This is from millions of years ago. So millions of years ago, all giraffes had short necks like this. They looked like more like horses, okay? So they used to eat food from trees and bushes. So like here. So the trees used to be about this big and the giraffes would be able to eat food from them. Now, every now and then there was a giraffe born that had a longer neck than the rest. Okay, so I'm going to make one of these giraffes have a longer neck. All right, so this is a long neck giraffe. Now he is unusual in his population because most of them have short necks. Actually I'm just gonna na get rid of these ones down here so I can show the difference between the trees. So here in this population there are three giraffes. I am going to add another one, and one of them has a long neck. Why? Because he is a anomaly. For some reason, he's been born with a, with a long neck. Do you know, do you remember what we call it, Justin, when the dna changes and leads to a new characteristic, or something changing about the individual. No mutation. Do you remember that term now? Mutation? Yeah. Does it sound familiar? No. Okay. So a mutation is another important word in this topic. A mutation is a change in the sequence of dna that sometimes leads to a new characteristic. Okay? What that means is in the individual, they should have been born with a short neck. Okay? They should have had a short neck, but something went wrong with the dna and there was a mistake in the dna. But that led to the giraffe being born with a long neck. Okay, so that's the giraffe there, the one in the middle to the right, he has a long neck, whilst all of the others have short necks, right? So why do you think the long neck might help him to survive? Why might he survive along within the other giraffes if he's got a long neck? Yeah, so this one here, this giraffe, why might he survive longer if he's got a longer neck? See how his neck is longer? He's taller. Why might he survive longer? Because da is different. Say that again. Da is different. Yeah, his dna is different. Yeah, well done. He has had a mutation happen to him potentially, but why might he survive longer? I'm going to write this in here. So the third juror has a longer neck than all of the others due to mutation. Why might the long neck allow him to survive for longer than the other giraffes? So why might he live longer? He's longer. Yeah. Why might he live longer? Really? Think about this one. Why might he live longer than the other giraffes just because he has a longer neck? So he doesn't die as quickly. He doesn't die. He Yeah, he's older. Yeah, he lives. He lives to an older age. He lives for longer. He survives for longer. Why though? Why might his neck have something to do with this? Yeah, he's taller. He's definitely tall up. I don't know. Okay, if he's taller, he can eat food from bigger trees, okay? So he can reach, he can reach trees that are higher. Yeah, you get it. He reaches trees that are higher up. So he's not competing with the other giraffes. So basically, if he's taller, if his neck is longer, he can reach food that is higher up in the trees, whereas the other giraffes, they're too small, they're too short, okay? So they're all competing with each other. So all three of these giraffes, they're all eating the same food. They're eating the food from the same trees because they're all the same height. The taller giraffe, he stands above them and he eats food from above them. So he doesn't compete with any of those. There is no competition. What that means is he has more food, he can survive longer. He's not going to starve to death like the other ones, and therefore he is more likely to survive. This is what we call survival of the fittest. Okay? This is what we call survival of the fittest. So this is what we look at in terms of a little bit further in the dna topic. So number one, the taller Jura can eat food or leaves that are higher up in the trees, but the smaller giraffes cannot, not because they can't reach it, okay? The smaller drarats can as they can't reach. This means that all of the small giraffes are competing with each other. Therefore, there is less food for the shorter giraffes. There is less food available for the short ones, more available for the tall jua. Therefore, he survives for longer because he does not starve today. He survives longer as he does not starve now. Him having different dna was helpful there. Yeah, it allowed him to be well, it allowed him to be better than the other giraffes at getting food. So this is what we call survival of the fittest. This is natural selection. It's evolution, or it's the basis of evolution. So because he's taller, because he's different to the other giraffes, he is more successful. He's more likely to survive. Now, this was millions of years ago. Okay? Now all giraffes have long necks. And the reason is because that one giraffes, he reproduced, and he reproduced again, then his children reproduced and they reproduced. And over a long time, all of the giraffes had long necks. Okay? And that's what we call evolution. Yeah that's the basis of evolution. So to go back to the point, natural selection, survival of the fittest, genetic diversity, all of this is because of sexual reproduction. Sexual reproduction is the only type of reproduction that produces variation. Now remember, variation is really, really, really important. The it means that we're all different and that is a good thing because we are able to adapt and we don't all die from the same diseases, okay? We are not all wiped out by a disease. However, there are some downsides to sexual reproduction, okay? So sexual reproduction is good because it produces genetic variation. So let me just put this in here. So sexual reproduction. So we have grows. It causes genetic variation. So it causes genetic variation, which allows for adaptation and resilience, which means we don't get diseases. Pons, okay? So there are some pons to genetic variation. It is more time consuming, okay? So think about animals, humans included. It takes a while, right, to find a partner, to find a match. This is humans and other animals as well. It's more time consuming then it takes a long time to grow new life. For humans, it's like nine months, 40 weeks. For some mammals, it's longer. For others it's shorter, but it is time consuming. And secondly, it requires more energy. Okay, so more energy is required for sexual reproduction than for just cloning. If your cells just copy each other, really quick, really simple, not a lot of energy required. But for two cells to fuse together, dna to mix together, and then to form a new life that requires a lot of energy, it does not guarantee that a desired characteristic will be passed on. Okay, so example, let's have a mother who is, let's say we've got a mother who's got Brown eyes. Now, let's say she's got blue eyes. Okay, let's say she's got blue eyes. Let's say the father also has blue eyes. No, this is a bad example actually, because we can't do that, let's say. Let's say Brown eyes. Okay, so let's say Brown eyes and let's say the father has blue eyes. So the mother and the father, they have a baby. They want the baby to have blue eyes, okay? They want a blue eyed baby, let's say. So this is the mother and this is the father. Mother has Brown eyes and father has blue eyes. They have a baby and the baby has Brown eyes. Okay? The baby's born with Brown eyes. They wanted the baby to be born with blue eyes. But that's not how genetics works. Okay? So in their case, the desired characteristic was blue eyes, but why is this baby not guaranteed to get blue eyes? Why did it not get blue eyes even though the father had blue eyes? Why does the baby not have blue eyes? What could be a reason? Have a look at the mother. Oh, because he mother is groright. Yeah. So the baby has gained the characteristic from the mother. It does also get an alol from the father, but we'll get to that in a bit. So with genetics, because we're mixing the dna, you can't be sure which characteristics an individual is going to get. So sometimes the mother has certain characteristics that are desirable. Maybe she has Brown eyes, maybe she has long hair, maybe she has great skin, whatever the whatever the characteristics. But that does not mean that the baby or the child will have those characteristics. Because genetics are complicated, they are not guaranteed. It's completely random. Okay? So if a parent has a characteristic, a good characteristic, that does not mean that the child will have that characteristic. Think about it. Are there any things that you've inherited from your parents that you're happy about? Is there anything that you know about yourself, like the way you look, cause talents that you have or anything? Is there anything that you've inherited from your parents that you're happy about that you're glad you've got that characteristic? Is there anything that your parents have that you have that's that you can see similarities between you and either one of your parents? I don't know. No. Okay. So for example, no, that's why only if you can't. So sometimes, like sometimes parents will have really good characteristics, like good genes and and children are happy to inherit them. And other times parents have maybe things that you wouldn't want to inherit and the child is glad that they don't. But my point is that genetics are very complex, okay? There is never a guaranteed outcome. You you can not look at two people and tell them what their child will look like. It is so random and there are so many different combinations of dna. So dna is very, very complex, which is most of the time a good thing. But also it means that if there is a characteristic that somebody has that they want to PaaS on, there's no guarantee. Like we can't say for sure that it's gonna to PaaS on. Okay, we don't know. So with sexual reproduction, there are good things and bad things. That is your pros and your cons. Okay, so genetic variation is the pro. It means that you get lots of new dna. It means that we can adapt. It means that evolution can take place. It means that we will not all die from a singular disease. But the cons or the disadvantages are that it is more time consuming, it requires more energy, and it does not guarantee that a desired characteristic will be passed on. Okay, so this is sexual reproduction. Going back up to the types of cell division. Meiosis is the type of cell division that's involved in sexual reproduction, because meiosis produces sperm cells and egg cells or pollen and ovle if you're looking at plants. Okay, so meiosis is the type of cell division that's involved in sexual reproduction. Mitosis is the cloning one. This is a type of asexual cell division. Do you know why your cells would do mitosis? Why do your cells divide in your body usually? What is it that our cells are trying to do? Why do we need to make more cells? When the time is gone, some celwill be die. So then the more, well done. Yeah. So growth and repair, excellent. So if we lose some cells, or if some die, they become non functional. We have to replace those with the same type of cell. So mitosis is a type of cell division that is not involved in reproduction, not in human reproduction anyway. We can we can say it's a type of reproduction because it's a type of cell reproduction, but it's not a type of organism reproduction. Okay? So mitosis, yes, absolutely. It's used for growth and repair. So when you get bigger, like as you're growing, you are adding more and more cells to your body, right? And that's because of mitosis if you break your skin, so if you damage your skin, the skin will repair itself because it's produced more cells by mitosis. Now that is a type of asexual reproduction. Now, asexual just means the opposite of sexual reproduction. So this is asexual reproduction, or it is a type of asexual reproduction. It is actually one word asexual like that. So is binary fission. Okay? Asexual reproduction, both of these are essentially just cloning. They are cloning their dna, and they are producing identical copies of themselves to replace old ones or to reproduce. Okay, so asexual versus sexual. Now if I was to scroll down and look at the sexual reproduction information, again, asexual reproduction is just the opposite, all right? So with asexual reproduction, there is no variation, none at all, because it's cloning. So remember, we were saying what it would be like to have 7 billion versions of U on planet earth. That would be asexual reproduction, because it's cloning. So you're producing genetically identical copies. So that's a bad thing, okay? Because we don't have any variation, which means there's no evolution, there's no adaptation, there's no survival of the fittest, there's no natural selection. And we are very, very. Not the immune. What's the word? We are very, very vulnerable because it means that a disease could come and wipe every single individual out. But the prose would be that it's quicker. It does not require that much energy. And if you clone yourself, you know that your desired characteristic will be passed on because you're a clone, right? There's no other input. So the pros and the cons of sexual reproduction are just reversed for asexual reproduction. So the things that we say are good for sexual are bad for asexual. And the things that we say are bad for sexual are good for asexual. So we just cross those two over. We just switch them over. Okay. Okay. So if you're are you going back to school tomorrow? Sorry, not tomorrow, it's Saturday. Are you going back to school on Monday? Yeah. Okay. What I want you to do for me then, because we're going to have another lesson next Saturday please if you can bring your book back or if you can't can you take some pictures of it or take a picture of the last lesson it Yeah that you did in class and send it to me just so I have a really good idea of where you are and also could you try and find out what what you're gonna na be doing for your mock exams? Okay, so ask the teacher is it gonna na be paper one? Is it going to be topics one to five and when you find out can you let me know? Okay of course Yep I'll post some feedback after the lesson and I'll write it there to remind you but that would be really really helpful all so I will see you again next Saturday. Okay good luck with your first day back and I'll see you then okay. Okay okay, see you soon, bye bye. Okay, see you, bye bye bye.