 Good afternoon everyone. Am I audible? Yes. What have we discussed till now? Anyone? What all we have discussed? Tell me please. We were discussing excretory system. Any doubt in that? Is there any doubt in excretory system? No. Anybody else having doubt? We'll be starting in next one minute. Yes. Let's see. Am I audible now? Pranab, can you hear me? Yes. Let's see. We were discussing excretory system. Now some part of endocrine system we are going to discuss now. Let's see. Endocrine system. What do you think? What is endocrine system? Do you people know about the word coordination? Do you people know about the word coordination? Tell me. What is coordination? Yes. What is coordination? Let's see. When we run your skeletal system is used. Muscles are used. Yes or no? But you will observe this thing that even your heart rate increases. Your respiratory rate increases. Yes or no? Everyone? Heart rate, respiratory rate, everything is going to increase. And when we stop, what happens? When we stop, heart rate comes to normal. And respiratory rate also comes to normal. Do you people observe these things? Say yes or no? We are going to observe these things now? Yes. Why it is so? It is because of coordination. Because of coordination. So what is the meaning of coordination? It is the process by which or more. Agreed? It is the process by which to or more organ or organ system. Interact, complement, function of each other. Do you people agree? Do you people agree? I am explaining endocrine system. Agreed? Here is it. I have just explained coordination part in that. Getting one point. Do you know what all systems are there for coordination in your body? We have nervous system and endocrine system in place for coordination. Everyone. Any doubt in that? Yes. The thing is, this will be known as neural control and coordination. And this is known as chemical control and coordination. Everyone. Have you any doubt in this? Do you people have any doubt in this? No? Yes. You will ask me sir, is there any special significance to, you can say for these two systems? Yes. This is point to point. Only going to supply those cells, which are, you can say, which is having the nerve supply. It is like electricity, you can say connection of your house. And it is diffuse. Agreed? Yes. I will say hormones are released into blood and any cell having receptor can use the hormone. Actually try to understand my point. Here is the hormone. And one cell is there. This is the receptor. This hormone will join the receptor to form hormone receptor complex. In that case only what is going to happen? Physiological effect will be there. So this is there. What are other difference? See, the neural coordination is, you can say onset is fast. It happens quick and short lasting. And here the onset is slow and long lasting. Yes or no? These are the major differences that are there. So you people are going to read these topics under coordination. Everyone. Now let's see, what will I say? Over here, endocrine system. Endocrine system. This system is going to have two things. This system is going to have two things. Let's see, it is consisting of endocrine gland hormones. Endocrine gland and hormones. Do you people have any problem in this? Let's see. Gland is there. Gland is having two parts actually. In general, let's see. This is a gland. This is the secretory part of gland. And this is the duct. Duct simply means a pipe. Duct simply means a pipe. Agreed everyone? So endocrine glands are duct less gland. Only secretory part is there. Okay. And its secretion is directly poured into blood. So where the secretion of endocrine gland is going to go, where the secretion of endocrine gland is going to go, it will be poured into blood. And the hormone will circulate through blood only. So this is endocrine gland. People can see. What is the definition of hormone? Can you people tell me? What is the definition of hormone? Anyone? Anyone of you? Do you people know definition of estimulator? Pernab is saying estimulator. See Pernab, actually hormone is not always a estimulator. It can stimulate the function and it can, you can say, decrease the function also. Agreed everyone? Let's see. What will I say over here? The hormones are non-nutrient chemicals secreted in a small amount. Non-nutrient chemicals which is secreted in a small amount. Yes or no? First thing it is, it is non-nutrient chemical. It is not going to provide any kind of nutrition to your body. Everyone agree? Means you are not going to get any energy or something like that from a hormone. Everyone is there in doubt? This was secreted in a small amount and act as intercellular messengers. Means it brings information from one cell and supply it to another cell. Yes or no? Everyone? Yes. So this is there. I will talk about hormones. I will talk over here the classification of hormones. What is the classification of hormones? Please tell me here. Based on chemical nature hormones are of following types. What do you think? First is peptide, polypeptide protein. Rather I will say all protein hormones. Second is amino acid derivative. Yes or no? Have you heard about these things dear? Because I want to make one thing clear. I want to make one thing very clear over here. Amino acid derivative. It can be hydro. It is asteroid in nature. Asteroid is a lipid. Do you people understand? You can say difference. Sir but aren't these no? They are no nutrient thing. They are not going to be metabolized to produce any kind of energy to your body. They are non-nutrient chemicals. Everyone? Do you have any doubt in this? Yes. Let's see. Asteroid hormone. Are you people aware about protein, lipid, carbohydrate and all? So if I am going to write yes. If I am going to write all the hormones are proteins. What will you say? Is this a statement correct or not? This is a wrong statement because I have told you people four classes that is there. What are there in the steroid hormone? Testosterone. Second one is estrogen. Third one is hormones of adrenal cortex reason. Everyone? I will let you know. In Iodothyronein, T3 and T4 is there. Let's see. T3 is there. T4 is there. What is T3? T3 is tri-Iodohyronein. And it is tetra-Iodothyronein. Only T4 is known as thyroxine. You can ask me, sir, which kind of, how this is Iodothyronein? Actually, one amino acid is tyrosine. Do you know about this amino acid? Have you heard the name earlier? At any place, tyrosine. With that, iodine going to be joined to form Iodothyroneins. So can you people see over here for secretion of Iodothyronein? Iodine is needed. Yes or no? Is it needed or not? Yes. Everyone? In amino acid derivative, there are two. What is epinephrine? Nor epinephrine is there. And you can say peptide, polypeptide hormone. Hormones of pituitary gland, hypothalamus, etc. Everyone. Do you people agree with this? Anybody having doubt on these things? Now, what all glands are there? Let's see that. What all glands are there? Yes, tell me, dear. Can you scroll up, sir? What? Scroll up? Yes. Scroll up. Done. Now, what all you can say? Endocrine glands are there. You people can observe a bit. There are three in the head. Let's see. Following are the endocrine glands. Are the endocrine glands? First is pituitary gland. Second is pineal gland. Third is hypothalamus. Fourth is thyroid gland. Fifth is parathyroid gland. Sixth is thymus, pancreas, adrenal gland. And ninth is gonads. In gonads ovaries there and testis is there. I don't know. The question is which of the following is not endocrine gland. Is not endocrine gland. One is pituitary gland. Second is pineal gland. Third is thymus gland. Fourth is salivary gland. What do you think, dear? It is salivary gland. Yes, of course. Then what kind of gland is salivary gland? Tell me. What kind of gland is salivary gland? Anybody? Exocrine. So salivary gland is a exocrine gland. It is a salivary gland. One thing. The next thing is there are few mixed glands also. Pancreas is a mixed gland. Why? It is having pancreas having endocrine as well as exocrine. Both the parts are there. See, this is a typical exocrine gland. Gland with duct. Exocrine glands are gland with duct. Is there any doubt? Tell me, dear. Is there any doubt? No. Understood? Here till now? Just a minute. Yes, everyone. Tell me if you have any doubt. No? No. I will be talking about some of the glands over here. Let's see. Just give me a minute. I am going to show you a diagram over here. I am going to show you a diagram over here. What is the connection between endocrine gland? That is pituitary and hypothalamus. Do you people know? Let's see. I will talk about hypothalamus and pituitary gland. Let's see. Hypothalamus and pituitary gland. Yes or no? Hypothalamus and pituitary gland. Let's see. What happens? This is your hypothalamus. This is your hypothalamus. Everyone, this is infundibulum. It connects hypothalamus to pituitary. Agreed, everyone? Any doubt? What is infundibulum? Can you people explain? It is the connection of hypothalamus to pituitary. Agreed? Now, this is pars, distalus, or anterior lobe of, this is pars nervosa, posterior, and this one is, the red one is pars, intermedia, or intermediate lobe of pituitary or middle lobe of pituitary. Agreed? Everyone? Everyone? Any doubt? Tell me, dear. So how many lobes are there? Yes, of course. Any doubt? Agreed? See. Now, there is one blood vessel. You see. These are the neurons present in hypothalamus. Anybody having any doubt in this? Please see this diagram. New people have to pay attention over here. See over here. Do you know? Do you people know? The hypothalamus is going to control secretion of anterior pituitary and posterior lobe of pituitary. You can say over here. Hypothalamus is going to release a hormone. Over here, this hormone will come inside this blood vessel, will travel through this and will leave from here. And from here, the hormone that is flowing, the hormone that is flowing from hypothalamus pituitary comes. Do you know what this structure is known as? This structure is known as hypophysiol portal vein. Can I say it connects? Can I say it connects hypothalamus to anterior pituitary? Can I say that? The hormone which is flowing from hypothalamus is going to go to pituitary, anterior pituitary via which vein? Hypophysiol portal vein. Yes or no? Everyone, any doubt in this? Tell me here. If I will say over here that hypothalamus is connected to anterior lobe by hypophysiol portal vein, do you people have any problem? Say yes or no. Do you people agree with this statement of mine? Agreed or not? Tell me here. Let's see. Now hormone released by pituitary gland, by pituitary gland. Let's see what is going to be there. I will talk about anterior lobe of pituitary, middle lobe of pituitary and posterior lobe of pituitary. Everyone, anterior lobe of pituitary. Let's see what all hormones are going to be released? Growth hormone. Lutinizing TSH, TSH. It is thyroid stimulating hormone. One is FSH. Collocal stimulating hormone. Next one is ACTH. Adrenal corticotropic hormone. And TRL. Prolactin. Have you heard about these hormones? It is responsible for growth of the body. It is responsible for ovulation. It acts on thyroid gland. It is responsible for development of follicle. Inside female ovary. Done. It acts on adrenal gland. TRL. Prolactin is responsible for what? Synthesis of milk inside mammary gland. What? Synthesis of milk inside mammary gland. Everyone. Milk means milk releasing volum. Tell me, dear, any doubt in this? Do you people agree with all these things? Milk not milk releasing. I have made a mistake over here. It is milk synthesizing rather. It brings about synthesis of milk. Not releasing. For release, some other hormone is there. One is MSH. It is melanocyte. Stimulating. Just give me a minute. Yes, dear. Melanocytes are cells present inside your skin. Melanocytes are cells present in your skin. And it synthesizes a pigment. Melanin. And this melanin is going to give your skin a dark complex. Getting a point. In negroes and blacks, more melanin pigment activity is there. Or no. Tell me, dear. More melanin pigment activity is there. Agreed? So it acts on melanocytes and stimulates synthesis of melanin by melanocytes. Now, I will talk about posterior lobopicetry over here. There are two hormones. One is oxytocin. And another is vasopressin. Oxytocin is there for contraction of a smooth muscle. Having two roles. One is during childbirth, which is known as parturition. It brings about contraction of uterus. Another is milk-releasing hormone. Oxytocin is responsible for two functions. Agreed, everyone? So please understand the difference between milk-synthesizing hormone and milk-releasing hormone. Vasopressin is known as anti-derivative hormone. Neurotic hormone. Let's see. What is diuresis? It is loss of excess water through urine. It is loss of excess water through urine. So that means anti-derivative. What will be the function then? It is against the diuresis. It means it conserves water. Question is there. During winters or after drinking alcohol, frequent urination is there. Because of which hormone? First is growth hormone. Second is follicle-stimulating hormone. Third is ADH. And fourth is none of these. What do you people think? What should be the answer? It is due to ADH. The hormone-involved, I will say, ADH. What happens after drinking or in winters? Secretion of ADH is going to decrease. If it is there, it is, you can say, conserves water. That means less frequent urination will be there. And if it is not there, more and more water will be lost through the body. In that case, what will happen? More urination will be there. So it is there. In absence of ADH or hyposecretion of ADH, a disease is going to be there. That is known as diabetes incipidus. Diabetes incipidus. So one is diabetes mellitus. That is due to insulin. Yes, mesopressin is only known as ADH. No issues in that. It's another name is anti-diabetic hormone that is ADH. Everyone, do you people have any, you can say, doubt in that growth hormone? Hyperssecretion will cause zizentism and hyposecretion will cause dwarfism. The hyposecretion means less secretion, hyposecretion means more secretion that is there. Yes, let's see here. Some more hormones are there. I will let you know. See, one is penial gland. It is going to secrete melatonin. This is a hormone which is going to maintain your circadian rhythm. It is the normal daylight. Just a minute. Just a minute. Let's see. Circadian rhythm is due to melatonin. One thing you people can hear, jet lag. Do you people know what is jet lag? Do you people know what is jet lag? What is jet lag? Am I audible to you? Yes. Yes, when we travel far in that case. So melatonin is responsible for that. Let's see. One thing is there. Circadian rhythm, jet lag is there. Normal diagonal rhythm is maintained by this. Now, one significant thing that you people should remember. It is responsible for fair complex. So can I say MSH and melatonin act again against each other? Can I say that? I will say MSH and melatonin against each other. Can I say that? And when a hormone act against each other, that hormone is known as antagonistic hormone. Yes or no? So are MSH and melatonin are antagonistic hormone? Is it there or not? MSH and melatonin are antagonistic hormones or not? Tell me that. Tell me here. Is it like that? Let's see. Sorry. Yes. Are you saying yes? So any hormone that is acting against each other is known as just give me a minute. My headphone is getting down. Am I audible now? I have changed the headphone. That is why I am asking. Am I audible to you people? Yes. Let's see. Melatonin is there. Now thyroid is there. No issues. Thyroid is going to secrete a hormone known as thyroxine or this is only T4. T3 is also there. Another hormone that is secreted by thyroid is, by thyroid itself is calcitonin. Is calcitonin. By parathyroid gland, one hormone is secreted known as PTH or para-thermon. Pancreas is going to secrete. It is having a group of cells that is known as islets of Langerhans. This is going to have principally two types of cell. One is alpha cell. One is beta cell. Principally I am saying otherwise four types of cells are there. One hormone is glucagon. Another is insulin. Insulin is secreted by beta cells. Yes or no? Everyone? Glucagon will increase the blood glucose level. It will decrease the blood glucose level. Agreed everyone? Yes. Aditya is saying yes. Have you any doubt? The hormone that is going to increase the blood glucose level will be known as hyperglycemic hormone. Hyperglycemic hormone and here the hormone which is going to secrete, you can say that is going to decrease the blood glucose level is going to known as hypoglycemic hormone. Everyone? Do you people have any doubt in this? Do you people have any doubt in this? No. Yes. Let's see. One is adrenal gland. Adrenal gland. I am writing over here. Adrenal gland is going to have two parts. The outer part is known as C over U. First the inner part and then the outer part. The inner part is going to be known as adrenal medulla. And the outer part will be known as adrenal cortex. Agreed? Adrenal cortex. Adrenal cortex is going to secrete three kind of hormones. One is Mineralo-Corticoids. Everyone? One is Glucocorticoids. Another is sex corticoids. Adrenal medulla is going to secrete two hormones that is known as Adrenaline and Noradrenaline. That is known as Adrenaline and Noradrenaline. Adrenaline and Noradrenaline is also used for the same hormone. Glycemic. Glucose. Hypoglycemic. Hypo means less. Glycemic. In blood glucose you can say. Amic word is used for blood. Glyce for glucose and hyper for more. Hyper for less. Glyce for glucose. Amic word is there for blood. So high blood glucose is hyper glycemic condition. Low blood glucose is known as hypoglycemic condition. You know the chief mineralocorticoid in your body is Aldoestero. And the chief glucose corticoid in your body is cortisol. It is a sex corticoid. It is frozen and protesteroid only. See over here. Now we will talk about gonads. Omery is going to secrete estrogen, progesterone. One hormone is relaxing. What happens during childbirth? It dilates birth canal. Testis is there. Testosterone is the chief hormone that is going to be secreted. And you know what is the group? Testis belong to a group of hormone known as endrogens. Endrogens is the group of hormone. And testosterone is the individual hormone. Yes or no? Everyone? Do you people have any doubt in that? Agree? Everyone? Everyone. Do you people agree with this? Say yes or no please. Yes. After this you people should go and read your book very nicely. Okay. In that much time what we can discuss and what are important that we have done already. Okay. You read your, you can say textbook and ask me doubts. From you can say whatever section you want to ask. Okay. You people can send your doubts in between the class also means every Sunday class is there. So you can send the doubts. I will solve. Tell me. I'll just don't do. Yes. A great question. See over here. I have told you people that kidney partner. That kidney partner. Let's see. Just give me a minute. Here is it. Here is it. Let's see. Let's see. This is your distal convoluted. Let's see. From here only the testosterone will work. Will take out Na plus and with that water will also come. Means it helps in retention of Na plus inside blood. It helps in retention of Na plus inside blood. It is absorbing Na plus from you. You can say the thing that is going to be there and which will form the urine. Yes or no. From distal convoluted to fuel. It will reabsorb Na plus. Yes or no. Tell me here. I'll read out. Is it clear now? Aditya? Yes. So if you have asked me a question. I'm going to tell you something more. Let's see. The testosterone is there. What it will do? It will increase Na plus. So in blood along with Na plus water will also come. So blood pressure will increase. And it leads to decrease K plus in blood. Because secretion of K plus is there. It will secrete K plus outside. Yes or no? So if somebody have hypersecretion of aldosterone. What do you think? What will happen? What do you think? What will happen? Tell me here. In that case in the low potassium. Low potassium. Yes. Potassium level will decrease in blood because it is removing it from the blood. Agreed? Everyone. If you people have any doubt in this segment. You can ask. You people can take two minutes for that. You people can take two minutes. You can rethink once. Read your. You can say textbook very nicely. Questions are going to be there from that book only. And apart from that, you can see my notes also. That is going to help you people. Now one is nervous system. One is next was nervous control and coordination. So I will talk about nervous system. I will talk about human nervous system. Do you know what is there? Human nervous system is divided into two parts. One is one is central nervous system, which is CNS. Another is peripheral nervous system, which is PNS. Agreed? Actually, what happens? The basic idea is this is your brain. This is your spinal cord. This is brain. This is a spinal cord. And this is organ. Getting a point from CNS. Some nerves will originate. That would connect a spinal cord to organ or brain from the organ. Yes or no? That is so, see over here. Brain and just give me a minute. Let's see over here. Here, here, brain is there. And the spinal cord is there. Two things are there. The nerve originating from the brain that is known as cranial nerves. What is there? Peripheral nervous system consists of 12 pairs of cranial nerves. And 31 pairs of spinal nerves. You people can see the nerve originating directly from the brain is the, that can also supply the organ. And a nerve that is coming from the spinal cord that is also going to supply the organ. So nerve originating from brain is known as cranial nerves. And the nerve originating from the spinal cord is known as spinal nerves. Everyone, do you people agree now? Peripheral nervous system is divided into two divisions. Peripheral nervous system is divided into two divisions. One is somatic nervous system. Another is autonomic nervous system. Tell me, what is somatic nervous system? Do you know? You people have two types of muscles also. One is voluntary muscle and one is involuntary muscle. Somatic nervous system is going to supply escalated muscle. Means, this is under control of your will, of your will. And here autonomic nervous system, it supply the visceral organ. Do you people know what is visceral organs? Like your heart is beating. Can you control that as per your will? If you want to stop, can you stop your heart? No, that is autonomic. Okay, your GIT is working, gastrointestinal tract is working. What do you think? Is that under your control? No, everything of that kind will fall under autonomic nervous system. Do you know? Now, autonomic nervous system is there. Autonomic nervous system is there. It is having two divisions. One is somatic sympathetic nervous system and one is parasympathetic nervous system. Do you know what is sympathetic nervous system? It is going to work in emergency. When your body is faking, you can say facing some kind of emergency. And it is going to be there under normal condition. It is going to be there in the normal condition. Agreed, everyone? Now, what kind of emergency? Imagine a condition. A naja naja is there behind you. Do people know what is naja naja? What is naja naja? Tell me. What is naja naja? That is cobra. Okay, that is cobra. Snake is there. If that snake is behind you, what all things will happen to you? That will fall under sympathetic nervous system. Let's see. When a snake is behind you, what will happen with heart rate? Or some fearful? Yes. Increased heart rate. What will happen to respiratory rate? What will happen to respiratory rate? Yes, Raghav is saying that it will increase. Yes, you are right, Raghav. What is respiratory rate? Try to understand. When a naja naja is behind you, will you people think that I am going to eat something, then after that I will run? I told if some no. Surely you are not going to do that. Or you are thinking I will have Maggie after that? No, immediate action. I will not eat. Exxon of GIT, gastrointestinal tract, will decrease all the time. Will decrease all the time. Okay, what all exxons are there? Please tell me here. What all exxons are there? Please tell me here. C over here. What all is going to happen? Please C over here. Yes, decrease means secretion of saliva. What do you think? Should it increase or decrease? Secretion of gastric glands. Should it increase or decrease? Paristalsis. Should it increase or decrease? Everything should decrease. So if they will ask, you can think the situation and you can answer. Okay, now, blood supply to skeletal muscle. What do people think? What should happen? Blood supply to skeletal muscle. It should increase. Yes. Blood supply to skeletal muscle should increase. Blood supply to brain. And all the opposite exon will take place in simple parasympathetic nervous system. All the opposite exon will take place in parasympathetic nervous system. Yes or no? Heart rate. Decrease. Respiratory rate. Decrease. Exxon of GIT will increase. Now, we'll talk about we'll talk about neurons. Rather, we'll talk about nervous tissue. We'll talk about nervous. Do you people know what is the origin of nervous tissue? There are two kinds of cells that are there. One is neuron. Another is neuroglial cells. One is neuron. Another is neuroglial cells. Yes or no? Neuron is actually it can detect, can conduct, transmit the impulses. Another is neuroglial cells. Another is neuroglial cells. They are supporting in exon. Supporting cells. Agreed? A straight way I will talk about neuron. A straight way I will talk about neuron. Let's see. Let's see what is there in the neuron. Everyone. Nervous tissue. Neuron. How many parts are there in the neuron? How many parts are there in the neuron? See, many kind of supports are there. I will say. Let's see. If you have asked, I'm going to explain it to you. Aditya is saying what kind of support is needed. Let's see. Neuroglial cells is there. It is of many types. Astrocytes. Oligodendrocytes. So on. See, like oligodendrocytes is going to form myelin in central nervous system. Swan cell is going to form. Myelin seed in peripheral nervous system. Microglial cells are there, no? They come from blood. They are phagocytic cells. That means that it is not going to let anything to infect. It will not let anything to infect the brain. Any bacteria or something. Yes or no? Done? Aditya? Got it? Yes. Neurons are having three parts. Chiefly. Three parts chiefly. And they are dendrite, cell body, and exome. What are dendrites? Dendrites are going to carry information towards the cell body. What is the main site of processing the information? And what exomes will do? Exomes will conduct impulse away from the cell body. Do you people agree with me? Do you people agree with me? Tell me. Tell me, dear. Any doubt on this? Yes. Now, you can see in exome, do you know? This black one is swan cell. This is swan cell. And around the swan cell, it is wrapped by myelin seat. It is wrapped by myelin seat. Yes or no? It is wrapped by myelin seat. Everyone? Yes. See, at places myelin seat is absent. That is known as node of Ranveer. Getting my point. It is absent. It will come over here. This is known as exome terminal. Exome terminal. And that is going to end in a swollen end. That is known as synaptic knob. That is known as synaptic knob. It contains synaptic vesicle. In which neurotransmitters are there? Yes or no? In which neurotransmitters are there? You can ask me, sir, what is the role of neurotransmitters? Later on, I am going to discuss with you people. Synapse. At that place, I will let you know the function of neurotransmitters. Everyone. Do you people agree? Now. I will be talking about types of neurons. Types of neurons. Yes or no? Tell me. Types of neurons. On the basis of direction of conduction. There are two types of. There are two types of neurons that are there. One is known as afferent fiber. And one is known as efferent fiber. One is known as afferent fiber. One is known as efferent fiber. Agreed? Afferent. It is carrying impulse towards central nervous system. Means from the organ. It is taking the impulse towards brain or spinal cord. It is also known as sensory fibers. Efferent means it is going to come. Or it is going to take impulse away from CNS to the muscle. This is known as motor fibers also. Do you people agree? Do you people agree? Afferent and efferent fiber. Any doubt in that? Is it clear? Tell me dear. Everyone. I think you people should reply. Okay. All of you are sitting in the class. So please interact. See over here. Now. One is fiber. One is single neuron. On that basis nerve is of three types. One is sensory. One is motor and motor. And one is mixed. Sensory is there. One fiber now. Which is having only afferent fibers in one direction. Wrapped into a seat. Mixed nerve having fibers which is conducting in both the direction. Sensory as well as motor. And motor nerve only have. Fiber that is supplying. From CNS to the organ. Yes or no everyone. Everyone tell me dear. On the basis of presence or absence of myelin seat. On the basis of presence or absence of myelin seat. One is myelinated neurons. Another is on myelinated or non myelinated neurons. One is myelinated neurons. One is non myelinated or unmalinated neurons. See over here. Myelinated neurons are there in which Swan Cells secret. Myelin seat around the exon and non. Myelinated is there. Swan cells do not secrete myelin. It's around exon Swan cells are present in both the cases. Swan cells are present in both the cases. wherever my linseed is there at that place exon appears white is exon appears white is yes or no tell me dear wherever my linseed is there at that place exon is white is yes or no you got tired are you people tired now okay let's see my linseed is there which is around the exon so on cells are present in both the cases and wherever my linseed is there it appears white is now do you people know about grey matter and white matter see this is cerebral cortex of your brain see how cells are arranged like this now in the outer area cell bodies are concentrated so that is made up of grey matter why grey matter and why white matter because exons are there in the inner area and wherever my linseed exons are there what will be the colour wherever my linseed exons are there yes so white is the outer part of brain is known as you can say made up of grey matter and inner part is no made up of white matter do you people agree with this agreed just a minute yes everyone are this saying something and you repeat nothing is there in the outer part cell body is there and in the inner part exon is there so cell body is going to make things grey and wherever exon is there what kind of matter will be there tell me wherever exon will be there which is my linseed what is the colour white with my linseed so you see inner part having exon with my linseed so colour of inner part will be white and you can say outer part will be grey so can I say in the brain the outer part is made up of the outer part is made up of grey matter and the inner part is made up of white matter can I say that tell me dear can I say that and opposite it is true for spinal cord the spinal cord having inner part made up of grey matter and outer part made up of white matter you people can think upon this for a minute be very sure about this be very sure about this yes got it now have you people read you can say have you people read about this formula resistance is equal to rho l upon a do you people know about this formula these formulas yes the thing is there the neuron is going to follow the same rate of conduction between faster in shorter and thicker neuron in thicker neuron resistance will be less so more SPD conduction will be there and in the shorter neuron also understood do you people agree with this point of mind everyone yes clear let's see on the basis of cell processes it is unipolar one cell body is there and one exon is there that's all bipolar this one one dendrite one cell body and one exon multipolar that I am made over here this is many dendrite and one exon and one is pseudo unipolar it comes like this as one divided into two it looks like it is unipolar but actually it is bipolar so this is there agreed it is there in the retina of eye it is there in the cerebral cortex it is there in the dorsal root of spinal cord later on we will see that unipolar it is there in the non vertebrate invertebrates and non coordinates actually agreed everyone any doubt in this yes let's see we'll talk about nerve conduction we'll talk about nerve conduction we'll talk about nerve conduction let's see what do you people know about the nerve conduction can you suggest me something see this is the diagram of exon actually what is conduction meaning of conduction everyone what is the meaning of conduction how impulse travel along exon how impulse travel along exon electric signal jump downwards the zone jumping from one note to another it will become solitary conduction here it will become solitary conduction yes or no solitary conduction yes or no later on we will see I am going to talk about nerve conduction over here I am going to talk about nerve nerve conduction over here let's see I want to make few points over here that is logical from the evolution point of view where the cell originated where the cell originated in which part is it in the water or in on land wherever it is in water Raghav is saying water Raghav which kind of water is it ocean or fresh water bodies like river and all is it ocean or not Raghav salt water Aditya saying salt water so from that point of time only our cells are adapted that outside it as you have told salt water what is there in the salt water NSEL is there no yes so from that point of time only our cells are adapted like outside the cell all of us in a plus concentration is on the higher side in a plus concentration is on the higher side yes or no everyone yes same is there in our exon also you see outside in a plus concentration is 141 milli equivalent per liter K plus concentration is more 4 milli equivalent per liter even if you do not remember it exactly no issues is issue is there agreed no issue is there everyone inside in a plus concentration is 14 milli equivalent per liter and K plus concentration is 139 milli equivalent per liter any doubt any doubt here clear what I want to make you can say the point I want to make over here the point is outside in a plus is more and not slight difference difference is there rather it is many a times more than the inside around 10 times more yes or no and the inside K plus is more everyone yes only Raghav is saying yes anybody else having doubt I told Hariharan is also saying yes I told outside in a plus concentration is more and inside K plus concentration is more yes or no everyone rest can answer also others should also try dear have you any doubt in this have you any doubt in this tell me yes let's see over here now in the membrane I have different types of channel and pumps what is the difference between channel and pump what is a channel and pump see channel is because you people know that your cell membrane is like this same is the case with exolema also it is like this now a protein should cross the cell membrane like this every agreed everyone agreed everyone this protein is going to form channel channel is there channel allows movement according to concentration gradient means higher concentration to lower concentration like this is voltage gated in a plus channel whenever it will open and a plus will move from outside to inside cannot move from inside to outside because if you are moving anything against the concentration gradient what you will require you will require ATP yes or no and that is the function of a pump yes or no everyone yes Raghava is saying yes let's see so this is voltage gated sodium channel voltage gated potassium channel and sodium potassium pump is there and there are some leaky channel which is always open which is always open agreed you people are clear with this concept now now there is a concept of three salt potency here what is three salt potency here try to understand my point you have to open a gate you have to open a gate you require some minimum force to open that gate yes or no like in your in your house one heavy gate is there gate is very heavy and you have to open that gate if you will try to open that gate with with the help of a finger will you able to do that gate is him no you will increase the force the minimum force at which the minimum force at which you are going to open you you will be able to open that that gate that force will be known as three sold yes or no the minimum force yes or no everyone yes what will happen three sold you people understood if you will apply a force which is lesser than three sold will you be able to open that gate lesser than three sold no and what if you are going to apply a force greater than three sold it will open so I will like to define over here three sold potential is the minimum potential required for conduction of impulse means less than this cannot be conducted so some three sold stimulus or potential cannot be conducted some three sold potential or stimulus cannot be completed you can say cannot be conducted yes or no agreed some three sold less than three sold same thing everyone yes or no tell me dear yes so so what will happen you see when a three sold stimulus arrived yes or no that will lead to opening of voltage gated sodium channel everyone will see you see here the channel is closed channel is closed and here you can see it is open it is open it was like this earlier now it is like this so what will happen if this channel is open sodium will flow in yes or no when a three sold stimulus arrived that leads to inflow of sodium inside the exo plasma yes or no exo plasma is the cytoplasm present in exon isn't it tell me tell me dear yes yes of course now see over here what I am to tell you sodium has flown in flown in that is known as influx of sodium ion arrival of three sold potential opening of sodium potassium channel sodium channel sorry not potassium and that lead to influx of sodium ion yes on everyone everyone three sold stimulus has arrived opened this gate that lead to movement of sodium from outside to inside from higher concentration to lower concentration yes or no everyone yes understood now important thing you see earlier outside was positive inside was negative earlier outside was positive inside was negative here see what is what is the difference that you people can see from here to here lots of sodium ion has you is there that has made things positive over here that has made things positive over here yes or no due to influx of sodium ion what happened over here things becomes positive it became positive yes or no everyone understood or not yes and do you people know that current flows from positive to negative charge do you people know yes do you people know current flow from yes so you see here the conduction has started now it will move it will open sodium channel present ahead and conduction will take place in this way only now you try to understand my point so how conduction has started how conduction has started it has started due to influx of what sodium ion everyone it hasn't started yes influx of so now you see the problem is the opening of voltage created sodium channel is short lived short lived no issues here is short lived now you see the channel get got closed the channel got closed here you can see sodium channel is closed now yes or no everyone the sodium channel has opened lots of sodium came in now the channel is closed what do you think change is sodium got trapped inside yes or no sodium got trapped inside yes of course it got trapped inside now it will repel this potassium let's see this is your potassium channel this is your potassium agreed everyone here is the potassium channel try to understand my point what I am to tell you here sodium is repelling the potassium now potassium moved outside yes or no due to opening of potassium channel everywhere yes now you see if you will remove positive charge which were present over here which were present over here positive charge which were present over here now it became negative again agreed now it became negative again everywhere here it is negative you can see here it became negative like what had happened what is there you can say initially so what happened first influx of sodium ion then movement of potassium ion outside that is efflux of potassium ion yes or no can you people see any difference between this condition and this condition difference that is there can you see any difference tell me dear any difference is there yes more sodium inside and more potassium outside and that is not at all that is not at all a normal condition then comes sodium potassium pump into play then comes sodium potassium pump into play what will happen try to understand my point now sodium potassium pump will take 3 n a plus 3 n a plus outside and 2 k plus inside 2 k plus inside to reach the resting state to reach the resting state yes or no tell me dear everyone yes so how conduction has started how conduction has started due to influx of sodium ion then efflux of potassium ion is there and then again sodium potassium pump will come into play to reach the resting state yes or no everyone are you people clear about the definition of 3 salt potential definition of 3 salt potential yes now I am going to tell you people few more definitions see over here inside is negative and outside is positive how can I how can I differentiate or different do you people know about potentiometer and all potentiometer what we do with that we measure the potential difference something like that no yes what have I done I have taken a very very delicate these are there in the labs I have insert electrode over here and electrode over here electrode over here and electrode over here and I have connected it to the potentiometer will I be able to you can say measure the difference in potential between inside and outside can I do that hurryer and is saying yes sir the is it like that if I will insert electrode over here and one on the surface and connect them with potentiometer will I be able to differentiate between you can say or we will be able to find out potential difference between inside and outside of the membrane agreed yes and this time conduction is taking place or not conduction is taking place or not is it taking place no it is not taking place so potential inside minus potential outside at resting a state is known as resting membrane potential yes or no is known as resting membrane potential and it is minus 70 millivolt 2 minus 90 millivolt and when this difference potential inside minus potential outside we will do when conduction is going on when conduction is going on that will be known as x n potential so you people should be clear with the definition of potential definition of potential definition of resting membrane potential and the definition of definition of x n potential that is there yes or no agreed everyone do you people have any doubt in these three points tell me agreed yes we will meet you people in the next class ok good bye