Is them, so you've just been relaxing at home. Yeah. Have you got any other plans? No. Oh, well, it's nice to I play my badminton a lot. And where do you go to play that? I have no clulike random like a sports center Yeah but like it's just for badminton and who you play with. I'm like this coach. Oh, so you're having actual lessons? Yeah. Sounds good. Is that your favorite spot? Yeah. Fantastic. Can you move that light up a little bit? Lender, it's a bit bright. Can you see that light above you? Yeah, okay, that's better. Well, I've not had a great week or so. I've managed to catch the flu. So there's a bad flu going around in the uk at the moment. And my daughter had it a few weeks ago and I thought I'd escaped, but I've managed to catch it. So if you see me muting, it will be because I'm coughing or blowing my nose. Is there anything like that in China at the moment? Yeah. Like like in this place right now. So like it's like really cold. Everyone is kind of getting sick. Yeah. Well, it happens every winter. I've been pretty unlucky. I've been ill for the past four Christmases. So Yeah, but at least I can, I can taste. Yeah, it's just it always hits at this time of year. One year I completely lost my smell and taste because I got Covid. But at least I can taste this year. So I'll be able to taste my Christmas dinner. But I'm a lot better than I was anyway, so that's good. I'm on the men, so hope you don't catch anything lender. No one of my students is at boarding school in England, and he's gone home to Hong Kong and he's got the flu and he's given it to all of his family in Hong Kong. Why? So they're having a miserable Christmas. Well, thank you for your homework. I've seen that. We'll mark it at the end if we have time. If not, I'll mark it after the lesson. Let's get started on our next topic, which is plant nutrition. So this lesson is going to be about photosynthesis. So there's different ways of starting this topic. Sometimes you start directly with photosynthesis. Sometimes you start with structure of a leaf. But we're going to start with photosynthesis, and then we'll go on to structure of a leaf. And the rest of the details in other lessons. So is starting. She wants to read the slide, please. Learning objto understand the process of photosynthesis success criteria to identify the reactant and products involved in photosynthesis to describe the process of photosynthesis and plants to describe how each reactant product enters and exit the plot. Mate, you want to tell me what reactant and product mean? So. Reactant? Is like like like carbon dioxide and water like info too soon as is like it's like something that starts like a chemical reaction, okay? So the reactants are the things that react together in the chemical reaction. Yeah. And the project is like a substance that is like made after the chemical reaction. Good. So the thing that is produced, and obviously that's a chemistry difference. That's a chemistry definition, but we are looking at a chemical reaction here in this biology lesson. So it all links together. So starting with a knowledge check, things that you should have done in year seven, just check king that you can remember everything. So giving you the pen and gonna to ask you to label. Can you type, because otherwise it gets a bit messy. Yeah, better. Of course, this is something you would have done much earlier than year seven. This is primary structure of a plant. Okay. And then we're zooming in on the leaf and we're zooming in on part of the root. So you should have done this when you did specialized cells. In year seven, anything that you can't remember, no problem. I will just remind you. So just do as many things as you can remember. Oh, Oh, no. What happened? Oh no. Oh, it's back. Whatever you did, what did you do? Because I was trying to click on the root hair out and then it clicked to the next page. Oh, okay, good. You haven't lost it. And they are all correct to the one that I haven't yet. No, it is a specialized cell. Now, it is the diagram that you would use for a typical plant cell. But this is a specialized cell which is found in the top layer of a leaf. It is a halisade cell. Yeah. Hey, good. So that's just a reminder of all of the different terminologies that we're going to need when we're talking about this topic, and that's just going to go through the outers. And we have got three questions here. I'm going to give you a few minutes to have a think about your answers. You don't have to write anything unless you need to write yourself some notes. But if you can keep your answers in your head, then that's absolutely fine. So I want you to think about how do you explain why plants need food, how plants get their food, and what would a world without plants or trees be like and why? So give you a little bit thinking time. So I'll just give you three minutes thinking time, and then you can share your thoughts. All. So it's time for you to do a look at presentation, answering those three questions if you go. Plants need food or energy. For like reproduction stuff. Boit's going to need food for like when this like the sun is limited. Ged, and like it's mostly darkness. Can't get their food by making their own food through photo sytenesses. Over we'll have no oxygen with that plant and send like plant by like the producers, there won't be any food ins and like there's gonna be more carbon dioxide since like plants absorb them. But now there's no more and there's going to be less habitats for animals. Very good. Can you give me a little bit more detail about the how do plants get their food parts? You've mentioned oxygen, carbon dioxide. Can you give me a bit more detail here? You sun赖. And carbon dioxide and water, which react and produce gluand oxygen. And like the gcoses, like the food. And you said, why do plants need food? You said, for energy. So how does this glucose then become energy? You might not have done that yet, so don't worry if you haven't. You can just say, I'm not sure yet. I'm not sure yet. Okay, no problem. Great, good detail. I think we have got some sample answers here. So plants rely on food to provide the energy, yet you mentioned that they needed to survive just like humans. So it enables all of the living processes, all of those life processes, movement, growth, reproduction, etcec to take place in the plant. So plants are producers rather than consumers, so they can't eat. So that's where we get the word producer from. So they produce or make their own food through a chemical reaction called photosynthesis. And it makes glucose. You mentioned that glucose is a carbohydrate. You probably remember that from animal nutrition. This link between how glucose then becomes energy will be covered. Possibly a little bit in this topic for plants. And then think next term or the third term this year, you will cover it in respiration. So that will be done in another topic. So plants can convert glucose to another type of carbohydrate called starch. So let's have a think about this, because this can be one of the misconceptions in this topic. So we know that photosynthesis produces glucose, and then glucose becomes energy fire, a process called respiration that you'll look at in more detail. Sometimes the plant will produce more glucose than it can use, just like if we eat too much food, there will be more than we need in our body. Now, what do we do with the excess calories that we eat? What happens in our body? It breaks down in the stomach. Because of like the acids and like it get absorbed when it goes down to like the small intestine. Yeah. Now that's the waste, but I'm talking about if we eat too many cakes and too many pies, unfortunately they don't just go through us. All of the nutrients from those cakes and pies go into our body, and I'm talking about all of the fats that we absorb. So what happens to us? You get fat, we get fat, and that is our store. Now that is meant to happen because we need many, many years ago, in the distant past, our food source wouldn't have been consistent. So there would be times and webe able to eat a lot, and then we would store the excess calories as fat. And then that would see us through times when there wasn't very much food. But of course, now there's plenty of food, so we just stay fat. Plants don't store their excess as fat. They store their excess as starch. So the glucose molecule becomes a starch molecule, and the starch is stored in the plant. How is glucose different to starch on a molecular level? Can you remember from animal nutrition, what does the molecule look like? How is it different? So there's it like the like their structure is different. Yeah in what way? Like glucose is like moa and like starch is made of a lot of glucose. Yeah, you've got it. So glucose is a smaller molecule, which is great because that means it can easily PaaS into the blood. Starch is made of glucose units joined together in the longer chain molecule, which makes it insoluble. So it can be stored and it will stay in one place in the plant. And that's why staris so useful for that. So that's all you need to know. Just understand the link between photosynthesis produces glucose, and then the excess glucose is changed to starch so that it can be stored. And then when the plan is short on glucose, during a period of bad weather, during the winter, when we have much shorter days, it can start to break those starch molecules back into the glucose. A world without plants or trees, so humans and animals wouldn't survive because of the lack of oxygen in the air, which is vital. And obviously, plants give out oxygen and we need to breathe oxygen. And then you also talked about global warming, because, of course, we know that plants take in carbon dioxide. So they help to reduce global warming. They help to reduce the carbon dioxide in the air. Photosynthesis. So let's think about this term. Where does this come from? Photo meaning light, synthesis, meaning put together. So putting together new molecules using light. So to make or produce using light. Alright, let me just double check. Yeah, let's go on to our first worksheet. Right. I don't actually need you to cut and stick because thattake a little bit too long. So let's just show you the whole thing, and then you can just write it out so there's all the information you need. So next to this on the right, my right, I'm not sure if it's your right. Write the photosynthesis equation. Word equation first and then symbol equation underneath it. But say like on like the the blank side. Yeah, just the blank side. I'm not sure it's on the right for me, but I'm not sure whether we're mirred dor or not. Can you change your color? Yeah. This okay. Yeah, that's better. You're going to probably have to write that one because otherwise all of your numbers are going to just be confusing. And put your arrow in to your word equation. Okay, good. So where does the carbon dioxide come from? From there? And how does it get into the plant? Does it like. And. From like this don't matter. Yeah have you done adaptations of a leaf yet? Yeah you've done that at school like like the large surface. Yeah, you've looked at the structure, you've looked at a cross section of a leaf and labeled all the different parts. Yeah. Yeah, okay, good yeso. Carbon dioxide entering through the stomata. Yeah and what about the water? It. Absorbed from the root? And how does that then travel around in the plant? Does it? Like get so like. Like the aspaces. No, that's fine. You haven't done that bit yet. That's okay. So there are structures in the plant ants, which are like our veins in our body. And there's two different structures, one that carries water around and then a different one that will Carry the glucose around. And they called the xylem and the flowem. And we will cover that in another lesson. And then the glucose. So these are our products. Glucose, we've talked about that, that will then go to the cells. And via the process of respiration, energy will be released and then oxygen. What happens to that? What happens to the oxygen? Like leave the plant soon, just don't matter. Okay. Yeah. So that's a waste product of the reaction. Now on the second one, your symbol equation, I notice that you have written light above the arrow. You want to explain where you've done that? Like it is light to like. Like it provides energy, so like it gets to glucose and oxygen. Good. So light is important in the reaction, but it is not a reactant and it is not a product. So Oh. Oh, I lost you there a minute. Be back. Yep, be back. So it is important in the reaction, but just like enzymes don't take part in reactions, they just speed them up, lights the same, so it doesn't actually take part in the reaction. You will sometimes see chlorophyll written above or below the arrow as well, because chlorophyll has an important role in photosynthesis, but it doesn't actually take part in the reaction, right? And then these symbols here. So can you explain to me what do these mean? For example, what does this six here mean? Does that mean like. Like six of the carbon. Carbon. What dioxide? Carbon atoms. Yeah. So six atoms of carbon, twelve atoms of hydrogen, six atoms of oxygen, and together they make a molecule. And what is that molecule? Cose glucose. That's why I said to you, don't type it. Because if you start writing, do you want to turn your camera off, Linda, and losing your signal? So if you start writing big numbers into a symbol equation, they have got a very different meaning. So for example, if I put a big six here, that means six molecules of glucose. So if I put a two here, that would mean what. Well, the use of carbon dioxide, carbon dioxide, carbon dioxide molecule is made up of the atoms, carbon, one carbon atom for every two oxygen atoms. So remember the difference between your atoms. And your molecules. Now this equation isn't balanced, but we don't need to worry about that at the moment. And what I mean by balanced is when we have got a symbol equation like this, it's a little bit like a seesaw. Just like if you had an equal sign in maths, the number of atoms on the right must be equal to the number of atoms on the left, because energy cannot be created or destroyed. All right, let's go back to our PowerPoint. Let's Carry on. So nothing new here. We've covered all of this word equation. Yeah lights above the arrow. Sometimes you'll see chlorophyll as well reptance and products and symbol equation. They're looking a bit more at sunlight now. So sunlight isn't a reactant. As I said, it doesn't actually take part. It just gives the reaction energy. So in chemistry, have you done exothermic and endothermic reactions? So that again, Linda, you broke up. No. So one reaction, exothermic, gives out energy, the other, endothermic, it needs energy to get it started. So it's not going to happen unless you give it a kickstart. And photosynthesis is like this. So it needs some energy to break the bonds of the reaction, the reactants, and start that process happening. So energy is transferred via the sun and absorbed by chlorophyll. So I said that chlorophyll plays an important role. Chlorophyll is the Green pigment in the chloroplasts. The energy is transferred to the chemical energy store of the products made during photosynthesis. So can you read this part here? She from the sun is transferred radiation Yeah next one. It absorbed by chlorophyll was in the chlorophoof paliid south. Okay. So chlorophyll is the Green pigment in the chloroplast. So it's the chlorophyll that absorbs the energy. Now obviously this is a lot more complicated, but at this point you don't need to get into any more detail. Not until a levels. Water next, so water is absorbed via the roots. In the process called osmosis. So osmosis is where water moves from an area of high concentration to an area of low concentration. And then it moves up in tubes called the xylem. And we'll look at those. Yeah. So that's pronounced xylem, even though it's a an x. We'll look at that in more detail in other lessons. Gases in and out. So gases through diffusion in the stomata. Where would we find the stomata in this leaf? At the bottom Yeah on the underside of the leaf. Why is that? What? Why are they on the underside of the leaf? Like said like it can let the carbon dioxide get in, the oxygen get out. Yeah theydo that if they were on the top. And the water, if it rains, doesn't go through it, not quite. But don't worry, we will look at that when we go to adaptations of a leaf necessso. It's a little bit more to it than that. Okay, that's the stmata, right? I am going to get you to summarize that. Now I'll put some keywords. That I would like you to include. And I'm going to cut this out as well. Right. So at the bottom, I'm going to add some keywords that I would like you to include. They won't necessarily be in order. You don't need to use the exact word. For example, you could say diffusion instead of diffuses. Get started when you're ready, lenda. Oh, Yeah, I didn't put start show in this one here where we can see the glucose molecules joining up to make a long chain starch molecule. Can you use the word starch in that one, Linder? Yeah or stored for later a starch. Now you can also put in this one that some oxygen will be used for respiration. Obviously, that's going to completely depend on the conditions, time of day, etceter respiration without the s. And then just starch in that one there, please. Oh, you've done it. Yep. Fantastic detail, very good. Let me put that onto the chat. Brilliant. Now what we're going to do now is I'm going to talk to you about your homework task. Have you done the experiment where you test a leaf four starch? No, right. So we won't have time to complete this. We might be able to watch the video. If not, I can put the video on the chat for you and you can do that as part of your homework. So we have got now it says this is for gcse biology. It's the same thing, so don't worry about it. So this is an experiment where you test a leaf for starch. What chemical do you think you use or what indicator do you use to test for starch? Think about digestion in humans. Think about your food tests. What indicator do you use for starch in your food tests? Despite like the solution Yeah, that's the indicator. What's it called? And it starts off a kind of Brown color. I rememberthe name hyadine. Do you remember now hard? Yeah, Yeah. Do you remember what color it goes if there is starch present? Black, that's it. It goes a blue black kind of color. So this is the video. So I'm going to get you to watch this. I'm going to put it on the chat. And this is just somebody in the lab going through the different steps for testing a leaf for starso. Basically, the first thing you've got to do is you've got to get rid of that Green colthe chlorophyll because otherwise you won't be able to see if your iodine has changed color. So you get rid of the Green color and then you do your starch test, just the same as you would in your food tests. Now let me see whether this is on the PowerPoint. If it is, that would be easiest. Like that's that quiz. No. So I'm going to give you. Couple of worksheets. So I'm going to give you this one here. I'm going to cross out the risk assessment because I don't need you to do that. So I'm gonna to get you to label the equipment here and you'll get all of that from watching the video. And then I'm going to get you to do results and conclusion here. So basically, this is going to test two different leaves, one which has been kept in the dark and one which has been left in the light. Now which one do you think is going to contain starch and y. So dark. Or light. Which one do you think? Lot. So why not a leaf that has been or a plant that has been kept in the dark? Why is that not going to have any starch? Because in dithere's you can't do any person this is Yeah. So the starch will have been converted back to glucose to be used as energy in the plant so that the plant can live. Obviously, once all of the starch stores have been used up, then the plant is going to eventually die. Yeah. So in the dark, the plant t's going to use up its store of starch, but in the light, it doesn't need to because it can photosynthesize and it will continue building up starch stores. Yeah. So we would expect there to be starch present in the leaf that's kept in the light. So your iodine would turn bluey black, but your leaf kept in the dark for a period of time, obviously it's got to use up its stores. You should not get any blue, black color change. So I'll put all of the information that you need for that on the chat. I'll also put the page from the revision guide as well to help you out because I know we haven't spent that long on it and then watch that video. So I'll put all of that on for you. And then next lesson, we'll go on to structure of the leaf. Okay, Linda, I will see see you next lesson. Bye next. Bye bye.