Transcript for:
Overview of Breathing and Gas Exchange

hello my dear students and welcome back to victory batch and i am your dikshama so today we are going to start with the chapter breathing and exchange of gases a very important chapter from neet point of view you know there is a trend in human physiology from every chapter of human physiology they ask at least minimum one to two questions so why to leave them let's get started so first of all what is breathing and what is respiration you always hear these uh these two words breathing and respiration what's the basic difference between them in breathing you're just taking in the air and leaving out the air right you're just inhaling and exhaling like right now we all are doing like just like this but what about respiration with breathing you have taken in the air and that ear have oxygen and that oxygen goes to your tissues and tissues burn the food with the help of this oxygen known as oxidation and gives you energy this is what your respiration is so in the breathing we take in we take in we exhale or inhale right it's basically just a mechanical process you're taking in the air and you're exhaling in the air inhale or exhale the air whereas in the respiration in the respiration it involves oxidation of food oxidation of food to produce energy to produce energy right all right so this chapter is all about breathing and respiration now what are the various types of respiration there are two types of respiration one is direct another is indirect so what happen in the direct respiration this occur in the simple organisms in which organism which are quite simple their body is not so complex guys just like we have amoeba amoeba is just single cell animal it's in the single cell animal there are no lungs and no guilts nothing like that so oxygen will directly get diffused through the body so in this direct diffusion takes place from the body direct diffusion of gases right like we have amoeba like we have the poriferons or sponges so what happen in these organism if this is organism directly the oxygen will come and co2 will move out and the cell or the organism will do what it's doing its respiration breaking down the food whereas in the indirect one what happened in the indirect one the body is complex body is complex imagine in us first of all there will be exchange of gases in the lungs and then from lungs the oxygen will go to your body tissues and this is how the respiration takes place so the body is complex the breathing or respiratory organs are present respiratory organs are present right you must also have heard about another type of respiration that is aerobic and anaerobic let's talk about that now we have aerobic respiration and then we have anaerobic we have aerobic respiration respiration is further of two kinds guys one is aerobic and another is anaerobic so aerobic is the one that we do what is aerobic respiration first of all aerobic wherever the word arrow come that means it's related with oxygen so in the aerobic respiration oxygen is used here oxygen is used co2 is produced co2 is produced so when you will oxidize a glucose it will form the co2 in water and also it will form the energy and the energy content in these two if we compare aerobic one produces more energy as comparison to the anaerobic one so this produces more energy produces more energy fine in the anaerobic one less or basically no oxygen is used basically no oxygen is used here the oxygen can be present or absent but the oxygen will not be used it's better to write no oxygen okay so here no oxygen is used so here co2 may not be formed but the energy will be less than the aerobic one energy produced is less so what are the example first of all in us do we do anaerobic respiration yes certainly we do so anaerobic respiration takes place in our skeletal muscle in skeletal muscle whenever you have low oxygen condition or you're running very fast you get cramps why do the cramps are formed because whenever the glucose get burned in the absence of oxygen it will not produce co2 it will produce lactic acid also in our rbc in our rbc alcohol is produced yes irbc does not have nucleus it does not have mitochondria so it will undergo anaerobic respiration because an error in the aerobic respiration you need mitochondria but in rbc mitochondria is absent yes so this must be a surprise for you ma'am rvc yes they also undergo anaerobic respiration so we have rbc here what are the other example endoparasites in our body endoparasites like ascaristina yes they also undergo anaerobic and they also produce alcohol yeast fermentation yeast also produces alcohol and then we have cellulose fermentation cellulose fermentation all these are the example of anaerobic respiration so in this obviously in this chapter we are talking about humans so we'll be talking about the aerobic respiration in the entire lecture so first of all let's see what are the various respiratory organ in the entire animal kingdom so guys wherever i put star the question can be asked from this topic okay so in the respiratory organs how does the respiratory organs different in different organisms for example right now wherever you're sitting there must be some ants going on right or run your ants are running here and there right so ants are insects so they have different kind of respiratory organ we are different we have lungs if you'll see in the water organisms have different types of respiratory organ so why different types of animals present on the same planet have different types of respiratory organ the reason is first of all their habitat you are living on land whereas fishes they are living in water so basically if the habitat is different the mode of respiration will be different second the complexity and is a simple organism comparison to us so according to the complexity of organism they have different types of respiratory system like in sponges in sponges the the complete organization is cellular level no complexity at all so they uh respire through simple diffusion and what about us we have lungs we are quite complex we are mammals so we respect through lungs so respiratory organ the types of respiratory organ depends upon first the habitat of organism and body complexity of organism body complexity of organism let me show you with the examples and guys this is really important because you know this is a kind of a topic that falls into two categories of chapters one is animal kingdom another is breathing in exchange of gases then why to leave it all right so let's get started with this one in the flat worms in the body ference and cilian trait you can see all these organisms they're quite simple they have a you know cellular level of organization they have tissue level of organization and these flat forms since their parasites and organ level of organization is still there but they are parasites the body is quite different right so all these will respire through simple diffusion over their entire body surface for example if this is a poriferan right so here oxygen can enter and co2 can leave directly through the body just like that here co2 will leave and oxygen will enter similarly with the cilian rate so all these organisms what flatworms poriferance and they respect through simple diffusion fine next earthworm earthworm if you've ever seen earthworm i don't know what it is said in your language let me know in the comments from where do you belong and in what language do you say earthworm for example i am a punjabi so in punjabi call it as gandua right so earthworm if you'll see anywhere in the soil it usually comes out during rainy season from the soil and they are very slimy they have a slimy body and it's very shiny right it's just like it has a mucus layer on it so its skin is quite moist that means it has more water content fine so it has very moist cuticle or skin so this type of respiration can directly take place by the skin so you will not call it a simple diffusion yes simple diffusion is occurring here but skin is the mode of respiration because skin had blood vessels and from the skin the oxygen will go to the blood vessel then to the tissues how it is different from the this from this one here diffusion takes place and oxygen directly got diffused into the body tissues in this one from skin the diffusion will take place and then the oxygen will enter into its blood vessel into its blood vessel and from blood vessel it will then go to the tissues okay this is how it is different so here the type of respiration that takes place through moist cuticle or skin you call it as cutaneous respiration so in earthworm what type of a respiration we have cutaneous respiration that takes place through the skin fine next one then we have tracheal tubes the trachea these are small tube-like structure they are innervating the body tissues and they have these small openings known as spiracle so spiracles are opening through which the oxygen enters and through these tubes it goes to the tissues and this type of arrangement you can see it in the insect so an insect the best example we have is cockroach so we'll be we have already studied the cockroach guys so in cockroach we have this type of system then we have gills so guilts are seen in aquatic animals so in these type of gills which are not that developed they can be seen in aquatic arthropod and mollusk see insect belongs to the phylum arthropoda but insects are terrestrial but there are certain aquatic arthropods let me give you an example like prawn they respire they respire through the gills fine also malas they respire through gills then we have the aspiratory organ in vertebrates earlier all those organisms they were invertebrates they are the vertebrates one so first of all we have gills in the fishes these are the highly developed organs known as skills so these are gil's epithelium from here the in oxygen can enter because gills take up the water and water have a lot of oxygen so from gill epithelium the oxygen can easily diffuse into it right so for fishes we have gills then we have lungs lungs and amphibians reptile avian and mammalian so if you can see here what's the course of evolution what you say these are the less developed more developed more developed quite different highly developed right so similarly in amphibians amphibians can respire through lungs guys they can also respire through skin and the respiration that takes place through skin is cutaneous respiration that takes place through gills is branchial branchial respiration that takes place through skin is that takes place through the skin is your which respiration that is your cutaneous the vantru gills bronchial and the one through lungs okay the one through lungs is pulmonary what do you call it as pulmonary okay so amphibians are special they can respire through lungs through skin and through bucco pharyngeal cavity that's their buckle cavity buckle cavity okay it also have a very moist skin and last gills so gills are seen in aquatic amphibians and the larva which are tadpole which are tadpole fine then we have reptiles and reptiles we inspire through lungs and eve saves means birds we also just reptiles through lungs but they have additional these sacs known as air sacs the function of air sac is to get more air inside the lungs and supplement the respiration to increase the respiration see if we also get some these additional chambers we can get more air just like that nature has given them the ear sack to get more air two benefits one they will get lighter and they can easily fly second in flying they need more energy for more energy we need more respiration because when we break down the glucose only then we'll get the energy so that's why these air sacs are present in the avian lungs and then we have mammalian lungs so these are the various types of respiratory organs in the different types of animals let's talk about human respiratory system so the entire human respiratory system is divided into two parts one is the respiratory passages another a respiratory organ and what is our respiratory organ lungs we have one pair of lungs if we talk about the respiratory passages these are the small passages from where your air enters and goes towards the lung so let's talk about them in the detail so if i talk about lungs where it is present this is a chamber it's a thoracic chamber or a thoracic cavity thoracic cavity and this is abdominal cavity or abdomen thoracic cavity and abdominal cavity how you demarcate it you demarcate it with the help of this flap-like structure known as diaphragm so diaphragm is a muscular flap guys diaphragm is a muscular flap it's a muscular flap and this muscular flap helps in the demarcation or dividing this cavity the thoracic and the abdominal in the thoracic cavity you can find these two pair of lungs like this two pairs of lungs so what are these lungs this is one lung this is the another one right so this is the exact location of your lungs let's talk about them in more detail so we'll start with the respiratory passages first because we'll go through the root of the air so what do you think from where do you respire in the you know uh when you are very little when you you were like pre-school kid at home usually our mother and our father or our brother sister they teach us this is nose this is i this is ear later when you grow up more they started teaching you from where do you breathe you breathe through nose this is what uh your teacher teaches you right in school so we get to know that we breathe through nose okay so uh the air enters through these small openings what do you call them as nostrils or nairs what do you call them as nostrils or nails might a lot of you must or do not know about these in english nobody's when i was at your age even i got to know for the first time that's the that these openings are known as nostrils in english because i belong to that area where we do not you know get to have a lot of exposure for the english language so you must be surprised none but you speak really fluently and you're teaching in pw english that's the hard work i did on myself in those years i i watched a lot of english movies and documentaries so that i could increase my skills so you can also do the same nothing is impossible in life you don't need the always you do not need the external factors sometimes your internal factors can also lead to a lot of determination and that's enough for you to learn anything you know i i always have determination to learn new things like eating with the chopsticks so you know what i used to do i used to buy uh noodles of just rupees 20 and i bought two chopsticks at a very cheaper price and used to practice at home so this is how you learn things you should have your inner ability and determination to learn things anything is possible anything is possible your other factors are not the paths of determination when the determination comes from the inside right okay so these the small openings they are known as external nostrils external nostrils or nairs so the entire this uh this external nostril lead to the inside of the nose and you call it as nasal cavity nasal cavity is divided into two nasal chambers inside that we have a bone so if you have ever touched your nose from inside you you feel a wall in the center and that is a nasal septum that's a nasal septum it is also made up of cartilage what it is made up of cartilage so what we have we have external layers external layers external layers lead to nasal cavity and nasal cavities divided into two chambers two nasal chambers left and the right right left hand right okay all right so the entire nasal chamber is divided into three portion there is first portion where you can also see small hair and in the old age these hairs are very much longer and you can see in your grandfather and mothers these hairs hanging out from the nose right and they also have certain glands known as mucus glands which plants mucus clan so whenever you get you get your nasal cavity inflamed during cold a lot of mucus comes out from this fine so here we have here and here we have mucus gland you all know what is the meaning of mucus gland it's sickly it secretes mucus so this region is known as vestibular region so the first region is vestibular region what is the function of vestibular region to trap the dust particles the work of here and mucus they will clean your air they will trap the dust particle trap the dust particle okay then we have this region this is a respiratory region the function of respiratory region is to humidify the air humidify and condition the air how does it will do now the air enters here so we have done two region one is a vestibular region another is a respiratory region what is present in the respiratory region there are present three pairs of bones one two and three so three bones here three bones on the other side okay so these three bones are known as nasal concave nasal concave so nasal concave what these are bones they are three pairs fine total three pairs three hair three there so these bones are present in a zigzag manner like this just like uh we i we have done in the digestion villi is present so we lie is also kind of a zigzag wherever anything is present in a zigzag manner that means it is increasing the surface area why do we want to increase the surface area because see guys if the bone is present in this manner on the bone it will be present skin that means you have more skin more skin you have now air will have more skin to cool itself you know what happen even if for example if you are present in a very cold area the air is at low temperature the molecules will have less kinetic energy we want molecules to be very you know moving faster because more they have temperature the molecules move faster more will be the diffusion ok for example if i warm if i have warm air in if i and if i have cold air the warm air will diffuse faster because it has high temperature it has the molecules have more kinetic energy they are more active fine so for example if you are living in colder area the air will enter and touch towards the skin of these nasal concave nasal concave bones they have skin on them now this skin will will you know maintain the temperature give a lot of you know humor make a humid environment there and condition the air so whenever i'm talking about conditioning the air that means these that skin will increase the temperature of air it will increase the temperature of it okay and that's important why because more the temperature more the diffusion so they are present in zigzag manner present in zig zag manner why to increase surface area why do we want to increase surface area more the area more air will touch to the skin and there will be more temperature that or more heat will be given to the air fine and this area is the olfactory area or olfactory region why do we need olfactory region very important because without that your food will be tasteless and you will not be able to smell your perfumes right so here we have epithelium known as olfactory epithelium so the main function of this olfactory epithelium is olfection and what do you call olfaction smell right so now this uh your external layer lead to you to the to the nasal cavity divided into two nasal chamber now nasal chamber will lead to the pharynx but again in between them will be present internal layers what will be present internal layers there will be opening after this and this opening will lead to the pharynx that we have done in the digestion pharynx is a common chamber for food and air which will lead to the larynx and larynx to the trachea let's see how does it happen so you have seen this is the larynx if this is the larynx larynx lead to a pipe known as trachea trachea is covered by incomplete cartilaginous drink or c-shape cartilaginous rings known as tracheal rings they are 16 to 20 in number and made up of hyaline cartilage cartilage hyaline so the entire length of trachea is 12 centimeter this is trachea right and what are these these are tracheal rings tracheal rings how many are there 16 to 20 in number and what are they made up of they are made up of hyaline cartilage they are made up of hyaline cartilage fine guys now what is the purpose of them they are c-shaped they are incomplete dorsally that means if this is a ventral side this is the dorsal side they will be present like this so for example this is trachea this is the ventral side this is the dorsal side and they're present like this do i have ring on the dorsal side no so i will say they are c-shaped and they are incomplete or sleek if it would be like this it would be then complete right so we say they are incomplete dorsally they are incomplete dorsally they are c-shaped they are three-shaped what's the function they prevent collapse because air is entering and leaving that may lead to the collapse of the trachea so to prevent the collapse it will give a firm uh you know firm like nature to the trachea and trachea will not collapse at all this track here at the fifth thoracic vertebrae will divide into bronchi imagine this is a place where your fifth thoracic vertebra are present what is a thoracic vertebra guys have you heard of vertebral column your backbone the vertebral column this vertebral column is made up of small bones and these bones they are known as vertebrae your entire backbone is made up of small small bones so the bones these bones are known as vertebrae and the one which are present in the thorax region you call it as thoracic vertebrae fine so where your fifth thoracic tuber is present the trachea bifurcate into true and you call it as primary bronchi what do you call it as primary bronchi so this primary bronchi will further divide into secondary bronchi what it will divide into secondary bronchi just like that it will form a respiratory tree a tree with a lot of branches so they will keep on branching and they will form other structure like secondary bronchi will open into tertiary bronchi and tertiary bronchi will open into initial bronchioles right so we say that your tracheal rings are present right from trachea up to initial bronchial so remember guys your these tracheal rings brachial rings are not just present in the trachea we assume they're present in the trachea only but no the tracheal rings are present from trachea up to initial bronchioles initial bronchials all right okay so now what will happen next the respiratory tree will keep on branching after initial bronchioles what will be formed after initial bronchioles terminal bronchioles will be formed and then respiratory bronchiole okay i'll continue here only i'll continue here only after initial bronchiole what will be form terminal bronchiole after terminal bronchiole will come the respiratory bronchiole after respiratory bronchiole after respiratory bronchiole will come alveolar duct after alveolar duct will be present atria after atria will be present alveoli or alveolar sucks right so this is the entire route so you can see in this diagram you can divide the entire respiratory tree into two portion one is a conducting zone another is a respiratory zone your respiratory zone starts from respiratory bronchioles and it ends to alveoli it tends to alveoli why do you call it as respiratory zone because this is a place where actually exchange of gases takes place so here exchange of gases takes place exchange of gases takes place whereas the conducting zone it starts from your nose it ends up to terminal bronchioles so it starts from nose to terminal bronchiole so its only function is to conduct the air that means it's a passage for passing of the air air is coming from this one so the only thing that it can do is it can condition the air it can humidify the air it can clean the air it can warm the air fine only these things can be done by the conducting zone so what does conducting zone do bomb humidify and clean the air but it will not lead to the exchange of gases this is a portion which where no exchange of gases takes place you call it as an atomic dead space so you also call it as guys anatomic dead space anatomic dead space that means here no exchange of gases takes place no exchange of gases takes place no exchange of gases takes place fine that's a quite difference but in this this is a question that was asked in the exam on sunday so which portion leads to the they gave all the functions of the conducting zone and they asked which of the which of the following function was not performed by the conducting zone then you will say the uh exchange of gases okay all right or the diffusion of gases then we have lungs so all these respiratory tree they're present in the structure for example if i say this is a trachea trachea divide into primary bronchi now this primary bronchi enter into these structures known as lungs known as lungs okay all right so the respiratory entire respiratory tree is present in your the entire respiratory tree is present in your yes inside the lungs so this is the right lung as you can see right lung is broader and shorter left lung is longer and a little thinner right so this one is your left lung and this one is your right lung so the right rung is little broader and heavier and little upside why because here you have liver so due to presence of the liver here right lung is little on the upper side and this one is longer and it has this structure known as cardiac notes in it what is this cardiac notes while you were an embryo and you were developing the heart starts to accommodate and side by side lungs were developing and we say that heart is present little on the left side so due to presence of the heart the lung shape gets deformity or the lungs uh gets a little change in the shape it's not a deformity deform it is a wrong word to say here so because of presence of the heart here the little uh you know shape is formed on the left lung you call it as cardiac note and the center space between the two lung where heart is present you call this space as mediastinum space media steinum space because the lung left lung is little thinner and smaller than the right one so it is divided into two lobes only how many lobes two lobes this is the oblique fissure fissure is anything that divides something externally so due to presence of this fissure your lung is divided into two lobe there is upper lobe you call it as superior loop and then you have inferior lobe the entire lung is divided into left lung is divided into two portion inferior and superior loop due to presence of the fissure now we have this right lung which is divided into two portion so we have two fissures here one we have horizontal figure and then we have oblique fissure as a result the lung is divided into two portion superior lobes the middle lobe and inferior lobe all right now the space present inside the lung where you uh where your air enters you call that space as pulmonary cavity right so for example uh you have the alveoli structures in them we'll be talking about that in detail so these alveoli have a space in them that is a pulmonary cavity so the space present so there are different kinds of cavities guys okay so there are three cavities in your lung one is your thoracic cavity that we have already talked about another is pulmonary cavity that is present inside lungs in the lungs and the last we have is a pleural cavity now what is this so your lungs they are protected by double layer bag like structure you call it as pleura so your entire lung is having this double membrane bag like structure on it so i'm drawing on the one lung it's present in the both okay okay just let me draw here also otherwise we'll get confused okay so here we have double membrane bag like structure this is single membrane this is the second membrane like this okay a double membrane bag like structure you call it as pleura what do you call it as pleura so pleura is made up of two layers it's basically a peritoneum this is what plural so pleura is made up of two layers it is made up of two layer the pink one is visceral layer and this one sorry the green one is a visceral layer all right green one is a visible layer because it is present near the visceral organ and this one is a parietal layer and together these layer they are collectingly form forming the pleura the double back like structure double membrane back like structure what's the function of the plural inside the pleura is present in space you call it as plural cavity what is this guy's plural cavity and plural cavity have a fluid you heard it right it have a fluid and this is plural fluid this pleural fluid performs a very important function first of all shock absorption and second it reduces friction so in a way it is providing protection so the cavity inside that is a plural cavity so the cavity inside the lung is a pulmonary this is plural and the one is where lungs are present is the thoracic cavity fine okay let's talk about alveoli now alveoli or alveolar sags alveoli or alveolar sacs they are total 300 million in us yes 300 million so much surface area so there is more surface area for exchange of gases for what exchange of gases they are highly vascular they are highly vascular structure highly vascular means you will find a lot of blood vessel you will find number of blood vessels a lot of blood vessels okay let's see this one so if this is the alveoli this is the alveoli the cell will i have the epithelium known as simple squamous epithelium what is this epithelium simple squamous epithelium so air sacs or the alveoli they have which epithelium simple squamous so it has certain specialized cells in them so the first type of these cells are simple squamous okay and this is a lumen of alveoli now apart from that they also have certain different cells so you can find certain cells here one such cells are these type 2 alveolar cell and then we have cells known as dust cells which are macrophages so these are dust cell or macrophages all right and then we have these pink color cell what are these these are type 2 alveolar cell these are very important these cells they secrete a phospholipid so a question of was also there in in this exam of neet exam uh lecithin lecithin is a phospholipid though it was a question from biomolecules but it also have an application here so it secretes a phospholipid which is lesser thin the function of the lesser than is to decrease the surface tension it decreases surface tension this lecithin decreases surface tension and prevents the collapse prevent collapse you know so for example in balloon if you fill the air in the balloon it will expand but if you take out the air from the balloon it will collapse so we have to give something to the balloons that they will not collapse and this is what your lecithin and dracula rings it does okay so tracheal rings prevents the collapse of trachea and the bronchioles whereas here lesser than because they do not have any bronchial those tracheal rings tracheal drinks they end up to initial bronchiole later on anything does not have the bron uh these tracheal rings so that's why we need to have something that will prevent its collapse and that is a lesser than secreted by type 2 alveolus fine guys so let's talk about so let's talk about what are the various bones present around the lungs so lungs they are protected by they are also protected by ribcage they are also protected by ribcage now ribcage is formed by three types of bones one are your thoracic vertebrae second are your ribs and third is sternum okay how it is present for example ventrally sternum is present and dorsally thoracic vertebra are present okay and ribs are present like this literally so this entire structure is your rib cage so this is the sternum these are the ribs and this is the thoracic vertebrae so we say that this is the dorsal side they are present dorsally ventral is present the sternum is present ventrally and ribs are present laterally okay let's solve the question now all statements are correct except during swallowing glottis can be covered by a thin elastic cartilaginous flap called epiglottis a portion of which is the common passage for food and air the lungs are situated in the thoracic chamber which is an anatomically an airtight chamber ribcage is formed by sternum and lumbar vertebra so in the previous class we have done that epiglottis is a cartilaginous fat like structure and that belongs to which part larynx so that's why i have not repeated in this class because we have already done in the digestion part okay so this is a larynx guys yes if you can see here this is the larynx this is the larynx your voice box so this larynx it has an opening known as glottis and this glottis is covered by a flap-like structure elastic flap-like structure known as epiglottis so this is true whenever you eat food this epic lotus closes the glottis so that the food does not enter into your trachea which is also known as wind pipe okay all right so if it accidentally does while you're talking and eating you get cough yes pharynx is a common chamber for food and air true yes it is present in an airtight chamber can you see any air coming out from this one no so thoracic cavity is completely an airtight chamber whereas ribcage is not formed from lumber rather thoracic vertebrae okay so answer to this question will be four next brachii is a straight tube extended up to the mid thoracic cavity which divides at the level off where does that it divides it divides at fifth thoracic vertebra one next the inner pleural membrane is in contact with lung surface body wall alveoli and the bronchi what is the inner pleural membrane inner means it they are talking about the visceral one outer means they're talking about the pleural one so it is in the contact with the lung surface right guys so the one which we have done here the visceral layer the visceral layer is also because it's present on the inside so you call it as an inner pleural membrane and parietal one is present outside towards the body wall so it is the parietal one okay all right so next question match the following gills so where do you find gilts you have to match it gills are present in the fish lungs lungs are present in the aves okay simple diffusion by body surface in the flat worms and cutaneous in the earthworm simple right okay next one dash have a network of tubes to transport atmospheric air within the body amphibia insects eaves and reptiles so we are talking about tracheal tubes or trachea and that's a feature of your cockroach and cockroach is an insect answer is two amphibians respire through lungs gills buckle cavity and even the skin whereas the apes through lungs reptiles through lungs ears have a special ear sacs in their lungs next we have is respiration involving the following step so now we are talking going to talk about our respiration so what are the various steps in our respiration or how does your glucose is breaking down into co2 and water and giving you energy so we have to start it from the start so first of all what will happen you will take in the oxygen and throw out the co2 so first step is ventilation or breathing so what happened in pulmonary breathing or ventilation by which atmospheric aid is drawn in and co2 rich alveolar air is released out next diffusion of gases oxygen and co2 across the alveolar membrane now alveoli will take the oxygen and give it to the blood because i've said alveoli is highly vascular and you call it as exchange of gases and then there will be transport of gases from blood the entire gases will go to the tissues because blood helps in the transport of gases then diffusion will take place between blood and tissue so we say that exchange is taking place at two places exchange of gases takes place of two places one between blood and tissues another between blood and alveolar membrane here also exchange okay next then the cells will pick up the oxygen and give you energy this is what entire chapter contains and this is what we will start to study now okay all right so first of all we'll talk about breathing so entire breathing or pulmonary ventilation takes place in two steps one is you inhale the air another you exhale the hair so inspiration is also known as inhalation what do you do in inhalation we take in the fresh air and in exhalation or expiration what do you do we take out or exhale the bad or foul air fine so how does air moves like blood moves from area of high pressure to the low pressure just like that air also move from area of high pressure to the area of low pressure for example if i if i have in this area high partial pressure of oxygen it will move from high pressure to the low pressure right if i have more partial pressure of air to the outside and less in my body the air will move in first thing is this so air moves air moves from area of high pressure to the air area of low pressure now whenever there is increase in pressure there will be decrease in volume this is what we say boyle's law this these two fundamentals are very much important in inhalation and exhalation yes that's true let's see how so let's talk about it in detail so what happened we say that the movement of air in and out of the lung is carried out by creating a pressure gradient between the lungs and atmosphere so if you want to move the lung you need to agree you need to create a pressure gradient what is a pressure gradient what is the pressure gradient difference in partial pressure or the pressures difference in pressure for example if i say these are the lungs and i want lungs i want lungs to take the air if i want inspiration to occur if i want to take in the air i will make sure my pressure inside the lung should be less so that the atmospheric pressure is more an air will move in how can i decrease the pressure i can decrease the pressure if i increase the volume so i will with my effort i will increase the volume and the pressure will decrease air will move in so what i will do in exhalation in exhalation what i will do i will create more pressure inside the lung how will i create more pressure inside the lung i will with my efforts i will decrease the volume and increase the pressure now atmospheric pressure is low and air will move out this is what we will do in uh breathing so how are we increasing and decreasing the pressure we have to make effort and efforts in our body is made by our muscles so yes muscles are involved in inspiration and expiration now what are these muscles let's see so muscles of breathing this is very important from here the question is asked first question can be asked from this portion about the volumes for example they ask during inhalation the pressure inside decreases true or false true during exhalation the pressure inside the lungs increases true or falls true second question the pulmonary volume during inhalation increases this is also true the pulmonary volume during exhalation it decreases this is also true first type of a question can be asked from this person second type of a question can be from a muscle portion now what are the muscles so imagine this is your ribcage in the ribcage we made sternum we made thoracic vertebrae and we made drips this is what it was yes so there are muscles present in between the ribs and the space in between the ribs is intercostal space the space in between two ribs is known as intercostal space this space is postal space what is intercostal space the space between ribs okay okay let me label this also for you this is ribs this is sternum and this is what it is yes thoracic vertebrae now there are muscles present in between the ribs the name of the muscles is on the basis of how they are positioned some are present towards inner side they are internal intercostal muscles some are present towards outside they are known as external intercostal muscle so here we have a muscle guys listen to me this is for example external intercostal muscle and this is a muscle which is internal intercostal muscle then we have here diaphragm what do we have here diaphragm and diaphragm is also a muscular flap like structure diaphragm is also a muscular fat like structure so the diaphragm muscles they are also important in inhalation so diaphragm or phrenic muscle all right diaphragm and phrenic muscle and external intercostal muscle they both are responsible for normal inhalation or normal inspiration whereas your intercostal muscle and there are certain abdominal muscle and which muscle abdominal muscle okay i will not mark it here otherwise you'll get confused both these muscles are responsible for your forceful exhalation so this muscle is for okay forceful exhalation ma'am forceful do we do forceful exhalation do it this is forceful right now i'm breathing that's normal right so yes we also do forceful exhalation and there are certain abdominal muscles present here these are abdominal muscle they are also responsible for forceful exhalation just put our effort and throw out the air you will yourself feel your abdominal muscles are stretched right so forceful exhalation all right so these are various muscle let's talk about the physiology part now so what happened during inspiration so whenever you are inhaling you inhale by two method one you inhale normally and second you inhale forcefully you inhale forcefully so whenever we are inhaling normally we are contracting two muscle one is external intercostal muscle right whenever for example right now you are inhaling you are ex you are contracting your external intercostal muscle and your diaphragm muscle so what will happen if your external intercostal muscle contract when the external intercostal muscle contract your entire ribcage will move upward and outward you just do it with the forceful also you will see your chest coming out so what this external intercostal muscle does it will raise the sternum okay or entire ribcage so ribcage will move upward and outward upward and outward as a result towards dorsolateral axis like i am doing like this okay so i am raising my chest or my ribcage as a result on the dorsal velcro axis the volume will increase okay so what will happen when they will contract they will move ribcage upward and outward as a result what will happen the volume increases at which axis dies torso ventral axis at this axis your volume will increase and the pressure will decrease and when the pressure decreases air moves in all right this is what we do and the volume and the pressure it changes in all the three cavities thoracic pleural and pulmonary because first of all the chest will expand thoracic cavity will expand then plural cavity will expand then pulmonary cavity will expand and all the volumes are increased in all these three cavities fine and during contraction of the diaphragm what will happen here when they will contract they will for example if this is your thoracic cavity okay this is thoracic cavity this is a diaphragm so when it will contract what will happen it will be pulled downward like this so now you can see here the volume of thoracic cavity and here the volume of thoracic cavity what do you think where is the more volume when the diaphragm contracts so when the diaphragm contract the diaphragm flattens and when the diaphragm flattens there will be increase in volume in anterior posterior this is anterior and this is posterior position always your head is on the anterior position and your foot are on the posterior so it will increase the volume in anterior posterior axis and when this increases what will happen the pressure will decrease and air moves in air moves in fine what about forceful in the forceful one what happened in the forceful kind of inspiration your another muscles contract these muscles are present towards this portion what are these name scalene muscle pectoralis and sternocleidomastoid all these are muscles which are present around your rib cage there are no ketomastoid all these are present around your ribcage so when these muscles contract they will move the ribcage more upward and outward and outward right the ribcage will move more upward and outward fine guys so that's about your inspiration let's talk about the expiration what happened in expiration again expiration is of two type one is your normal like you're doing right now and one is forceful so what happened in this one so whenever you are exhaling normally you are not putting any effort whatever muscles of your inhalation have been contracted whether they are of the forceful or they are of the know of the normal inhalation they will relax and when they relax the entire chamber and the volume of the chamber or ribcage it will move back to its original position as a result the volume decreases and pressure increases right whatever they have done they will come back to their original position so what happened here during normal all muscles relax right as a result there will be decrease in volume increase in pressure air moves out what about the forceful in forceful your internal intercostal muscle and abdominal muscles contract what they will do when it will contract it will do opposite to the external external was putting your ribcage upward and outward it will put inward and downward right rib cage moves inward and downward so when abdominal muscles contract for example the abdominal muscle contract they will push the diaphragm to the upward right they will push diaphragm upward what will happen the volume decreases pressure increases same here volume decreases pressure increases air moves out air moves out very simple good to go right so this is how you breathe guys so questions are generally asked from which muscle will contract during which mechanism inhalation or exhalation and what will happen to the volumes and the pressures fine okay moving further on and average a healthy human breathe around 12 to 16 times per minute the volume of air involved in breathing movements can be estimated by using the spirometer which helps in clinical assessment of pulmonary function so we say that how many times do we breathe in a minute 12 to 16 times right and can we measure the breath the volumes definitely we can and we can do it with the help of this machine you call it a spirometer and spirometer was very much important in uh or during the time of covet yes it was really important you know spirometers is inbuilt in the icu machines ventilator machines which can check what is your pulmonary volumes and capacities now what are these pulmonary volumes the amount of air you take in and take out and that's a pulmonary volumes and capacity now what are these pulmonary volumes volumes and capacity capacity is always the sum of volumes it's the sum of volume so it's just about the quantities how much are you taking in and taking out we are talking about numbers now first of all guys we have a volume known as a tidal volume what does tidal volume says tidal volume says it's the amount of air you take in and take out normally when you're not putting any effort right now you're doing that same you're just normally inhaling 500 ml of air and you're also exhaling 500 ml of hair that's it right so what is the toilet volume the amount of air in or out normally its volume is its or its quantity is around 500 ml right this is really important the questions are asked from this portion now second what if what if i put some effort and i put effort and i do forceful inspiration so during forceful inspiration i am taking for example i did forceful inhalation like you also do it with me so this time guys you are taking 500 ml tidal volume inside your lungs and you are also taking some extra amount of air and that extra amount of air or additional amount of air is your inspiratory reserve volume so what is inspiratory reserve volume it's the additional additional or extra amount of air taken in during forceful inhalation during forceful inhalation and what's its quantity 2500 ml to 3000 ml now i said during forceful inhalation i am taking tidal volume also an inspiratory reserve volume also so what total amount i am taking i have to sum up these two and you call it as inspiratory capacity so if i do the total of these two it will become inspiratory capacity inspiratory capacity is the total volume of fear i am taking in during forceful inhalation extra or additional amount of air taking in during forceful inhalation is irv inspiratory reserve volume and what is ic ic inspiratory capacity is tidal volume plus irv what does it says total volume of air taken in during forceful inhalation during forceful inhalation fine now what about expiration we also do forceful expiration isn't it so that is expiratory reserve volume just like during forceful inhalation you take tv and you take you take irv so when i'm exhaling forcefully i'm also exhaling tv the tidal volume and i'm also exhaling some extra amount that extra amount i am exhaling apart from tv is erv expiratory reserve volume what is expiratory reserve volume it's the extra or additional volume of air exhaled during forceful exhalation during forceful exhalation its amount is from 1000 to 1100 ml right so what will be ec expiratory capacity guys what will be ec or expiratory capacity expiratory capacity will be then tidal volume plus erv okay so what does it say total amount of air just like that total volume of air taken in during forceful inhalation and this will be total volume of air taken out during forceful exhalation right this is the capacity now let's talk about one more volume we have tidal volume we have inspiratory reserve volume we have expiratory reserve volume one more volume we have and that is residual volume so all volumes i'm writing it in the green one so what is residual volume whenever you exhale forcefully whenever you exhale out forcefully at that time some amount of air remains in the lung why does it remains in the lung because you always have negative pressure inside the lung a little negative pressure is always maintained so that some amount of air always remain inside the lung and that's residual volume but why we are doing it to prevent the collapse to prevent the collapse of the alveoli right so residual volume is the amount of air remains in the lung even after forceful exhalation even after forceful exhalation okay for example if this is your lung so we say some amount of air always remain in the lung even if you have taken out the erv and even if after you have taken out the tidal volume so whenever you're doing forceful exhalation what goes out of the lung erv and tidal volume what will be remained that amount is residual volume okay now one capacity functional residual capacity okay what's the value of this one 1100 to 1200 ml okay then we have functional residual capacity what is this so when you were exhaling forcefully the air that remains in the lung was your residual volume what if you do not take out erv you only take tv if i'm saying the person is only taking out tv not erv that means a person is exhaling normally this is what i say now if i say there is a person who is not taking out the erv from the lungs but only tv from the lungs how the person is exhaling normally so amount of air that remains in the lungs after normal exhalation if frc functional residual capacity what is functional residual capacity total volume of air remains in the lung after normal expiration now what's the difference between the two what's the difference both are the one which remains in the lung the difference is in the forceful and normal expiration okay now one more capacity that we have is vital capacity what's a vital capacity so vital capacity is formed by the addition of these three tv inspiratory reserve volume and expiration volume for example if i say there is a person there is a person this person is inhaling forcefully this person is also exhaling forcefully so what this person is taking in and taking out during inhaling forcefully this is taking tidal volume plus irv and during forceful exhalation it is also taking tidal volume and erv what's the common tidal volume is common so we say that vital capacity is formed by the union of three things vital capacity is formed by the union of three things one is irv another is tidal volume and whenever i am saying tidal volume i am taking both in and out i am writing both in and out okay plus erv okay now another type another is total lung capacity what does total lung capacity says for example a person inhaled forcefully inhale forcefully when a person inhales forcefully in inside the lungs person already have residual volume and already have erv so while a person is inhaling forcefully what it will take inside tidal volume and irv so this if i total them up this will become tlc total lung capacity which is formed by the union of irv plus dv plus erv plus rv or i can also write it like that vital capacity plus rp because this is vital capacity okay what is vital capacity both times you are inhaling and exhaling forcefully so at that time you will also get irv you also get ev erv and you will also get tidal volume whereas in the total lung capacity so whenever you are inhaling forcefully at that time what is present inside your lungs is a total lung capacity so you know what kind of questions can be asked this is quite important first they can ask you about capacities and what they are made up of like dlc is made up of is equal to this second definition based question third the quantity quantity base like i have already told you residual volume is this much erv is this much irv is this much and tidal volume is this much so these volumes they are also very important okay so let's all question for more clarity guys during inspiration the volume of okay so before starting the question let me explain you one more topic and that is pulmonary minute ventilation minute ventilation what is minute ventilation we say that how much amount of air you have breath or how much ventilation you have done in one minute how much ventilation or breathing you have done in one minute is minute ventilation and this has a formula that's the number of breaths per minute into tidal volume so what is minute ventilation the amount of air inhale or exhale in one minute amount of air in or out in one minute so how much breath are there 12 to 16 multiply it with 500 what will be the answer yes what will be the answer if you multiply it with the 500 yes guys what will be the answer just do it with upper or the lower limit any one it will be approximately 6 liter per minute approximately 6 liter per minute or 6000 ml per minute fine so let's now do the questions during inspiration the volume of thoracic cavity increase because of so it is saying whenever you are inhaling we say the volume increases why does volume increases now you have to tell the muscles okay contraction of diaphragm and external intercostal muscle very true uh okay next relaxation of diaphragm diaphragm does not relax contraction of diaphragm and relaxation of no always contraction of muscle leads to the change in the volumes relaxation no so answer to this question will be one okay you can read it you can pause and then you can read the question nicely next additional volume of air a person can inspire by a forceful inspiration it is saying the person is forcefully inspiring at that time what extra additional volume of where that person is taking what do you call it as you call it as irv if it would be expiration then it would be erv answer is one okay so this is a one type of a question next read the following statement and find the incorrect one conducting part is a site of actual diffusion of oxygen and co2 between blood and atmosphere no that's the part or the function of respiratory portion second the trachea primary secondary and tertiary bronchi initial bronchioles are supported by incomplete cartilaginous ring very true because here from trachea to initial bronchioles we have cartilage in a string and they are incomplete they are not complete the movement of air into and out of the lung is carried out by creating a pressure gradient between the lung and atmosphere yes you have to create a difference in pressure the volume of air involves in breathing movement can be estimated by using spirometer this is also true so we have to find the incorrect one answer is one next match the following columns again second type of a question on the basis of amount irv maximum is irv erv is the 1000 to 1100 rv is around 1200 and tv is 500 okay next a healthy man can inspire or expire exp approximately dash amount of air per minute we have just done it now six thousand to eight thousand liter ml per minute or six liter to eight thousand liter if we take upper limit and lower limits both how does it come if i take 12 it will be six liter if i take the amount of 16 then it will be 16 breath then it will be 8 liter answer is 3 next next we have the very important topic that is exchange of gases exchange of gases how does the exchange of gases takes place first of all the question is where does the exchange of gases takes place first the exchange of gases takes place between alveoli and blood vessel second take place between blood vessel and tissues so this is the most common question asked tell the two places where exchange of gases takes place one between alveoli and blood vessel second between blood vessel and the tissues okay all right now what are the factors that will lead to the exchange of gases exchange means taking in the oxygen giving the co2 and vice versa there are certain factors which are very much important for the exchange of gases the first is partial pressure or the difference in the pressure first is a pressure gradient so earlier when we were doing breathing we were talking about pressure of air right now we are talking about gases now we will talk about partial pressure what's the difference for example i have this amount of thing this is air so for air i'll be always using pressure p but this air is made up of oxygen co2 and other gases so the pressure of individual gas in a mixture of gases is a partial pressure so if i say this is partial pressure so what is the partial pressure pressure of individual gas pressure of individual gas in the mixture of gases in the mixture of gases right so first factor that affects these effectors that affects the exchange of gases first is a pressure gradient so we say more the difference in the partial pressure more the exchange for example if i say in air the partial pressure of oxygen is around 159 mm of mercury and in the alveoli it is 104 there is so much difference yes there is so much difference this is high pressure this is low pressure so air can easily move it can move in right if i say any other pressure partial pressure of oxygen is 159 mm of mercury in alveolitis 104 so here you can see the partial pressure of oxygen is less than alveoli so from here it can easily move inside so more the difference more the more the difference more the exchange of gases exchange of right all right moving further so the one factor is change in the pressure gradient let's talk about the other factor second factor is solubility second factor is solubility so if i say one gas have more solubility than the other so one case which have more solubility can easily pass can easily pass through the membranes and it can easily you can say get exchange so more the solubility more the solubility more the exchange so as we say co2 have 20 times more solubility than oxygen so it can easily be exchanged than oxygen fine third factor is thickness of the diffusion membrane thickness of diffusion membrane now what is this diffusion membrane let's see so we say that if this is the alveoli if this is the alveoli this is the simple squamous epithelium of alveoli and this is the lumen and as you know every epithelial cell have connective tissue with them so this is the simple squamous epithelium of what alveoli below that will be present a basement membrane as every epithelium is incomplete without that so here will be the basement membrane and then it will be surrounded by blood vessels so as you also know the blood vessels or the capillaries they also have epithelium in them and that is a simple squamous epithelium generally known as endothelium so whenever oxygen whenever oxygen has to enter from alveolar lumen to the blood vessel it has to diffuse through all these three membrane what are these membranes first membrane is your simple squamous second is the basement membrane basement membrane and third is endothelium what is this endothelium endothelium is a simple squamous endothelium is a simple squamous of your blood vessel so simple squamous of blood vessels okay so these three layers form your diffusion membrane so more the thickness more time it will take for the gases to get exchange so we say that less the thickness more the exchange less the thickness more the exchange okay now let's move further and talk about the actual exchange of gases so how does exchange of gases takes place all right guys so you must have seen this diagram in ncrt this is the alveoli and this is your heart first of all to understand this you need to understand the circulatory system what yes you heard it right so your heart is four chambered heart is four chambered fine so in this four chambered heart you can see if this is the right side of the heart this is right atrium this is the left atrium this will be the right ventricle this will be the left ventricle fine so we say that from lungs listen to me very carefully okay so we say that from lungs the oxygenated blood enters in the left atrium right and from left ventricle through iota this blood goes to the tissues so that it can give the oxygen so that it can give the oxygen this is what we study right imagine this is the tissues or these are the tissues tissues need oxygen and they will give its carbon dioxide why tissues are doing these because these are your body tissues your cells which are doing oxidation what are they doing oxidation fine so we say that from alveoli the oxygenated blood it enters here through pulmonary vein this is pulmonary vein and the blood and pulmonary vein is oxygenated this is an exception veins carries deoxygenated blood but there is one exception here pulmonary vein carries or the oxygenated blood otherwise veins carries deoxygenated blood i think i said oxygenated earlier so pardon me so well we say veins carries the oxygenated blood but this is an exception pulmonary vein carries oxygenated blood and this is systemic arteries systemic arteries and systemic arteries gives blood to the tissues let me put down the arrows for for more clearance so here the blood is moving like this to the atrium then ventricle then from here to the tissues all right now once this blood once this blood had given the oxygen okay because it is carrying the oxygen it will give oxygen to the tissues and pick up the co2 once it has picked up the co2 so the blood will become deoxygenated and it will enter it will enter into the systemic veins which means guys systemic veins okay so here we have systemic veins and we say systemic veins carries the oxygenated blood so here the deoxygenated blood will now enter into the right atrium from right atrium it will end to enter into the right ventricle from right ventricle the pulmonary artery which artery guys pulmonary artery will enter into the alveoli so that it can pick up the oxygen because the blood is deoxygenated so this is pulmonary artery this is this is pulmonary artery so this is also an exception that pulmonary artery arteries carries we say arteries carries oxygenated blood but this is an exception this one carries deoxygenated blood this is how circulation is so let's see how the exchange of gases takes place now you got to know this oxygenated bed will give oxygen to the tissues and pick up co2 and this one will give co2 to the alveoli and pick ups the oxygen this is how this blood is oxygenated fine so now we say that here all the partial pressures are partial pressures are written we say that in the atmosphere the partial pressure of oxygen is 159 mm of mercury whereas the partial pressure of co2 is 0.3 mm of mercury and you all know the exchange of gases takes place it based on only one phenomenon and what is that the change or the difference in the partial pressure or the pressure gradient so the pressure gradient will lead to the exchange of gases fine so here we say that guys see very carefully the partial pressure of oxygen this is alveoli guys the partial pressure of oxygen in the alveoli is one or four the units will be same mm of mercury whereas the partial pressure of co2 will be 40 okay now the blood which is coming here what is that blood the blood that is coming here is deoxygenated that is in the pulmonary artery so we say that deoxygenated blood is present in one in the pulmonary artery and in the systemic vein so this blood have the partial pressure you can see here it has oxygen in the level of 40 and co2 with the level of 45 mm of mercury okay this is the partial pressure of oxygen and co2 so this blood is entirely same have same concentration of oxygen or the same partial pressure of oxygen and co2 so if i say the partial pressure of oxygen the partial pressure of oxygen is 40 and partial pressure of co2 is 45 let's compare oxygen first here oxygen is 40 here oxygen is one of four now what do you think how does exchange will take place because oxygen is at higher pressure this is at lower pressure so this blood have 40 oxygen and i will have one or four so now it will lead to the movement of oxygen into the blood same in this blood the partial pressure of co2 is 45 whereas the partial pressure of co2 in the alveolar is 40 if i say 45 partial pressure of co2 is here okay and here it is 40 now it will lead to the exchange of co2 co2 will move in the alkali same will take place between alveoli and the atmosphere this is in the atmosphere okay in the atmosphere the partial pressure of co2 is 0.3 and here the partial pressure of co2 is 40 high pressure low pressure co2 will move out here partial pressure of oxygen is 159 here 104 here oxygen will move in similarly now the blood has become oxygenated because it has picked up the oxygen reason because partial pressure of oxygen in the deoxygenated blood was 40 and in alveoli it was 104 so oxygen enters here now in the pulmonary vein and systemic artery we have same condition they have oxygenated blood so the partial pressure of oxygen as it is also written there is 95 mm of mercury and partial pressure of co2 is 40 mm of mercury okay now in the systemic arteries guys as you can see here partial pressure is 95 for oxygen and 44 co2 let's talk about tissues in tissue the partial pressure of oxygen is 40 and partial pressure of co2 is 45 let's compare now here you can see guys that that this is 95 and this is 40 high pressure low pressure what do you think where should the oxygen will move it will move inside the tissues now here co2 is 45 and here co2 is 40 now where does the the co2 will move co2 will move here inside the blood so this is how just on the basis of difference in the partial pressure the gases are moving just from high to low you just need to know the values here you just need to know the values here and everything will go smoothly and you need to understand the type of circulation the gases will always move from high pressure to low pressure okay all right let's move further and talk about the transport of gases so this was about how the gases exchange take place like we said uh here exchange take place at two position one between blood vessel and alveoli another between tissues and the blood this is what it happened but how does this this entire transport of oxygen is taking place or how does the entire transport of co2 taking place we have to see that okay so for that you need to understand what are the two important gases one is the oxygen one is the oxygen and second is the co2 second is your co2 if i talk about how does they get transported how does it get transported oxygen 97 of oxygen is uh is getting transported with hemoglobin how does with hemoglobin if you know the structure of hemoglobin i am writing it in short form hb it consists of two part one is heme another is globin globin is made up of amino acid whereas heme part it contains iron it contains iron right it contains iron so we say that one hemoglobin one hemoglobin contains four iron and one iron binds to one iron binds to one molecule of oxygen that means o2 i'm not talking about nascent oxygen o2 right so here four iron can bind to four oxygen so we say in one hemoglobin for oxygen can easily get transported so when it binds with the hemoglobin it binds to which part of the hemoglobin guys to the heme part and it leads to the oxidation of iron it leads to the oxidation of iron when oxygen binds to iron it gets it undergoes oxidation so we say that here hemoglobin bind to oxygen in the reversible process this is the reversible one and form oxyhemoglobin so 90 percent part of hemoglo 97 percent part of oxygen uh transport with the help of binding state with the hemoglobin what for the rest three person the three percent is transported in the dissolved form in plasma dissolved form in plasma dissolved form in plasma fine okay so let's talk about co2 in a later sections first let's talk about uh the oxygen more now if i say if a person is having 15 gram of hemoglobin per 100 ml of blood this is what we say that that a person who is healthy have around 12 to 15 gram of hemoglobin in male it is always around 14 to 15. in female it is less because female undergo menstruation so we say that in a healthy person 15 gram of hemoglobin is present per 100 ml of our blood okay now if i say 15 gram of hemoglobin is present in 100 ml of a blood and one and one gram of hemoglobin can carry around 1.34 ml of oxygen then how much 15 gram of hemoglobin will carry oxygen if i say one gram of hemoglobin can carry 1.34 ml of oxygen then what 15 gram will carry 15 into 1.35 ml of oxygen which is approximately 20 ml of oxygen but how much blood 100 ml of oxygenated blood why now i am talking about oxygenated blood here i have written only blood because now i am saying the 15 gram of hemoglobin is completely saturated with oxygen so that means the blood will be oxygenated if i say all the molecules of hemoglobin in the blood are having oxygen so definitely the partial pressure of oxygen is higher so the blood will be oxygenated okay now out of this guys listen to me very carefully out of this 20 ml out of this 20 ml right out of this 20 ml whenever you are doing rest because you don't need much oxygen your tissues does not need much oxygen 5 ml oxygen goes to tissues goes to tissues and 15 ml oxygen goes to blood whereas when you're doing certain exercise or you are doing something external strains exercise or you are working or you are in active physiological condition 15 ml of oxygen goes to tissues and five mn two blood if you don't get it let me let me uh give you an idea okay so we did this right we made this diagram this one so in this diagram i said that systemic arteries carries oxygenated right fine what if i say what if i say that the blood that is coming here definitely is oxygenated blood and it carries 20 ml oxygen per 100 ml of oxygenated blood is this wrong or right if i say this blood is carrying 20 ml of oxygen per 100 ml of its sample it's very true fine and i say if this person is in the rest condition the tissues of this person are not metabolically much active these are tissues so at this time this person will deliver how many oxygen 5 ml of oxygen to the tissues and 15 ml will go straight that's the part of deoxygenated blood but same if i say the person is highly active exercising now tissues will get 15 ml of oxygen and 5 ml will go to the the oxygenated black this is what we say fine okay so this is how the oxygen transport takes place let's talk about the transport of co2 or carbon dioxide so if i talk about carbon dioxide carbon dioxide seven percent like in oxygen three percent of the oxygen was transporting in the form of uh the oxy uh sorry three percent was uh traveling or transporting in the form of dissolved form and plasma here seven percent is transporting in the dissolved form in plasma fine now 20 to 25 percent how much 20 to 25 percent goes uh with the hemoglobin again here when oxygen was binding to hemoglobin it was binding to heme portion so it was known as oxyhemoglobin but when co2 binds to hemoglobin it does not bind to the heme portion it binds to the globin portion so here hemoglobin plus co2 again reversible now this will not be known as carboxy it will be known as carb amino hemoglobin why because this one is binding this one is binding to which portion to the globin portion globin is made up of amino acid now rest 70 percent the maximum part is transported as by carbonate ions now what are these bicarbonate ions let's see so whenever water and co2 combines they will form carbonic acid in the in the presence of the enzyme carbonic anhydrase which enzyme carbonic anhydrase fine whenever co2 and water combines in the presence of enzyme carbonic anhydrase which is present abundantly in rbc in rbc so it will form acid which is carbonic acid now with the help of same enzyme with the help of same enzyme i am writing ca for this enzyme okay with the help of the same enzyme this will dissociate into h positive ions plus bicarbonate ions so this is what bicarbonate ions are and seventy percent of co2 is transported as such fine all right so let's solve this questions guys nearly dash percent of co2 is transported by rbc rbc whereas dash percent of it is carried as bicarbonate ion so by rbc they means hemoglobin so 20 to 25 percent by hemoglobin and 70 as bicarbonate ion so answer is one next every 100 ml of deoxygenated blood delivers approximately dash ml of co2 to the alveoli so if we talk about how much ml of co2 is transported by pulmonary artery to the alveoli per 100 ml of blood i just listened understand this thing this is the line of ncrt that's why i made a question out of it so we say that every 100 ml of this blood gives 4 ml of co2 to the alveoli okay so how much ml 4 l so it's a fact you need to learn this guys some things are factual and we need to learn so that is answer three okay so 4 ml of co2 goes from 100 ml of the deoxygenated blood to the alkali okay all right next factors that affect the diffusion of gases are thickness of diffusion membrane very true it affects solubility of gases very true and partial pressure so answer will be for all of these okay next transport of oxygen now let's talk about something which is very important and that is your oxygen dissociation curve so it's a topic under transport of gases only so that's why i have written here heading and that is oxygen dissociation curve so whenever we have to understand the relationship whenever listen to me because this is a topic where a lot of students get stressed out but i tell you this is a savior and this will uh this is quite easy if you just get clicked in one go right so whenever i want to see the relationship between oxygen its oxygen's partial pressure that means the level of oxygen and the hemoglobin saturation that means how much hemoglobin is carrying the oxygen or if i want to see the relationship between the two for example now you have a thing you have hemoglobin and you have a machine by which you can increase or decrease the level of oxygen so now you are going to see what will happen if i increase the level of oxygen hemoglobin will be saturated but if i decrease the oxygen hemoglobin will be empty so this is what we see in this curve known as oxygen dissociation curve now ma'am you are saying that we are joining hemoglobin with oxygen but why the name of a curve is dissociation because here we are more concerned about dissociation than the association that's why its name is oxygen dissociation curve how you will get to know very shortly so let's make the graph okay all right so sometimes you know zoology people also make scraps so this is your graph very lovely here we have partial pressure of oxygen here we have person saturation of hemoglobin okay now imagine now imagine you have hemoglobins okay so when you increase the partial pressure of oxygen the saturation starts like this and it will end up like this so which type of a curve is formed here s or s shaped or sigmoid curve or sigmoid curve okay so we say that here what does sigmoid wherever the words uh the graph is sigmoid it means that everything you start good that means whenever okay so this is really going really bad let me just make it again okay guys so whenever we say there is a sigmoid curve that means whenever we are increasing the partial pressure of oxygen whenever we are increasing the partial pressure of oxygen the saturation increases we if we increase more partial pressure of oxygen more saturation increases that means more hemoglobin is attached to the oxygen but one time will come the graph becomes stationary because all hemoglobin is saturated with oxygen for example if i say you have 15 gram of hemoglobin you have how much 15 gram of hemoglobin if i increase the concentration of oxygen imagine 5 gram of hemoglobin got saturated now furthermore more 5 gram got saturated and then 15 gram got saturated now the graph will be flat why because the 15 gram of hemoglobin was the maximum amount and entire got saturated fine now here the partial pressure of oxygen as you can see here the hundred percent saturation is there here 50 saturation is there fine wherever the 50 saturation is taking place or at what value of partial pressure at what value of partial pressure the 50 percent saturation of hemoglobin is taking place you call this value for example if this is 25 mm of mercury i will call this value as p50 value what is p50 value i say p50 value is that partial pressure of oxygen where 50 of my hemoglobin is filled with the oxygen 50 of my hemoglobin is saturated with the oxygen okay guys right all right so here you can see the partial pressure is low and saturation is not completely done what do you think where does this happen this happens in your tissues so this is this is the place where in tissues partial pressure of oxygen is less and this type of a graph is formed and this where around 50 percent saturation has taken place is usually in your pulmonary artery okay that means in deoxygenated blood but hundred percent takes place in the oxygenated blood so this will be the place of oxygenated blood so uh if someone said where does this this type of a graft is forming when your blood is deoxygenated and this type of a graft will reach when your blood is highly oxygenated so this is a criteria for oxygenated blood this is a criteria for deoxygenated right fine now this graft can shift towards left and right what will be the difference if i shift my graph to the right side a bit then if i shift my graph to the right side a bit then what will happen my p50 value will increase how let's see see guys imagine imagine i'm shifting my graph okay i am let me raise this for more space you will get this this slide okay don't worry so here if i say my graph move my graph moves to the right side imagine such type of a graph is formed so you can also see that the p50 value has been increased this is the new p50 value now okay similarly my graph may shift to the left side is this possible yes practically possible so this is the left shift so two type of shifts occur one is a left shift another is a right shift the right shift usually occur when there is increase in co2 always remember co2 is like your enemy and oxygen is like your friend okay so left shift will occur whenever there is increase in oxygen okay left shift occur whenever there is a increase in partial pressure of oxygen and right shift occur when there is increase in partial pressure of co2 so this is bad this is good as you can see in this shift the partial the p50 value is less so what does it signifies it signifies imagine this is 10 mm of mercury and imagine this is 50 mm of mercury now you can see in just 10 mm of mercury the entire hemoglobin is saturated that's good for you even less money imagine in 10 rupees you are getting a big packet of chips and second situation in 50 rupees you are getting the same packet of chips what is better for you in 10 rupees you're getting the same packet of chips right so just like that left shift is a good one left shift will allow the readily or fast association of oxygen with the hemoglobin so this is always associated with the left shift is always associated with the formation of oxyhemoglobin and this is a bad one it will make sure that your that your what your hemoglobin should not bind with the oxygen so this is always related with dissociation of oxyhemoglobin dissociation of oxyhemoglobin and this is always related with association of oxyhemoglobin or the formation of oxyhemoglobin okay now what are the factors that causes right shift let's talk about them first increase in partial pressure of co2 increase in h-positive ion decrease in ph increase in temperature or increase in bpg whereas the left shift occurs whenever there is decrease in partial pressure of co2 increase in partial pressure of oxygen then there is decrease in h-positive ions just opposite to that increase in ph decrease in temperature and decrease in bpg so this will lead to the left shift left shift is usually or this type of a graph is usually formed when you are talking about the oxygen and hemoglobin saturation near the alveoli because there the partial pressure of oxygen is more and there is more association of hemoglobin okay and this one occurs in the tissue right shift you can see near the tissues okay for example this is the normal sigmoid curve you can see when you go near the tissues these this curve will start to shift towards the right and near the alveolar you will see the association of hemoglobin in the alveolar you see the association of hemoglobin and you will get the left shift there and here in tissues you will get to see the dissociation of the oxyhemoglobin that's why if oxyhemoglobin will break only then the oxygen will get to the tissues right for example if i say in this diagram in this diagram the hemoglobin is coming in the form of oxyhemoglobin if this get dissociate dissociated only then the oxygen will enter here now if hemoglobin will not leave the oxygen how will it will enter inside the tissues now how does hemoglobin leave the oxygen will see it shortly okay now so this is oxygen dissociation curve now why do co2 h-positive ions they are causing the dissociation of oxyhemoglobin let's see so whenever there is increase in co2 co2 will react with water and it will form h2co3 and hence h positive ion and xco3 negative i so that is directly proportional whenever you will get more partial pressure of co2 h positive ion will directly increase why because it will react with this in react these molecules co2 and water will react and form h positive ion so as a result these h positive ions these are enemies of oxyhemoglobin so when these h positive ion they see or see oxyhemoglobin anywhere they will bind to it and they will say no this is my friend you go alone this is my friend you go alone you go alone this is what happens here this is what happens here when the oxygenated blood is going or coming towards the tissues when the oxygenated blood is coming towards the tissues this is the criteria that means what is happening here hbo2 is coming here but when at this point when at this point we saw that there is increase in co2 concentration when we see there is more co2 concentration co2 will form h positive and h positive ion will lead to the breakage of the oxyhemoglobin as a result hbh will be formed here and oxygen will be released this is what happens near the tissues okay that's why it causes right shift now what about temperature whenever there is increase in temperature whenever there is increase in temperature the globin structure gets destroyed globin that means globin of hemoglobin it will get destroyed if it gets destroyed will the entire structure will be intact no if the entire structure is not intact how will oxygen bind with the hemoglobin so that will lead to dissociation so more the temperature globin structure will be destroyed if this structure is destroyed guys what will happen imagine this structure is completely destroyed hemoglobin will not bind to oxygen same with the bpg bpg is by phosphoglycerate by phosphoglycerate or diphosphoglycerate okay by phosphoglycerate or diphosphoglycerate this is a uh intermediate in the glycolysis you know what is glycolysis breakdown of glucose so see in the middle of that bpg or dpg diphosphor two three two three bpg or two three dpg die or by same now so that is formed right sometimes i speak hindi also so by phosphoglycerate is formed and when its concentration is more it also destroys the structure of hemoglobin this destroys the structure of hemoglobin so this is how it will lead to dissociation of hemoglobin with the oxygen all right guys that's about the shifts let's talk about the transport at two places how does the transport take place imagine now you will say ma'am you always say imagine now after some time you started saying imagine okay anything nothing is possible without your imagination so this is tissues right and this is your blood vessel what do we have in blood vessel rbc rbc okay now imagine the blood that is coming here the blood that is coming here is oxygenated which blood oxygenated blood just the way we have done here guys just the way we have done here i'm just talking about this portion again i'm talking about this portion again okay don't worry so here in tissues because oxidation is uh taking place so there will be more production of co2 it is producing co2 now this co2 7 will be dissolved in plasma right around 23 percent will bind with the hemoglobin and form carbaminohemoglobin and seventy percent how much percent seventy percent will react with water and form carbonic acid and hence hco3 negative plus h positive i this is what we have done here also this is the what we have done here also just look at it hurry up now because this blood is oxygenated blood so the oxygen is already saturated with the hemoglobin but when this blood reaches the tissue tissue is producing a lot of co2 so co2 will produce h positive iron and this such positive ion cannot bear these two love birds together hb and o2 so this h-positive i this h-positive ion what will they do they will bind with this one causes the dissociation of oxygen and oxygen will lead to or go to the tissues so what's basically happening here we are saying at this position there is increase in partial pressure of co2 the more co2 you will produce it will lead to the more dissociation of oxyhemoglobin hence it is leading to the transport of oxygen or unloading of oxygen imagine hemoglobin was a truck and this truck was was loaded with oxygen now it has came to the site where we need construction okay for example this this oxygen is your sand or bricks and hemoglobin is truck and this is a site of construction so now uh this truck is taking the oxygen right or this truck is taking the bricks now when h-positive iron came when a sponsor iron came what is h positive n imagine these are something for example you you are unloading the bricks here and you're picking up the cement from here so now h positive ionis cement and oxygen was a brick so you are unloading the bricks and you are loading the cement now this is what we are doing okay so by increasing partial pressure of co2 it leads to unloading and transport of oxygen this effect is known as boher's effect what do you call it as boher's effect in bohots you have ona and this leads to the transport of oh oh is effect now this same is going to the alveoli whatever is formed is going to the alveoli in alveoli the partial pressure of oxygen is more okay and this is the endothelium and this is the rbc this rbc is coming and it is a part of deoxygenated blood okay now what will happen what have we produced here one thing we have produced here is h b co2 hb co2 this is one thing we have produced another thing we have produced in this one is hbh these two things we have produced and we are bringing this in the rbc as these forms now when h positive ion is formed here what about hco3 negative hc3 negative will move back in the plasma and react with sodium or potassium i and it will act as buffer what does it act as buffer okay now in place of hc3 negative chloride ions enter here and you call this phenomenon as chloride shift what do you call it as chloride shift okay now what will happen when event this rbc which has a lot of carbominohemoglobin and hemoglobin bind with h positive ion when it will enter around the alveoli okay it's moving the blood is moving now we are talking about this portion guys now we are talking about this portion this one this portion okay here we have done we have made hbh and we have made what hb co2 now this blood is moving and it has reached here so here the blood is having hbh and hb co2 how does co2 will move there let's see so what happened because there is increase in partial pressure increase in partial pressure of oxygen due to increase in partial pressure of oxygen here this entire this entire will become hb hbo2 and co2 will be unloaded co2 will be unloaded because now the partial pressure of oxygen is small also because the partial pressure of oxygen is more again the reverse takes place hbo2 will form and h positive ions will be free now because h positive ions are free this hco3 negative hco3 negative will move inside hco3 negative will move inside and chloride ions will move back and this is known as reverse of chloride shift this is known as reverse of chloride shift okay because h positive ion is now free now it's co3 negative is a die hard lover of h positive vine h3 negative though h positive ion already betrayed at co3 negative and bind with the hemoglobin but now so3 negative is a die-hard level so when he saw that edge positive ion is free so hco3 negative will come back again and reverse will take place with the help of same enzyme which is carbonic anhydrase and what will be form guys here what will be formed h2o plus co2 and co2 will go in the alveoli and co2 will go in the alveoli the enzyme will be same that's why we say it's a reversible process so this is how when near the alveoli there is increase in partial pressure of o2 which leads to unloading or transport of co2 you call this effect which is quite opposite to the board's effect is haldane's effect what effect is this guy's valentine's day okay so this is how transport takes place now you must be thinking ma'am so tough nothing is tough if you know how the gases are transported it is easier and if you know near the tissues the partial pressure of co2 is more it is easier just if i know it this is the kind of thing you will not understand in one go what do you have to do rewind it watch it again okay don't worry stay calm don't worry okay all right so this is how the transport of gases takes place guys let's talk about regulation of respiration so there must be something that leads to the you know regulation that can control the respiration before controlling the respiration we have two things one are the centers and other are chemo sensitive areas chemo means chemical these areas are sensitive to chemicals that means they can detect your chemicals they can detect your chemicals first we'll talk about centers centers are main so centers they are of two type one is respiratory rhythm center so centers also known as respiratory centers they are of two type one is respiratory rhythm center and another is a pneumotechic center both these centers as everything is controlled by brain so both these centers they are present in the brain respiratory rhythm center is present in the medulla oblongata and pneumotaxic is present in pawns because the pneumonic there is p so p for pawns right because in exam you will get a written thing nobody is going to speak so there you can see pp pawns otherwise when you speak the p is silent so this one controls normal inspiration normal breathing just like uh now you are doing the breathing now it is only leading it whenever the medulla is giving signal you inspire for certain seconds so when the signal is off from the medulla the muscles will not contract and naturally expiration takes place so signal is always sent for inspiration because in normal inspiration muscles are contracted we always have to send the neural signal when we need to contract the muscle right imagine if i say in normal inspiration two muscles are contracting in normal expiration no muscles contract so when medulla is giving signal to your external intercostal and diaphragm muscle they contract and leads to inhalation imagine that occurs for 0.4 seconds now after 0.4 second the medulla will stop giving signal and naturally the muscles will relax and expiration takes place this is what happens here the pneumotechic center is known as switch off center so you must be thinking it will stop your breathing no switch off doesn't mean stop your breathing it alters the rate of breathing alters the rate of breathing how imagine uh while normally you are you are inhaling imagine you inhale for 0.4 second and you exhale 4.4 second so while you're running your breathing rate gets increased it fasters it gets fast so what happened during at that time you're not taking deep breath you are taking shallow breath for example now you will breathe for point force in spite of point four you will inhale for point two second that's why our breathing is like like that okay but while we are normally inhaling deep breath it's like that here we are inhaling for more duration so altering the rate means more shallow breaths more shallow but more in number breaths okay so this is how it alters the rate in chemosensitive areas we have two types of chemosensitive areas one is central another is peripheral so both these areas they can detect certain chemicals these are key they have chemoreceptors what do they have they have chemoreceptors so these chemoreceptors are present in the brain as well as in the blood vessel so the one which are present in the brain you call them as central chemoreceptors you call them as central chemoreceptors they are present in medulla near this center respiratory rhythm center whereas peripherals they are present in blood vessel like carotid artery and iota you all know what is iota the one that takes away the oxygenated blood from the left ventricle and carotid artery present over here and it supplies blood to the brain right so all these chemo sensitive area they can only detect they can only detect partial pressure of co2 and h positive ion increase in concentration mind it okay so for example in blood vessel imagine in blood vessel there are certain chemoreceptors present here okay now imagine the partial pressure of co2 increases these chemoreceptors can readily detect the increase in partial pressure of co2 or h-positive ion they cannot detect the increase in partial pressure of oxygen first of all they will always detect the increase not the decrease they always detect the things in higher concentration they cannot detect oxygen the reason is because oxygen is present in conjugated form with the hemoglobin 97 is already bound to the hemoglobin free is only three percent and chemo sensitive areas can only detect three percent of the oxygen which is very low or chemo sensitive areas can only detect free gas it cannot detect the gas which is in the bound form so here no oxygen can be detected can be detected it can only detect the partial pressure of co2 and h positive ions fine guys that's about the regulation let's talk about the certain terminologies so whenever we use the word hypoxia what does it means it means decrease in partial pressure of oxygen if i talk about hypercapnia what does it means it means increase in partial pressure of co2 okay so when does hypercapnia takes place when there is no exchange of gases or when does hypoxia takes place when there is no exchange of gases hypoxia can takes place by various factor one such factor can be altitude sickness what is altitude sickness i'll let you know shortly second it can be due to anemia imagine you do not have enough rbcs no rbc no hemoglobin no oxygen right it can also occur due to toxicity imagine some toxin came into your body and it binds to hemoglobin or it destroys hemoglobin it can lead to right so these are certain factors which can lead to hypoxia in your body all right okay let's move further and talk about the disorders now why did i explain you hypoxia because that will be important in disorders all right my dear students first is asthma you must have heard of asthma in english we say as mind hindi we say asthama okay so asthma is difficult in breathing and there is wheezing sound due to inflammation of bronchi and bronchioles what happen in asthma it's basically the allergy or hypersensitivity a person is allergic to dust person is allergic to dust as a result the person's bronchials or bronchi they got inflamed so when these inflame these bronchial bronchioles get inflamed there is narrowing of lumen lumen means the inner space for example you can say this is a normal human so wide right the inner space it can easily lead to the transport of number of gases or large amount of gas but in asthma the person's lumens get narrower like this so less oxygen enters and person uh so bronchi or trachea will start producing sounds wheezing sound like like that okay it's not even like that it's a wheezing very you know sharp sound is like that okay so that leads to difficulty in breathing and a person can even die due to asthma attack that's why that people always carry that pump what is that for that is for dilating the lumen that is for dilating the lumen okay all right next is emphysema emphysema is a chronic disorder chronic means very dreadly in which alveolar walls are damaged due to which respiratory surface is decreased one of the major cause of this is cigarette smoking so you can see this is a lung of a smoker and this is a lung of a normal person so when a person smokes so much the alveoli gets damaged alveoli gets damaged so when alveoli gets damaged the surface area for exchange of gases it decreases and no more gases can enter inside the body and this can be fatal a person can even die due to this disorder that is emphysema so remember this do not affect upper respiratory tract it affects lower respiratory tract that is your alpha lie okay next let's talk about occupational respiratory disorder what are these so occupational respiratory disorder occupation means work place so person works at a place where the person is exposed to certain chemicals every day for example a person is working in the glass factory so person is exposed to silica every day and that leads to silicosis or a person is pre working in a factory where asbestos is formed and person gets uh the disease the person gets a disease asbestosis what is asbestos in many homes you must have seen that green color shed or blue color shed so it's generally they are made for shade or preventing the sun rays entering directly into the house so that is made up of asbestos right so for example a person is working there and cutting that sheet those fibers from the sheet will enter inside the nose that gets into the lungs in the lungs they are present the trachea and bronchi okay now what will happen the wall of the bronchi it contains elastic fiber which fibers elastic fiber imagine these are elastic fibers okay so when these chemicals now let's make chemicals when these chemicals okay what color should i use right when these chemicals enter inside this elastic fibers are destroyed and when these fibers are destroyed you call it as fibrosis which leads to the increase in the thickness when the muscles are destroyed they are no more elastic the thickness of the wall increases the thickness of the wall increases hence narrowing of human the fibrosis that leads to thickening of wall thickening of wall why because earlier the you know this fiber was elastic and it was single now it has been broken down into pieces and no more elastic which will lead to the accumulation of small small parts and hence the inflammation response start and the wall become thick leading to narrowing of the lumen okay so by fibrosis there is thickening of wall occurs you call it as proliferation okay let me just read this for you so when the the thickness increases this narrowing of lumen and a person is not able to breathe this can lead to permanent damage also so that's why people who are working in these industries they should be provided with proper mask and all okay this can also seen in people uh and the diseases black lung disease in the people who work in coal mines in coal mines okay all right so in certain industries especially those involving grinding or stone breaking so much dust is produced that the defense mechanism of the body cannot fully cope with the situation now earlier when you have a one or two exposure with the dust usually you can also go to factory and you get exposed but you will not get a disease the constant exposure will cause a disease why because when they come in a small amount our immune system can easily cope with them and they can destroy them okay but when there is a constant exposure long exposure long exposure give rise to inflammation leading to fibrosis proliferation of the fibrous tissue problemation means growth it will get thickened and thus causes serious lung damage workers in such industry should wear protective masks so people should wear masks that will protect them from that long exposure okay all right so this was about your occupational lung disorder next is pneumonia so pneumonia is a disease that occurs either through a bacteria which is hemophilus or streptococcus okay what what are these bacteria so the bacterias enter through droplet infection what you call it as you're sneezing or coughing so when bacteria enters inside your alveoli obviously a bacteria is entering the mucous cell will secrete a lot of mucus as you can see there is a lot of fluid here fluid in the alveoli we say that in ammonia the fluid the fluid accumulation occurs in case of pneumonia in the alveoli so from where does this fluid come first this fluid is basically the mucus the mucus excess mucus production occurs whenever there is inflammation for example during cold you get infected with virus right and you get a lot of law a lot of runny nose just imagine the same thing occurs inside the alpha line it will lead to accumulation of fluid also this fluid comes from extracellular fluid that means the fluid present outside the tissues because the virus or the bacteria right in case here the bacteria will kill these cells leading to the entry of fluid here so this basically contains extracellular fluid and mucus so whenever there is a fluid is filled in the alveoli this will decrease the surface area for exchange of gases there will be decreased surface area for exchange of gases okay so this is what happened in pneumonia so people who have extreme pneumonia that in fact fingernails and skin can become blue why because a person is because there is no exchange of gases so a person will face hypoxia and hypercapnia and due to hypercapnia what is hypercapnia increase in co2 due to hypercapnia the blood will appear blue right you call it a cyanosis diagnosis is blue blood we always draw now uh the deoxygenated blood is blue and veins are blue because they carry deoxygenated blood because more co2 will give a blue color and whenever we are talking about blue in biology we use the word cyan okay all right next let's talk about carbon monoxide poisoning so what happened in carbon monoxide poisoning though hemoglobin bind to the oxygen and form oxyhemoglobin but when there is you know burning of a fossil fuel imagine there is a room and you burn a fossil fuel there and there is no window no ventilation carbon monoxide will be formed carbon monoxide is formed by burning of fossil fuels so that carbon monoxide is very much poisonous because it has it has affinity towards oxygen around 200 times more it has the affinity towards the hemoglobin than the oxygen around 200 times more see if i say oxygen is binding with hemoglobin their love is okay eternal and so but when co comes and co comes carbon monoxide the hemoglobin and co they have love from generations or money what do you say in hindi janmo janmo kapiar right so co has 200 times more affinity than oxygen so this will bind to and this binds the process is irreversible and now no oxygen can bind hemoglobin is completely saturated and a person will eventually die of suffocation so this happened in carbon monoxide poisoning so wherever there is more pollution there is more carbon monoxide and person usually have these breathing issues or sometimes they feel dizziness more dizziness right wherever there is increase in pollution when i was living in delhi i i know there was a lot of pollution at up at a point of time there was a lot of pollution that i always used to feel dizzy and my eyes are irritating why because my hemoglobin is saturated with carbon monoxide so how how my oxygen is going to be there in the tissues it will be difficult for that okay all right okay so let's talk about mountain sickness what about mountain sickness so whenever you go at high altitude high altitude like in mountains of like uh mount everest or rhodang pass or ladakh region at high altitude there is less partial pressure of oxygen okay imagine earlier at the plane i'm just giving you rough value the partial pressure of oxygen was uh 5 mm of mercury in the atmosphere and in the lung it was zero so how much is the difference five a lot the gases can easily pass imagine at high altitude the this drops to 1 mm of mercury and this is again zero so now tell me how the gases can move no there is a less partial pressure in the gases so whenever there is less partial pressure of oxygen in the atmosphere in atmosphere no or less exchange takes place exchange of gases takes place so that's why whosoever goes to high altitude especially in the dark and so they are advised to rest for one or two days and get acclimatized so what happen when you do not have enough oxygen you will feel nausea a feel of vomiting right you will you know get an extreme headache and sometime it can even lead to fatal condition a person needs oxygen cylinder you can see that person is using okay so that's why i always uh stay for one or two days have rest and then started going for tourism and all right like a tourist so uh so whenever you go to high altitude uh these are the things you face but those people who already are living they get acclimatized acclimatize climatize means adapt it so how does body gets adapted or even after one or two days you your body it will increase the number of rbc it will increase the number of rbc more than rbc more oxygen transport less rbc less oxygen transport if oxygen is less less increase the truck that's it okay so this is your mountain sickness let's talk about decompression sickness so mountain sickness was when you go at high altitude so when you go at low altitude or you go uh in the diving so when you go for diving there is increase in partial pressure of gases increase in partial pressure of gases and which gas i'm talking about here is nitrogen so when a person sees that person has undergone for diving and now he's a feeling decompression sickness so what happened for example this is a surface of water and this is a sea bed this is a sea bed okay now diver goes down so when the driver goes down there is increase in partial pressure of nitrogen earlier the partial pressure of nitrogen was less so that's why the partial pressure of nitrogen was less so that gas was not able to enter inside my body but now the partial pressure of nitrogen has increased down here now nitrogen enters and this will lead to dizziness dizziness right so that's why it is advised not to stay for around more than 45 minutes down in this sea bed even i have done the diving i have seen the corals in more leaves right so it's it's really beautiful but even i was i have suffered some decompression sickness i'll let you know shortly so now when you have to move move up it is always a advice to move in this manner like this in this manner a person should never move up in one goal why because when you move up in one go the nitrogen leaves tissues and it will enter blood and when it will enter blood it forms bubbles it forms bubbles so when a bubble is formed the capillaries got burst capillaries first and this can lead to a lot of disorders you know sometimes the capillaries of this eyes get burst and the eye got serious injuries fine so when you go up you should go in a zigzag manner so these symptoms of dizziness is usually seen by or it can you know it's a common symptom for every diver so when i went for diamond diving and i went up for two days my body was like that i was not able to walk for example you have a fever but you do not have high temperature and you're not able to walk and you're dizzy like your entire body is paining it's aching very much and you do not have you know like in hindi sinha jaani nairathi just like that okay so this is what happened in the diving but it's really beautiful whenever you get get the time and you ha you do not fear of you have no fear of water and you have that courage definitely do it in life it's a you know once in a life thing it's it's worth the shot so the chronic respiratory disorder due to heavy smoking in which the alveolar walls are damaged is asthma bronchitis pneumonia emphysema simple cigarette smoking emphysema so now you must be thinking ma'am have gone to more leaves and for diving and so you know when i was um in my bachelor's and uh our teacher was teaching us about these silly traits in detail so cilian creates you know they uh secrete calcium and they form corals and see she's shown us one that video and i was so much fascinated so i told my professor that one day i'll collect the money and i will definitely go and that was somewhere in my mind one day i will do something i'll do a job and i will collect all the money because you know my parents was not able to afford such kind of a big trip right so and i will definitely go for diving and yes i did and i'm really proud of myself i was so much fearful you know i was not able to jump from that boat but i made it i tell you i made it and once i was inside that water and touching those corals amazing that was amazing i think you should also make some goals in life and fulfill them this is this is what it's all about life is all about this more goals you have more happily you will live and you know you will never get bored of yourself and you will always be doing something always be doing something all right guys next lack of pulmonary surfactant can cause asthma atelectasis cystic fibrosis emphysema so if imagine i don't have surfactant what is sufficient lecithin the effectant is something that decreases surface tension that decreases surface tension if the surface tension uh or i say the surface tension increases or lecithin is less then what will happen collapse and other name for collapse is at electosis this is the another name for collapse right next which of the following is uh occupational lung disorder and thoracis no anthrax is and thoracis only and this occurs to us anthrax to animals and thoracis occurs to us due to bacillus and thoracis okay silicosis is the occupational respiratory disorder what is botulism botulism is a kind of disorder that occurs due to bacterium clostridium botilinum it leads to uh you know paralysis of muscle what do you lean on this is a bacteria okay it causes paralysis of skeletal muscles next okay pneumotex center can moderate the function of the respiratory rhythm center it is present in simple question where is respiratory uh there is pneumotic center present you say to the another line was there just to confuse you so this is what i have also seen in the exam of nate 2022 they have written a lot of lines just to confuse you but you are the tigers and the tigers you do not get confused next high po2 may be that is not visible but this is high partial pressure of oxygen low pco2 lesser edge positive concentration lower temperature it is saying high po2 low pco2 low h positive iron and low temperature so all these causes left shift now read the option favorable for oxygen hemoglobin dissociation and causes right shift no forget all those which have right in them right shift in them okay next favorable for formation of oxyhemoglobin and causes left shift left shift is good and oxygen will bind to hemoglobin answer is three in fourth it is written dissociation of oxyhemoglobin so this is incorrect next the next is thank you so this is all about this chapter i hope you will study it well and read the ncrt also and i'll bring another lecture another chapter and i want you guys to please see dncrt side by side because that's really really really very important and mark all the pyqs and whatever you know booklets or modules you have for practice and i wish you all the very best i'll meet in the next class bye bye take care lots of love