Respiration in Plants Class 9 ICSE Biology | Selina Chapter 7| Aerobic vs.Anaerobic Respiration

0:00 Hello everybody I hope you all are doing good I am Deepika from Learn Hub a free learning platform where you can study Physics Chemistry Maths Biology and SST absolutely for free only @ learn.com so today we are going to start the next chapter of class nine and the chapter is super duper easy and the chapter judge respiration in plants so without wasting any time let's get started respiration respiration is a process through which energy is released in our body

0:46 so this is what we have studied till now so this is a process which we also need means animals also need it plants also need it and because of this process our body gets energy and we can do our day to day activities so if we talk about plants then where do we need energy in plants plants need energy for photosynthesis plants need energy to transport water and minerals and food there are many such processes which are going on inside the plant so in every process Plants need energy for this, so that energy comes from respiration. So what happens in this process is

1:31 that the glucose that was formed inside the plants was formed during the process of photosynthesis. So what will plants do with the glucose that was formed? Plants will absorb oxygen. So the same oxygen that they released when photosynthesis took place. So once we write down the reaction of photosynthesis, I think we should write down the reaction of photosynthesis. So it is when carbon dioxide and water combine with each other in the presence of sunlight and chlorophyll. So this leads to the formation of glucose plus oxygen is released. So

2:21 what are plants doing here? They are absorbing this oxygen from the atmosphere. So now when this oxygen acts on glucose, carbon dioxide will be released and at the same time a lot of energy will be released. Now these activities keep going on in plants and animals. So if we talk about plants, then generally the process of photosynthesis takes place during the day and that Plants use a very small amount of the oxygen that is released from photosynthesis to release energy for themselves, but what happens here is that at night time photosynthesis will not take place because there is no sunlight, so at that time plants

3:06 use a lot of oxygen to break this glucose inside them and to release a lot of energy. So this energy is stored in the form of ATP, which is also called the energy currency of the cell. So I hope the basic concept is clear now about respiration here, now like we write a reaction for photosynthesis, so writing the reaction or equation of respiration here is also equally important, so what you have to do is you have to reverse the reactants and products, so the

3:53 products of photosynthesis will now become the reactants of respiration and the reactants will become products, very simple, so here glucose C6 H12 O6 that is glucose will combine with oxygen and it will The released carbon dioxide is carbon dioxide plus water and a lot of energy is released in the form of ATP. Okay, so we have been talking about ATP for a long time. What is the full form of ATP? It is adenosine triphosphate. Correct, so remember adenosine

4:40 triphosphate. It is the energy currency of the cell. So this entire process of respiration is not completed in a single reaction. So there are multiple steps in which this breakdown takes place. So the first step in the process of respiration is the breakdown of glucose. So this breakdown takes place in multiple steps. The first step is glucose, sorry not glucose but glycolysis. So glycolysis glyco means glucose here, the glucose and lysine

5:25 that the plants made in photosynthesis. Now what will it do? It will start breaking down that glucose. So that step is called glycolysis. And this happens in the cell in the cytoplasm. And there is one very important thing for us to remember. That is this. Step does not require oxygen So this step does not require oxygen at all in this step. So this is that step. Yes, this is that step of the breakdown of glucose, which occurs in aerobic conditions as well as in anaerobic respiration. So this step, the

6:11 breakdown of glucose, is a common step in aerobic as well as in anaerobic respiration. Alright, aerobic and anaerobic, we know aerobic where oxygen is required to break down anything and there is no requirement of anaerobic oxygen, but this is a step which we will see in both. Then the next step, now what will happen here, when the glucose breaks, what will happen here, when the glucose breaks, the glucose will get converted into pyrovate. Alright, so what is glucose? It is a six carbon compound, so this is a C6 compound, when it breaks into pyrovate,

6:58 then pyrovate is a three carbon compound, so how many pyrovate will be formed from one glucose? Think, this is six, this is three, so this means Here two pyro fat molecules will be formed, it is clear, simple, after that the next step that comes is the Krabs cycle, which is also called the citric acid cycle, because in between this whole cycle has multiple steps, similarly when glucose is formed as pyro fat, then this whole step, this glycosylation, is a 10 step process, so here 10 different intermediates are formed or nine different intermediates are formed and then glucose is converted into pyro fat, so here the

7:44 next step that is the Krabs cycle, there are multiple steps in it too, multiple intermediates are formed, energy is released at some steps, but we will not study that today because that is not in our syllabus for class nine, okay, so we will just understand that when this glue pyro fat is formed, what will the pyro fat do now, if it is formed in the cytoplasm of the cell, then this pyro fat will enter into the mitochondrion and when it enters the mitochondrion, then Now carbon dioxide will also be formed here, water will also be formed here and a lot of energy will also be released here. So this means that the

8:33 glycolytic cycle is taking place inside the mitochondrion. Okay, what is the mitochondrion cell organ that we used to call the power house of the cell. Very good. So, this is the power house of the cell, that is why we call it because when the pyrovide goes inside the mitochondrion, now a lot of energy will be released here from this pyrovide. So that is why mitochondrion is called as the power house of the cell. So, I hope this is clear. Now this was the first characteristic or the first step of respiration. Now the second characteristic in this is enzymes. So, here suitable enzymes are also required so that this entire process of respiration

9:20 continues in very smooth steps. So, we need enzymes, particular or suitable enzymes. Now, after that, finally, energy is released here, that is ATP. So, what will happen here? Here, there is glucose from glucose. Carbon dioxide will be formed and water will be formed. So we know that this is not happening in one step here. There are many steps evolved here. So now energy will be formed here. Now some of the energy will be liberated in the form of heat, which means it will come out in the form of heat, but the rest of the energy will be converted into the form of ATP. Now when we need energy, when the plant needs energy, the plant will use this ATP to do its work.

10:07 But when there is no requirement of energy, this ATP will be converted into ADP. So like this was adenosine triphosphate. So this is adenosine diphosphate. What should we call it diphosphate? So this becomes adenosine diphosphate. Meaning that a phosphate molecule has come out from here. Now when there will be a requirement of energy again, another phosphate will be added to this ADP and this will be formed. So that means ATP is what ATP will do when there is no requirement of energy, it will be converted into ADP and when there is no requirement of energy, it will be converted into ADP. If there is a

10:54 requirement, then these two will again combine together to form AT which is the energy currency of the cell and all the activities that are happening inside a plant, in fact in animals too, for each and every activity we need a lot of energy, right, so it was simple to understand till now, you understood the characteristics, if you have any doubt about respiration, then please ask them on the ask question section of learn.com, okay, so let's move ahead, so here are the metabolic activities, I have heard a lot about metabolicism, nowadays it is very much in trend, I mean staying fit, so nowadays it is very much in trend, okay, many people go to gym, do yoga, do a lot of things to keep themselves fit, so

11:40 here come some metabolic activities, some such activities where there are two steps, now metabolism has two steps, one is anabolism and the other is catabolism anabolism means to consume something, to make something, means some small small We have ground them and mixed them to make a big piece. So this means anabolism is a constructive activity. And what is this? This is a bio-synthetic process.

12:26 Now this is such a process where things are being formed. Some small things are combined to form a big thing. So what do we need to perform this step? We need energy. So over here energy is required. The second step in metabolic activities is catabolism. So catabolism represents destruction. And these are the destructive activities. So these are destructive or these are breakdown activities. So what will happen here? This is a big thing which was constructed.

13:11 Now we will break it down into small steps. So you remember we had read about the digestive system in humans. So what was there was that we were taking food. Okay, we were eating food. Now it is in a very complex form. So now we cannot release energy directly from starch. So this starch is broken down. It was into smaller and the simpler pieces that is glucose so this is the step where a big thing is being broken down into smaller pieces so we will call it catabolism okay so this is the energy where sorry this is the activity where energy is given out okay so it means

14:02 that two activities are happening within metabolism anabolism and catabolism things are being formed in anabolism so when things are being formed then energy is being used there so it means that there is requirement of energy to perform anabol activities and on the other hand when catabolism is happening then things are getting broken down so in that case when things are getting broken then energy is getting released from them so energy is released in catabolism right so I hope this is clear next if I ask you now after doing this basic study that what is respiration then what will you say so respiration is basically a process of breakdown in

14:47 which Living cells are oxidative and organic substances like glucose that release energy. So carbon dioxide will be formed here and water will be formed and a lot of energy will be released here. So respiration is what type of a process? It is a catabolic process releasing energy from glucose to carry out all the life processes in our body. So if I show you a quick recap once, this is our cell. Inside the cell, there is the nucleus. Okay, we have shown the nucleus. Inside it, there is this double membrane cell organ which we have shown as mitochondria. Okay, so what will happen is that whenever

15:33 glucose comes, the glucose will first come here and the glucose will be converted into pyro fat. So where is all this step happening inside the cytoplasm. Now this pyro fat will go here in mitochondria and energy will be released here. Okay, so this is the breakdown of glucose step, right? So I hope I am clear to everyone. Now let's move ahead where first we will take a question and the question is very simple, just keep the options in mind. Read the answer from this you will tell ok so glucose is a process sorry not glucose so glycol is a process in which glycogen is broken down into glucose so here are

16:19 we breaking glycogen into glucose what kind of process was it no so here we are breaking glucose into pyro weight clear so this statement is wrong than it happens which happens in mitochondria so where does this happen all these steps happen inside the cytoplasm clear the next is in which glucose is broken down into pyro weight so this is a correct step sorry an option correct now that happens next to crab cycle so no first there will be glycolic and after glycolic there will be crab cycle so now all the

17:07 pyro weights that are formed here will enter in glycolic and in mitochondria there will be crab cycle clear so I hope this is clear the next is a very important to understand the difference between respiration and burning so What is the difference between respiration and burning? Look, both are such processes in which carbon dioxide is being released in a way, but if we talk about respiration, where is respiration taking place? Inside the cells of the body, that is, inside the living cells, so it is a kind of cellular process. Burning means that you have burnt something, is that burning process taking place inside a cell? No, so this is a burning is a non-cellular process. The

17:55 next is respiration, it occurs at body temperature. So whatever this process of respiration is, it occurs at our body temperature. That is, our normal body temperature, if I talk about humans, it is 37 degrees Celsius and in plants, this entire process occurs at the same temperature as their body temperature. But if we talk about burning, when we go near fire, it feels very hot, right? Because high temperature is required there, only then the process of burning can take place. Then the next is it occurs in A series of chemical steps. There are many steps through which energy is released. In respiration, we have read that glucose has to break down. So

18:40 what is glucose? Glucose will go inside the cell and go to the cytoplasm. So what did glucose do? Glucose went to the cytoplasm and after going to the cytoplasm, it got converted into pyrovate. And here, this process where glucose is getting converted into pyrovate, this entire process has 10 steps. Pyroovate is not formed from glucose immediately. After that, this pyrovate enters the mitochondria. And here, the Krab cycle takes place and energy is released along with carbon dioxide and water. So here also, this entire cycle, the Krab cycle, is a series of

19:27 steps through which carbon dioxide will be released at every step. Water will be released somewhere and energy will be released somewhere. So this is usually a series of steps. Burning is a very simple, single step process. Then, respiration is carried out by enzymes. So, we have read that What was the second characteristic of respiration that we need a particular enzyme. So when you go to higher classes, you will study glycolytic, you will study the crab cycle, then when you will study each process, then you will come to know that in each step, like I have written here that there are 10 steps by which glucose is converted into pyrovate, then in each of the 10 steps, 10 enzymes are

20:15 required here, then conversion of glucose into pyrovate takes place, here enzymes play a very important role, but in burning, only heat is needed in burning, right, so we can also call burning combustion, okay right, so let's see further, so now if we talk about respiration again, then respiration is a biological and chemical process, so we will call it a biochemical process, while burning is a physical and chemical process, okay then energy is liberated as ATP and some heat, so whatever energy is being liberated in Respiration is in the form of heat and

21:02 mostly it is in the form of ATP and this ATP is what we are using or the living organisms are using then if we talk about burning, all the energy that is being liberated is in the form of heat and the warmth that you feel when you go near the fire, along with that there is another thing there which is light right then in respiration no light energy is produced so there is no light energy here but in burning light energy is also produced right so I hope the difference between respiration and burning is clear to you if you have any doubt if you have any doubt in any step please ask them on ask question section correct okay so let's move ahead now parts of respiring plant so does respiration

21:49 mean that there is a leaf there are small pores in a leaf and through these pores oxygen will go in and carbon dioxide will come out is this a single step or an inlet or a single place where Respiration is taking place, so no respiration takes place through three inlets, one is stomata, so I have described an enlarged version of this stomata here, so what will happen here is that when this stomata opens, oxygen will go in and the cells will respire dioxide will come out, along with this, the lente cells which are the stem of the plants have some such small pores on the stem which we

22:36 call lenti cells on the stems, so respiration also takes place from the lenti cells, then the general surface of the roots, so respiration also takes place from the roots, the roots also take in oxygen and the roots also respire, so no, there is no single respiratory organ like we have read in humans that there are lungs, then a lot of big tubes are connected together, but here every plant part has low energy requirements because it does not move, right, so here there is no diffusion, the energy, so gases are transferred through the process of cell to cell diffusion It happens from one cell to another and this is how the gases keep getting transferred but here in

23:21 case of plants there is one more very important thing so you must have seen that whenever we plant a plant or a seed, that means whenever we have any plants or seeds, when we plant them in the soil, then after that we regularly plow that soil, okay, keep tilling it so that the soil remains loose and the roots can breathe, so the roots respire, if the soil is very tight then there will be no air spaces, if there are no air spaces then the roots will not get air because every plant part is not a respiratory organ by itself, so the

24:06 plant dies due to the roots, so always a plant or a farmer or a gardener keeps loosening the soil so that air spaces are created there, air goes there and the roots of the plant keep taking oxygen and keep releasing carbon dioxide, so there is respiration there The process should run smoothly and the other reason is that if the soil is very tight, then there will be water clogging and the roots will get damaged due to it, so our plants will not be able to grow, correct so I hope this is much clear to everyone, if you have any doubt, please ask it on the ask question section, okay, so go ahead respiration during day and night, so

24:54 what is the difference between respiration during day and night, so look, respiration is a process in which energy will be released, okay, now the gases are evolved for this energy release, so during the day there is a process which does not happen at night, which is photosynthesis, so what happens during the day is that when the stomata open, when these pores open, then the plants take in carbon dioxide and release oxygen, so a lot of oxygen is being released in this process, so if you are sleeping comfortably under a tree during the day, then at that time you are getting a lot of oxygen because the plant produces a lot of oxygen It is releasing oxygen and along with that the transpiration is also taking place with the air, so

25:40 you get a cooling effect but what happens at night time, at night this whole process gets reversed so what happens in this process is that plants take in oxygen and release carbon dioxide so what will happen if you sleep under a tree, by sleeping under a tree you will not get oxygen, you will get carbon dioxide and it is possible that you may not be able to breathe, okay, so earlier it was said that one should not sleep under a tree at night because there are ghosts in the tree at night there are no ghosts but they release carbon dioxide which is not a breathing gas for us, okay so I hope this is clear, so let's move ahead,

26:27 so now coming on to the two kinds of respiration, there are two types of which There are two respirations, so one is aerobic and the other one is anaerobic. So aerobic respiration is such a respiration where there is a complete breakdown of glucose into what? Here enzymes will be required and complete breakdown will happen into carbon dioxide and water and a lot of energy is released. So around 38 ATP molecules are released during aerobic respiration. But this is aerobic respiration because oxygen is required here and the entire process takes place in the presence of oxygen. So

27:13 we also call it oxy biotic respiration. Here glucose is engulfed so it is C6H12O6 so there will be incomplete breakdown of this glucose in the absence of oxygen. So here ethanol will be formed, C2H5O plus carbon dioxide is released and a very little amount of energy is released. So this process is here because oxygen is not used, so there is no complete breakdown of glucose. And if the energy is also used very less, then any part of the plant has to live temporarily during the

27:58 enrobed period, because it is released in aerobic respiration, so its energy requirement will not be fulfilled, so finally that plant or that plant part will die. Now here, because the energy that is being released or the process is happening in the absence of oxygen, we call it anoxic without oxygen, some biotic process is okay, and the respiration, these

28:44 whole steps happen in many plant parts but happen temporarily, but there are some micro-organisms like bacteria, they depend only on intestinal respiration, meaning they do not have aerobic respiration, so they can live, but those parts that require oxygen for respiration, they cannot respire during the period of time in the absence of oxygen, so let us now understand the difference between aerobic and aerobic respiration. And anaerobic respiration so aerobic respiration is a respiration that takes place in the presence of oxygen and there is a respiration that

29:31 takes place in the absence of oxygen that is anaerobic respiration right now here the complete breakdown of glucose takes place in the case of aerobic glucose that is c6 h12 o6 it gets completely broken down into carbon dioxide water and lots and lots of energy is released but here the glucose breaks down into ethyl alcohol and this is an incomplete breakdown the next is the end products are carbon dioxide and water over here the end products are ethyl alcohol and carbon dioxide so these are the same things that we just read in the form of reaction the next is energy is

30:17 liberated in large quantities so how many molecules here did we read that is 38 ATP molecules and in the case of an aerobic respiration energy is liberated in less quantity that is just to ATP Molecules are formed right so remember the reaction that we just did and read, okay so next aerobic respiration is what happens normally through out life in the case of plants but anaerobic respiration happens temporarily when there is requirement of energy somewhere and oxygen is not able to reach there or is not able to reach in sufficient amount, so in the case of plants we are immersed as now take up some experiments, so when we

31:05 talk about experiments, it has become important for us to understand two things now the first thing is the experimental setup and the second is the control setup, what is the difference between the two, so both are almost the same, meaning whatever setup we have made, it will remain the same, accept one thing, suppose we are talking about respiration here, so we have to prove that when plants respire, they use oxygen, okay, meaning they need oxygen, so what will we do at that time that In the experimental setup, we will keep everything normal. So oxygen will also come to the plant and all other conditions will also be normal. But in the control

31:53 setup, this is the only thing. Here in the control setup, we will make oxygen limiting, meaning we will not let the plant get oxygen. Only then will we understand the difference. That oxygen is coming in the experimental setup and not coming in the control setup. So is it actually making a difference to the plant or not? So here only one thing makes a difference and that is the same thing for which we are doing the experiment. To prove this, we are doing the experiment. So I hope this is clear. So now let's start with our experiments. So let us see what is a first experiment. So let us start with our first experiment. So in this experiment, we have to prove that oxygen is used in respiration. Meaning oxygen is used or

32:39 oxygen is consumed. So what will we do here? We have taken two setups. Setup A and setup B are almost the same, one is experimental and one is control, as we discussed, here we have taken two conical flasks and we have put wet cotton in both the conical flasks. The difference is that when we put germinating seeds in setup A, which is our setup A, we have put dead beans or boiled seeds from wee cans. So, we have kept both these seeds on wet cotton. Now, because the boiled seeds become dead after biotic, we have put an antiseptic here

33:25 so that bacterial growth does not take place on these seeds. Now what did we finally do? We took two test tubes, suspended both of them in these conical flasks and put soda line clear in them. Now what we have to do here is we have to prove that oxygen is being consumed in respiration. So, now what we will do is we will make both the setups absolutely air tight and then fit the corks. We will give it to the seeds so that the air cannot go in or out and we have taken delivery tubes from both and we have connected them to another beaker which has water in it. So basically we have dipped those delivery tubes in water. Now what will happen is that after some time we will see that the

34:17 water level of this delivery tube which is connected to A has risen more and in B it is less. What happened in setup A? In setup A there were germinating seeds. So what did the germinating seeds do? They used up the oxygen and released carbon dioxide. So this carbon dioxide, this oxygen has been used and carbon dioxide has come out. Here in the MT spaces it is fine. But in B there were dead seeds. So the oxygen has not been used here. But what has the soda lime done in the carbon dioxide? Now all the carbon dioxide that was there has been absorbed. It is fine because the oxygen has been used from the air. So here the water in the delivery tube will rise upwards. So now some

35:03 questions arise here. The first question is this. That we have used antibiotic which is carb carbolic acid what is carbolic acid carbolic acid is basically a mixture of sodium hydroxide sodium hydroxide and calcium oxide so we are using this because these are boiled seeds, dead seeds so there can be bacterial infection on them bacterial growth can be seen so to avoid this bacterial growth we have used antibiotic here secondly test tube containing soda lime is suspended in each flask which is a test tube containing soda lime right why have we added it because what we did was we

35:49 took a conical flask and put a test tube in this conical flask which has soda lime so using soda lime means that it absorbs the carbon dioxide which is being released from the seeds when oxygen is being used and carbon dioxide is being released during respiration so what have we taken here to absorb this we have taken soda lime here next question comes Is that why there is a slight increase in the level here because oxygen was not used in boiled C, in test tube B oxygen was not used because there were boiled seeds there which were dead seeds, so why did the water rise here, the water should not have risen, so there are

36:36 two reasons for this, the first reason is its capillarity, what is the reason for capillarity, so in the tube, now suppose you open a bottle of coke and put a straw in it, then without sucking what will happen here, the level of water will increase a little, it will happen, that means a little soda or coke will come in the straw, right, so the same thing has happened here, that is capillarity, the second reason is that when all the carbon dioxide is used up and all of it is absorbed by the soda lime, then now a vacuum is created here and due to the creation of this vacuum, there is a little pool of water, so

37:23 we have seen that there is a slight increase in water. In the B setup at the level, okay, so which is the control setup here? So we had to prove that oxygen is used during the process of respiration. So what happened in the A setup? In the A setup, we saw completely properly that the seeds used the oxygen and released carbon dioxide, but what have we done in the B setup, we have taken dead seeds, so they are not using oxygen at all, so the oxygen is remaining as it is. So now in the case of both of these, if you take a burning paper, open the cork and take both the burning papers to the mouth of both the conical flasks, then you will see that the fire in the A setup will be

38:08 extinguished, but in the B setup, this fire will not stop because B is full of oxygen and what is there in A is that the oxygen has been used and now there is only carbon dioxide which has been released by the germinating seeds. So this means our control setup is the B setup. Okay, and let's see. The next one is we have to Prove that carbon dioxide is produced during respiration in the germinating seeds. So here we have taken germinating seeds and boiled seeds, so what will be boiled and what will be dead seeds, in both we have put both kinds of seeds on cotton wet cotton wet cotton. Now what will we do,

38:55 let this setup remain like this for some time, but we will fit a cork here, so by fitting the cork, neither extra air will go in or out here, the air that is inside will remain inside and it will not go out and neither will it come in from outside, so what will happen with this, our seeds are there in a setup, this is setup A and this is setup B, so what will happen in a setup is that these seeds will use oxygen and will release carbon dioxide and what will happen here, the air that is there will remain as it is, okay so that is a mixture again, now what we have to do is after some time we will first open one cor, we opened one cor, so as soon as we put it on top of the test tube of lime water like this We will tilt it, right?

39:42 Because what will carbon dioxide do to heavy water? We have been studying this since childhood. So it turns lime water milky. But when we pour the B test tube over the lime water, we will not see any milkiness here. So this shows that the germinating seeds produce carbon dioxide. So I hope this is clear. So we have another experiment to prove that carbon dioxide is released by the germinating seeds. So what we have done is we have taken four conical flasks and attached them to each other using the delivery tubes. So here, first of all,

40:27 air is coming from outside, which is carbon dioxide free air, it will go into our A setup. It will go to A conical flask. From A, the air will go to B. From B, it will go to C. From C, it will go to D. And from D, it will finally go out with the suction pump. So this is our setup. What have we done in this setup which is A conical flask? This is a flask, even all the conical flasks, what have we done in them, we have fitted some cores so that no air from outside comes in nor goes out from inside. So what will happen here, now here when we introduce carbon dioxide free air into this first conical flask that contains K solution, so if this air is

41:16 contaminated with carbon dioxide in any way, then this carbon dioxide will be absorbed by K solution. Now when the gas passes from here from a conical flask to B, then we have kept lime water in B, so now it will be checked here whether this air contains carbon dioxide or not. If this lime water turns milky, it means that there is carbon dioxide in the air, but in our case the carbon lime water did not turn milky, it means that there is no carbon dioxide in this air. Now we let this air pass from B to C, so in C we had germinating seeds, so when the air reached the germinating seeds, this air contained a lot of oxygen. So

42:03 what did the germinating seeds do? They took in oxygen and produced carbon dioxide. Now when this air goes into the next test tube, from here it goes into this C. Okay, sorry not C but D. So when it goes into D, we have again put lime water in D. Now what will happen is that when carbon dioxide rich air comes into the lime water, then this will turn into milky white. So this shows that the germinating seeds produce carbon dioxide while respiration. I understood, it was simple, right? Let's see another experiment. So let us come to our next experiment where

42:49 we have to prove that when the green plants respire and produce carbon dioxide, then respiration is basically a process in which oxygen is being used and carbon dioxide is being produced. So what have we done here, we have taken a setup in which we have taken a small plant, a small potted plant, and we have put it in a bell jar. And remember this has to be complete. This whole jar should be completely sealed, there should be no air contamination in any way, air should not come in from outside in any way, the air that comes into the bell jar should come and go only through these delivery tubes. So what did we do? We took a bell jar, put a

43:34 small potted plant in it, sealed it properly with a cork and fitted two bell jars, sorry conical flasks, on both sides. The first is a conical flask which we have called A. In this, we will pass the air that comes passing through the soda lime. Basically, what will happen there is that whatever amount of carbon dioxide is there in this air, it will get absorbed. We need air in which there is no carbon dioxide. Now, when we pass it through lime water, the lime water will not turn milky. So, this will give us a clarification that the air in the experiment that we are going to do is carbon dioxide free. So, we have only used carbon dioxide. We

44:21 know why we do n't need carbon dioxide, so that if there is already carbon dioxide, then how will we know that the green The plants have produced this carbon dioxide. So the air that comes in should not contain carbon dioxide. So we have to prove this as well as confirm it before putting this air in the bell jar. So here we passed it through lime water. The lime water did not turn milky. The lime water remained completely clear. So now this air will go into this bell jar. It has come here. Now there was no oxygen in this air, so the plants used the oxygen and produced carbon dioxide. Now this carbon dioxide will go through this delivery tube, that is, this air that contains carbon

45:08 dioxide will go through this delivery tube to flask B here. So we have again kept lime water in flask B and now the lime water will turn milky. This shows that the air that has come here now has carbon dioxide present in it. So one thing is very important here, that is this first thing. I have told you the first thing that the bell jar setup should be completely sealed and secondly The important criteria is that you will do this entire experiment in dark conditions, it is okay, it should not be done in light, otherwise what will happen is that when carbon dioxide is produced here, then this

45:55 plant will use this carbon dioxide in photosynthesis in the preparation of starch, so that we have to do this entire experiment in the dark, if you are not doing it in the dark, then at least cover it completely with a black cloth so that in no way the light can reach this green plant, understood the thing, it is simple, understood how we have to do this experiment where we have to tell that when there are green plants, they produce carbon dioxide and why we have fixed this setup in the dark, it is clear, so let's go towards another experiment, so now we had discussed one more thing that when respiration takes place, energy is released,

46:42 but some energy is in the form of ATP and some is in the form of heat, okay, so it is difficult to extract ATP from such an experiment It is difficult but we can detect the heat very easily. How will we do it? So we need two flasks, two thermos flasks and what we will do is take some seeds, some bean seeds and soak them in water for 24 hours. Then we will keep half aside and boil the other half. So what will happen when we have only soaked the seeds here in our setup A and the ones here are the

47:27 boys, the soaked seeds are living but the boys become dead clear. So now we have put both of them and now we have also put wet cotton wool on the mouth of the thermos flask. So it means that the seeds are getting water here and it is fine. And we have fitted thermometers on both sides. So we have set separate thermometers in both the flasks. Now what will happen is you will let it remain for some time. Now these seeds are getting the right temperature and water as well. They are getting oxygen and now what will they do, they will also respire, so what will happen here, what will happen with respiration,

48:14 heat will be produced from respiration and when this heat is produced, the temperature will increase, so that is why the mercury in the thermometer of the germinating seeds will rise more and the mercury of the dead seeds will not rise, so this shows that the germinating seeds produce heat, so it was simple to understand, let's go ahead and see the next experiment, it is very interesting, so in this chapter you will have experiments which will prove everything to you, so I hope you are able to understand till now, so remember a very important thing, whenever you are experimenting with dead seeds, it is

49:00 very important to wash these dead seeds in antiseptic, so if you do not wash them in antiseptic, if you do not clean them, then bacterial growth will happen here. This can happen and your results can also vary due to bacterial growth. So, so that any kind of microorganism does not grow in them, you always have to wash the dead seeds with an antiseptic. Mmm I am clear to you. Let's go to our last experiment. Now the last experiment is to demonstrate anaerobic respiration. Some respirations can also happen in the absence of oxygen. So this means that carbon dioxide will be released here. So what we have to do is we have to make a setup in which we have to

49:48 take a test tube and we have to fill this test tube with mercury. So remember mercury is quite dangerous, not that I can say dangerous but it is poison as well. So we have to take a test tube containing mercury and fill it with mercury. And now what we will do is we will put some seeds in it. We have taken pea seeds here and what we have done to the pea seeds is we have peeled them, we have removed the outer covering. So what happens with this is that when The diffusion of seeds will happen quickly towards the outside, that's why we have taken peels seeds. Now what we will do is we will invert this test tube on to a beaker in which there is mercury again.

50:34 The symbol of mercury is Ag. So I have written Hg here. You have to remember it. So what will happen now? Let this experiment and this setup remain like this for two-three days. After two-three days we will see that the level of mercury here has dropped and a space has also formed above the seeds. And this gas in this space is carbon dioxide. Now you will say how will we know that this is carbon dioxide gas. So you will take a strip of potassium hydroxide that is K and dip it into this mercury. So all the carbon dioxide present here will be absorbed. So what will it do? It will absorb the carbon dioxide. Now what will happen with this will make it

51:21 clear that there was only carbon dioxide here because the level of mercury It will again become like it was in A and the level of mercury which had dropped in B will now become like A. So this means that the space above has become empty and the mercury will rise again upwards. Now it is very important to keep in mind that when this experiment is being done, one has to take precaution that one has to keep oneself safe from mercury. So I hope this is clear. You can do this in the control set setup that the setup will remain such that you will take mercury and now if you put boiled seeds in it, then this drop in the level of mercury in the boiled seeds will not happen. So this shows that

52:07 carbon dioxide has not been produced there and the seeds have not produced respirable dioxide either. So, therefore, the mercury will not dip. So I hope this complete experimental series is clear to you. If anyone has any doubts, then don't. Please ask them on ask. Question section Even the smallest doubt can come in the exam as a question so don't don't keep the doubt in your mind just ask it out on the ask question section of learn.com let's move ahead so let us now take up some questions so the questions are the name of the following first is the energy currency of the cell so what is the energy currency we call ATP next is

52:52 oxidative breakdown of carbohydrates to release energy when we oxidatively break down carbohydrates and extract energy from them so we call that process the same which is the name of this chapter that is respiration clear next is an organism which respires through out life aerobically so aerobically which organism is which through out life which enrobes so that is one of the organisms is fungus clear next is a common phase in both aerobic and anaerobic respiration which one was I had told which one was it Was glycolysis a process where even oxygen is not used. Tell me quickly where does it happen?

53:38 In which part of the cell does glycolysis occur? Quickly, right, it is the cytoplasm. Okay, let's move ahead. So now let's discuss some differences between photosynthesis and respiration. So photosynthesis and respiration are actually opposites of each other. In one, glucose is being produced and in the other, glucose is being broken down. So what are the other differences between them? So it occurs in the presence of chlorophyll. That means chlorophyll is needed for photosynthesis. But here, chlorophyll is not needed. It occurs in all living cells. Respiration occurs in all living cells. So, in a plant, photosynthesis will only occur where there is chlorophyll. Respiration will occur in all cells. Right then, it occurs

54:24 only in the presence of light. So, just like chlorophyll is a very important raw material for photosynthesis, sunlight is also important. If we talk about respiration, then we do need sunlight for it, otherwise whether it is day or night, when a cell needs energy, then a cell needs respiration, so they respire and the cells respire, next is in photosynthesis they use carbon dioxide and water where as oxygen and glucose are used in respiration, okay next oxygen is released as the end product, so here oxygen is a byproduct

55:10 but in case of respiration carbon dioxide is the byproduct, okay so what will happen here, in photosynthesis we will use carbon dioxide and water in the presence of sun and chlorophyll and what will be formed here glucose plus what will be released oxygen and what will happen here will be exactly opposite here glucose will use oxygen and release carbon dioxide and water and here a lot of energy but no root matter that is enzymes will be used, okay so this thing is understood, later there are few more

55:55 differences the light energy is converted into chemical energy In photosynthesis, what is stored? Okay, there the chemical energy is partly converted into heat and partly into useful energy. So what is happening here? We have seen that whenever respiration takes place, some energy is released in the form of heat and some energy is used to form ATP. So in photosynthesis it results in gain in weight while in respiration it results in loss of weight. Correctly, in photosynthesis food is being prepared and in respiration food is being broken down. So now we have read one thing, types of metabolic reactions. Okay, so

56:41 we have read two metabolic processes, anabolism and catabolism. So which one is anabolic and which one is catabolic. What is anabolism, constructing or making something? So according to that, photosynthesis is an anabolic process. Okay, there breaking down of things is catabolism. So what is this? This is a catabolic process. Okay, so everyone understood, so what we have is two. We needed examples of anaerobic and catabolism. We understood that. Very good. If you have any doubts, please ask them in the ask question section. Okay, let us now understand the difference between respiration in plants and animals.

57:27 So, if we talk about plants, we have not seen any kind of gaseous transport in plants. We have said that there is no cell-to-cell diffusion here. Okay, whereas in the case of animals, there are many tubes in our body, bronchi, bronchioles and lungs. So, there is no transport of gases here and it does not only come from these tubes but it goes into the blood in our body and the blood transports the gases. Then, next is plants. So, in plants, the end product of anaerobic respiration is ethanol and ethyl alcohol. So, that is one and the same thing. What is C2,

58:15 A5? But, if we talk about animals, then these are the end products. When is lactic acid formed? When is lactic acid formed? When you are running very fast and now your body needs energy to maintain that speed, but you are neither able to take in oxygen so quickly nor is your body able to produce energy, so at that time the glucose quickly breaks down into lactic acid and you get energy. Alright, the next one is plants produce a little heat, whereas in case of animals, a lot of heat is produced during respiration. So this was all from today's session. I hope you enjoyed the session. I hope you liked the session. I hope you understood the session. So now if you have any doubts, please ask them

59:01 on the ask question section of all hub.com till then you all take care, we will meet next time and as you all know, Learn Hub means it is free but it is the best.