 Hello everyone, am I what able to you? Am I what able to you? Am I what able to you? Tell me dear, say yes or no? Yes. What are we discussing in the previous class? Tell me, what are we discussing in the previous class? Pandicular system. Let's see. I am going to tell you the Pandicular Escalator. I am going to tell you the Pandicular Escalator. Let's see. Pandicular Escalator. Let's see dear. We have a Pandicular Escalator in that it consists of girdles and limbs. It consists of girdles and limbs agreed girdles and limbs girdles is two there one is pectoral girdle and one is pelvic girdle agreed there are two girdles and I have already told you what is the function of girdle it is going to connect limb to the axial escalator it is going to connect to the axial escalator agreed pectoral girdle and pelvic girdle consists of pectoral girdle consists of escapula and clavicle and pelvic girdle consists of coaxial bone consists of coaxial bone agreed agreed pectoral girdle consists of escapula and clavicle and pelvic girdle consists of coaxial bones agreed. Now it shows. Let's see pectoral girdle is two and each consisting of two bones so total number of bones will be four and what about pelvic girdle it consists of two coaxial bones what two coaxial bones getting my point. So there are two pelvic girdle each consisting of one bone hence total number of two. So how many total number of bones are there in the girdle four in the pectoral girdle in total and two in the pelvic girdle in total agreed coaxial bone is formed by fusion of three bones. Elium, ischium and uvis every dear everyone you can write it down the girdle thing after that I will show you the diagrams you people are not speaking we just speak up just a second. Yes, then everyone let's see let's see in limbs upper limb having 30 bone and lower limb also having 30 upper limb having 30 bones and that are humorous radius. Yes, alum, humorous radius alum getting my point they are one carpals are one are eight Metacarpals are five and phalanges are 14 how many total number of bones are there in this upper limb it is 30 and how many bones are there in the lower limb it's femur, it's stevia, it's fibula, it's patella. Each are there in one in one in number Tarsals seven Metatarsals five and phalanges 14 so that is also 30 bones only defense here carpals are eight and Tarsals are seven in number we dear everyone can write it down then everyone. Just a second. Then, now the pectoral garden, let's see dear, we'll talk about pectoral garden, you can see over here. This is the, this is the escapula bone, this one, you can see clearly, and this is the clavicle bone agreed. Can you see both of them. Can you see both of them. See, see this is a scapula. This triangular flat bone is a scapula. This one that you can see over here. This is a scapula, and this asset bone is clavicle asset bone is clavicle agreed. So, let's see over here, if you will see from the dorsal side, this structure is known as a spine of a scapula. A spine of a scapula and it proceeds towards this side as a chromium process process agreed a chromium process. Then, chromium process, you can see the clavicle is going to join the chromium process only in this diagram. Can you observe, can you observe dear. Now, clavicle is going to going to join the chromium process only to form a chromium clavicular joint chromium clavicular joint agreed everyone a chromium clavicular joint. Can you see this and clavicle on the medial side joined to sternum to form a sternum clavicular joint agreed. You people have understood a spine of a scapula and a chromium process. Yes, sir. On the front side, you can see or a quiet process, but or a quiet process. Read process. No, this was in the from the anterior side, you can see it do not articulate any of the bone, rather, it gives attachment to many muscles. Just below the chromium process, you people can observe this thing, the glenoid cavity what which cavity glenoid glenoid cavity glenoid cavity to which head of humorous is going to join. Now, can I say in a scapula, you people need to remember three things. One is the spine of a scapula. The extension is a chromium process only. Is it extension or not? Is it extension or not? Tell me, dear. Yes, and then then the glenoid cavity to which head of humorous joints agreed. Let's see. Then. Yes. And now you can see pectoral girdle consists of a triangular bone scapula and a accept the bone known as clinical. The location is dorsal part of Forex, situated between second and seventh. Getting my point, it is a flat bone triangular bone. It is a chromium process, a spine of a scapula extends that chromium process. Chromium process attaches to clinical and coracoid process situated in the anterior in the scapula and glenoid cavity is present below a chromium process. Getting my point to which head of humorous fits. Done. None of you please write it down. Done. Let's see. We are done with a scapula, especially its extension and in which reason it is situated. Agreed? Done. Now. Another is clavicle. Clavicle is. Clavicle is a bone which is accept also known as collar bone. It joins medially to external to sternum to form a sternoclavicular joint and literally to the chromium process to form a chromium clavicular joint. It is convex in front. You can say when it is close to a sternum and it is kept. When it is away from sternum. Agreed. Medially joins to sternum. It is a accept bone. Literally articulates with a chromium process of scapula. Done. Please write it down. Done. Everyone. This is your clavicle. So. A total cord is done. There are two bones. Noisos. Now we will talk about pelvic girdle. What? Pelvic girdle. Pelvic girdle. You can see there are three bones. Which fused to form the cobser bone. It was. Elium. It was fused. You can see. Elium I am made with orange color. Getting my point. Fuse I am made with red color. And this team I am made with white color. There is a forum inside this team. That is known as observator forum. That is known as observator forum. Getting my point. So cobser bone is formed by fusion of elium. Ismium and fused. Agreed here. And you can see there is a. Blue color cartilage present between the pubis. To form you with symbiosis. To form what? You with symbiosis. Every year everyone. Which is made up of white fibrous cartilage. Which is made up of. White fibrous cartilage. Symbiosis. What is written. That means white fibrous cartilage is present. Over there. On this. A hormone name is relaxing. Hormone. The name. The name of the hormone is relaxing. Getting my point. That hormone is going to work on pubic symbiosis. And dilate it. During the child. Relax it. During the child. Due to which. The birth canal. Dilates. Done here. Agreed. No issues. We're writing for just a second. Okay. Please write. Write it down. I'm going back in a minute. Done everyone. Done. Everyone. Yes. So. Please do it. The concept of relaxing. We are going to study into it. Please. See this team over here. Just a minute. I think my screen sharing. Screen measuring has a stop. Just a minute here. Done. Are we done with the. Just a minute. Just a minute. Done. Done. Done. Done. Done. Done. Done. Done. Done. Done. Done. Done. Done. Done to me. Yes. Let's see now. raft. Have. Humorous Among. You guys humorous. And radius. And radius. Getting the point. Voice moves. Then. These are some data for. Much. Let me explain into view in a another diagram. Let's see. Over here, the humerus, the radius, the ulna, the carpals. These are the carpals. Charity number. Then metacarpals. Metacarpals. Getting my point. And phylenges. Phylenges. So this is there. This is the elbow joint. This is the elbow joint that you can observe. This is the wrist joint that you can see. Later on we will discuss about this under the section joint. You all can write it. Would you like to draw it? Yes, sir. Please draw. Please inform me once you are done. Here is a muscle. Here is a muscle in your shoulders. In this area, you all can observe a prominent muscle that is attached to the deltoid ridge. So if somebody will ask you, deltoid ridge is present in which bone? What will you say? Humerus. It is humerus. Okay, you people draw. I'm just coming from the back. Yes, dear. I'm there. Understood this thing? Let's see. Sir, just a second. We are labelling the wrapping. Okay, please draw. Done, sir. Done. Yes. Can you people observe? Similarly, the lower limb. Can you people observe? Yes, sir. Can you observe? Similarly, here is the femur. Here is the tibia. Then fibula. Okay. Here is a bone over here. Can you see? This is the kneecap or patella. Yes, sir. Patella. Done. Fibula. Tarsals. Metatarsals and phalanges. Done. Done. Now you can observe one thing. In the elbow joint, both the, you can say both the two bones are there. Radius as well as alum. But in the knee joint, it is not like so. Only two bones are there. Your fibula and your femur. Getting my point? Tibia and femur. Fibula is going to join to tibia only. It is not joining to femur. Yes or no? It is joining the tibia only. It is not joining the femur. Do you agree, dear? Everyone? The femur, the tibia, the fibula. Okay. And the patella. Okay. Femur, tibia and fibula. Then tarsals you can see. Metatarsals you can see. Phalanges. There is a change in number of tarsals. Carpals are eight. Tarsals are only seven. Because patella is also known as kneecap. Another thing, patella is a sasmoid bone. Which bone? Sasmoid bone. That means it is derived from or formed by ossification of tendons. Agree, dear? Please sit down. Tibia, fibula. Knee joint, you people have to remember carefully because only two bones are there. Patella is present on the anterior side of it. Not the part of joint. Just a minute. Yes, you all can draw. Femur, tibia, fibula. Tarsals, metatarsals, phalanges. Are you done with this? Sasmoid bone people have a question. What is tendon? Tendon is going to connect the muscle to the bone. Just a second, sir. No issue. Then everyone, let's see. There are a few more things that is there. Let's see. A few things are there for your differences only. You will go and see some questions and you will not be able to solve for that purpose only. Just a minute. I think internet is slow today. That is why again and again things are stopping. Just a minute here. These days my app is not working at times. Yes. Can you see over here? A few more things are there. Here. I have told you that the deltoid ridge part, deltoid ridge or deltoid tuberosity is present on the humerus. Now you can observe one thing. Two things are there. One is olecranon process. One is coronoid process. First coronoid process and then coronoid process. Can you observe in which bone coronoid process is there and in which bone coronoid process is there? It is present at your elbow joint. It is present at your elbow joint getting my point. If you will view it from the anterior side, you will get to know the coronoid process in which bone it is there. Apart from the other skin also. Answer. Yes, you are not there today in the class. Is it ulna? Yes, it is ulna. And where is coronoid fossa is present? Here it is. Likewise, if you will see posteriorly, olecranon process. Olecranon process is present in ulna and olecranon fossa is present in humerus. Done? Done everyone? No issues? No issues? No. There is a magnified view of the wrist and the hand region. You all can see. You all can see. Now patella was the sesame bone of upper limb. Patella was the sesame bone of lower limb. Lower limb means behind limb. And P.C. form is the sesame bone of upper limb. You all can see. Although here also there are two elevations. Bony regions are present, which is sesame in nature. Which is sesame in nature. So for you people P.C. form is important, nothing else. Done everyone? Names you need not to remember. That much you will not be able to remember. That is not at all required. Okay? That is not at all required. This is the actual diagram that I have made. Okay? I have drawn. This is the digital formula. See digital formula is also known as phalangeal formula. Which formula? Phalangeal formula. Two in the thumb and rest of the fingers it is three. So what is it also called? What? Digital phalangeal. Phalanges are there now. From phalanges it is phalangeal formula. Phalangeal formula. Digit or phalanges. Both are the similar things. So this is specific to human? Yes. It is there in the upper limb as well as lower limb. It is similar. Isn't it? So it is specific to humans, right? Yes. It is for humans. I am talking about human. It may be there in others also. But especially at least in human it is like so. Done everyone? We are done. Let's see. We will discuss types of joint. We will discuss types of joint. Basically on the basis of component and movement that is going to be you can say permitted joints are of three types. One is fibros joint. Another is cartilaginous joint. And one more is synovial joint. Agree, dear? Agree, dear? Fibros joint, cartilaginous joint and synovial joint. Do you people agree? And able to see? Yes, sir. Others are not able to see. Only Sraddha is able to see. So yes, you are there today. You are not speaking at all. Sigour is not saying anything. Chagulam is not saying anything. Poza is not saying anything. Ardith is not saying anything. Not even a single word. Neither asking questions. Yes. Let's see, dear. Fibros joint is of three types. One is sutras. One is syndesmosis. And one is interoscis non-drain. One is sutras. One is syndesmosis. And another is interoscis non-drain. See, dear? Cartilaginous joint is synchondrosis. Synchondrosis and symphiasis. Symphiasis. Agree? We will discuss everything. And synovial joint. Let's see types of joint. First thing. Synchondrosis. What is used when at joint, hyaline cartilage is there? If at joint, hyaline cartilage is there. And symphiasis is there. When at joint, white fibros cartilage is there. Dear? Yes or no? You see? So if symphi, like uvic symphiasis is there. In that case, what is there? White fibros cartilage is there only. Symphiasis means white fibros cartilage. This cartilaginous joint. Agreed? Sorry. Everyone? Agreed? Everyone? Tell me dear. No. Synovial joint. So. Synovial. Yeah. So what's epi and diaphysis? Epi-physis is. Epi-physis is. This is the long one. This is it's terminal end, bulging end. It is epi-physis and diaphysis. In between only, hyaline cartilage is there. This is also known as growth plate. On that growth hormone is going to act. And from here only, the elongation of bone will take place. Done here. Done everyone. Noisce. Done. Now. Synovial. Let's see. Synovial joint is this white color structure is the bone. Bone. And can you see. At its end, a blue color covering is there. This covering, can you people see? Yes, sir. This covering, can you people see? What are they? They are articular cartilages. What? They are articular cartilages. They are. Articular cartilages. Done. Articular cartilages. Everyone? Can you observe? What is the function of articular cartilages? It is going to make movement of joint very smooth. Joint very smooth. If articular cartilage is there, joint is going to move as smoothly. Bone is not going to rub against each other. Done. Done. Yes, sir. Yes. You all can call me. First, draw this. Write it down. Then draw the next diagram. First try. Done, sir. Let's see. Seeing this joint, the bone is there. The articular cartilage is there. Agreed. And you see, the white color capsule is there. Yes or no? White color capsule is there. This is known as articular capsule. You all can see. This is known as, this is the joint capsule. Agreed. And inside the white membrane, there is a red color lining. That is known as synovial membrane. Yes or no? That is known as synovial membrane. Yes or no? Done. Yes. Synovial membrane. And synovial membrane is going to, going to secrete. Synovial fluid. Synovial membrane is going to secrete. Synovial fluid. Agreed. Here. Tell me. Done. We will discuss fluid disease also. In this segment itself. Please see to it. Once you will draw, please let me know. Then, let's see here. This is there. Now you see, if in the joint space, what will happen? Uric acid crystal will deposit. Uric acid crystal will deposit. What will happen in that case? Tell me. The patient is going to develop out. Because those crystal will deposit on the joint surface. And when that person will try to, that person will try to move the joint especially in the morning. A soft pain is going to be there because due to deposition of that crystal joint surface is going to be rubbed against each other. Yes or no? Tell me. Tell me. Yes, sir. Yes. After that. In many cases, articulate cartilage is damaged. In many cases, articulate cartilage is damaged. Getting my point, because of damage to that articulate cartilage, what will happen? There is difficulty in movement of joint. And that is known as osteoarthritis. Osteoarthritis. Getting my point. And then rheumatoid arthritis is work. There is a, you can say it is an autoimmune disease in which one antibody known as a pneumatic factor is formed. And that is going to cause fast proliferation of the synovial membrane. More and more synovial fluid will be formed. It is proliferative synovitis. Synovitis means inflammation. If inflammation will be there, permeability of blood vessel will increase and more fluid will be formed because of that extra fluid pressure. You will not be able to move the joint. Yes or no? Passant will not be able to, will not be able to move the joint. And in that case, what will happen? Some crystals are going to deposit. That is granules are going to deposit. That is known as PANAS. PANAS, P-A-N-U-S. So these three disease are there that I have finished over here only. If you are there, that will be discussed. And really here, you people are done with this, understood these three disease. Almost just a minute. Okay. Answer. Everyone done here now. Let's see. Let's see. We have all the types of joint. Sorry. It is given one note only, not in the note. Types of joint that we have described. In that only these joints are there. Please read out fibro joint. First you write down, then I will explain it to you people. Because in that case, you will have fair, fair bit of idea for discussion. Then here. Just a second. Let's see what you can see in this. What you can see in this fibro joint. One bone is there and another bone is there. That is joined by dense irregular. Connective tissue. Dense irregular. Connective tissue. Yes, or no. What have you observed that this you can say. The difference between sutures, synthesis and interosseous memory. This is the diagram of interosseous memory. Okay. What have you different? You can say. Observe. Please let me know in sutures. Bones are very close. It is there in the cranial bones. In sutures. Bones are there in bones are very close. Agreed. No issues. So very little amount of. Very little amount of what? Very little amount of what? Dense irregular connective tissue is present. And it do not provide any kind of movement. You have to go by this only, which is written in NCRT. There is no movement that is there. You will see in the synthesis. This is the diagram of synthesis. Little bit more space is there and you can see some of the amount of. Dense irregular connective tissue and interosseous memory. It is still further more space and more. Dense irregular connective tissue is there. Yes or no. Tell me dear. So very little space. And very little connective tissue is there in the sutures. Slightly more in synthesis. And slightly more and still more in interosseous memory. You people can observe. The distal tubular joint. The distal tubular joint. Very little point. Distal tubular joint. And here is the interosseous memory. Good. Tell me and one a special type of one a special type of you can say one a special type of you can say joint is there in the between the two socket and the tooth. which is joined in to socket with the help of where you don't tell the government that is also a syndesmosis which is known as gomphosis, a special name is given nothing else. Read here, you all can see if you want to draw the diagram you can draw. Getting my point, so three kind of fibrous joint is possible. Dandere. Cancer. Let's see. So you people have understood the fibrous joint sutures, syndesmosis and interosseous membrane. Clearly now cartilaginous joint. It is also going to lack synovial cavity. It also allow a little or no movement. Getting my point, here articulating bones are tightly connected by either hyaline cartilage and fibrocartilage. If it is hyaline cartilage and synconrosis, if it is fibrous cartilage then it is synovial joint. I have told you both examples you people can write it down. Done everyone? Then we'll talk about types of synovial joint. How many types of synovial joints are there that we need to see. Actually you will see now it is based on basically the basic thing is it is based on types of you can say or shape of the articulating surfaces. And articulating surfaces are those part of the bone which is taking part in the joint formation. Can you observe in ball and socket type joint? One articulating surface is like a ball and another is like a socket. Can you people observe? Yes sir. Your shoulder joint and hip joint. Please write it down. It is triaxial joint. It can move in all of them. In hinge joint you all can see in the door of your house, door is connected to the wall with the help of a hinge. If you will observe it is something like that only. Okay. One bone have been deep concave articulating surface and one is having the convex articulating surface and they are going to on the articulating surface. It is going to move only in one direction or one axis actually. No direction. It is the elbow joint, the knee joint and inter phalangeal joint. Yes or no? Let's write down. Yes sir. Done. Pivot joint. We have already discussed. Pivot means a support. Pivot means a support. Pivot means a support. You can see this is acting like a pivot. Okay. I have shown you people in the atlas and axis. We have discussed vertical column atlas and axis and here it is between radius and Allah. You can write that. Done. Gliding joint. What is the meaning of term gliding? What is the meaning of glide? It is the simplest sign of the joint because for gliding the surface should be flatter or flat. Okay. So you can write it down. Gliding joint. Here two articulate surfaces are flat and they can slip over each other a bit. Saddle you people know. Saddle. It is kept in the back of horse. That is known as saddle. Just imagine the shape and compare that shape over here. It is something like that only. It is saddle. Okay. Example you need to remember. Sir could you scroll down? Yes. Down. This one gliding. It is not gliding joint you are asking for. Sir saddle Done. Angular or contoured joint. You see our ellipsoid joint. Again the shape is like ellipse. You can see. It is like ellipse. Okay. You can write this down also. Done here. Done everyone. Now few more disease that is left. Most of them we have discussed. One or two we can see. Just see dear. My senior premise I have told you people you have understood the neuro muscular junction. I have discussed with you people neuro muscular junction. If you can say receptor of a style Colleen receptor of a style Colleen will be damaged. In that case what will happen? Recital Colleen will not be able to join the or will not be able to generate the exon potential in the muscle fiber. In that case what will happen? Hatir will be there. Weakness will be there. Paralysis will be there. Muscular dystrophy I have discussed with you people in detail. That muscle dystrophy muscle protein dystrophy I have told you in that diagram which is connecting the myofibrils to the sarcolema. So if protein dystrophy will be destroyed in that case muscular dystrophy is going to be there. You all know calcium is not required only for muscle contraction but it is also required for membrane stability. See we are going to discuss nerve conduction from sometime now getting my point. I will let you know that from both the sides of the membrane the electrolytes or the charge should be in a proportionate manner. Otherwise the membrane is going to lose its property. If calcium will decrease too much membrane will become unstable and with simple estimation it will start contracting rapidly or wildly. So tetanus is going to be there. If low blood calcium will be there. Which hormone do you think can cause tetanus? It can be caused by parathyroid hormone in case of its hyposecretia because in your blood the level of calcium is maintained by parathyroid hormone. We are going to read that in the chemical control and coordination chapter. Yes dear. Everyone, any doubt in this? Yes. Please sit down. We will discuss nerve conduction after the break. We will be meeting at 6.50. Are you people back? Let's sit here. Nervous tissue. We have to discuss nervous system. We need to know the nervous tissue first. We need to know the nervous tissue first. What is nervous tissue? Tell me. Actually your nervous tissue is first thing that you need to know is ectodermal erosion. Is it ectodermal erosion? Yes or no? Say yes or no? It consists of neurons. It consists of neurons and neuroglial cells. Neurons can detect, can conduct and transmit the impulse. Neurons can detect, can conduct and can transmit the impulse. Everyone? No issues? And another is neuroglial cells. That is supporting cells. One is neuroglial cells. Done yet? Say yes or no? Are you people there? Yes. Neurons. One thing is glial cells constitute more than 50% of the nervous tissue. It constitutes more than 50% of the nervous tissue. Okay. And if you will talk about parts of neurons, it is dendrites, the cell bodies and the exome. Dendrite, the cell body and the exome. Yes or no? Tell me. Let's see. Neuroglial cells are two types. One is macroglial cells and one is microglial cells. Macroglial cells constitute astrocytes, the oligodendrocytes and the so on cells. Astrocyte forms blood brain barrier. See your nervous tissue is very sensitive to your body. Nervous tissue is very sensitive to your body. So astrocyte is going to wrap around the blood vessels, wrap around the blood vessels. Actually it is present between the blood vessels and the nervous tissue. Okay. Anything coming to the nervous tissue that will pass through astrocytes. So anything noxious or harmful, we'll first go to which cell we'll first go to which cell? Tell me. Tell me dear. First go to which cell? Neuroglial cell. Yes. And then oligodendrocytes, it forms the myelinsid in CNS, the so on cells, it forms myelinsid in PNS. Agree dear. Astrocytes, oligodendrocytes and so on cells. Astrocyte forms blood brain barrier and because and because astrocyte is always receiving a noxious stimuli. So there is more chances of developing a tumor which is astrocyteoma, the brain tumor I'm talking about. Yes or no dear? The brain tumor I'm talking about. Yes or no? Say yes or no? Yes sir. Yes. And what about microglial cells? It originates from the blood. It originates from the blood. It is pavocytic in exan and it is mesodermal in origin. It originates from the blood. It is pavocytic in exan and it is mesodermal in origin. Yes or no? Tell me dear. Everyone. Everyone. So can you solve this question? Solve it. Can you solve this question? Yes sir. It is microglial cells. The neuron is going to consist of dendrite, cell body and exon. You all can write this thing. Please write it down and then we will move to the next diagram. Done? Are we done? Yes sir. Let's read it here. Now parts of neuron. These are small processes are known as dendrite. Okay. This structure is cell body and this is exon. This is exon. Are we dear? Exon. There are three parts getting a point. You can see there is a nucleus inside the cell body. What is nucleus? The main center of any cell, nerve fiber means a nervous tissue cell. That means our neuron. Getting a point and you can observe here is the exon. The point at which exon is joined to the cell body is known as exon-hylock. Exon-hylock. Getting a point. Exon-hylock. Then you can see over exon. There is a covering known as Mylien seed. And here is the swan cells. Read. Because Mylien seed is wrapped over the swan cell only that is why you can see this elevation. You can see this elevation. Yes or no? Are we dear? Yes sir. Dendrite is there, cell body is there and exon is there. You can see at places, the Mylien seed is absent. That is known as node of reindeer. At places, the Mylien seed is absent. That is known as node of reindeer. Are we dear? It is known as node of reindeer. At this point, lots of channels and pumps are present. At this point, lots of channels and pumps are present. Read everyone. Now you can see one thing. This is exon terminal which is terminating into synaptic node. Synaptic node. It contains synaptic vesicle. But it contains synaptic vesicle. Read. Read everyone. Now you can observe few things inside the cell body. Can you see these small granules? This is known as Nestle's granules. Nestle's granules are rough endoplasmic reticulum. So you can, and at places, it is also written as ribosome. It is rough endoplasmic reticulum. At places, it is written as ribosome. Nestle's granules are present in dendrite and the cell body. Where all? Dendrite and the cell body. Done here? Yes sir. Dendrite and the cell body. Dendrite and the cell body. It is absent in exon. Being rough endoplasmic reticulum, you people can understand what should be its function. It is protein synthesis only. Yes or no? Tell me. Yes or no? Yes sir. Yes. You all can write it. Are we done? Sir, just a minute sir. We are done here. Let's see. Let's see. I have made a magnified view of this one over here. This is synaptic recycle. This is synaptic recycle. You see. Synaptic no, which is going to contain synaptic recycle and inside synaptic recycle what is present? The neurotransmitters. What is present? The neurotransmitters. Neurotransmitters can be excitatory and can be inhibitory. Okay. Excitatory is going to conduct the impulse. Reading my point. Further, inhibitory is going to stop the conduction. See over here. Neurotransmitter. If a stylocholine is a neurotransmitter, that neuron is known as cholinergic fiber. And if you can say a neurotransmitter is a stylocholine that is known as adrenergic fiber. Done here. So cholinergic fiber and adrenergic fiber. You all can see over here. Done. Done everyone? Done everyone? Sir, just a second. Done sir. Done. Now. See, actually, we will talk about types of neurons now. On the basis of direction of conduction, there is afferent fiber and effluent fiber. Yes or no? Afferent fiber is one that carries impulse towards the CNS. Afferent fiber is one that carries impulse towards the CNS. Every deer and efferent fiber is one that carries impulse towards the CNS. Okay? This is afferent fiber. This is efferent fiber. Agreed? Yes. Then, nerve is going to be of three types. Sensory, motor and mixed. Sensory, motor and mixed. Sensory, nerve which is purely sensory, it is having only afferent fiber. The nerve which is purely sensory, it is only having afferent fiber. And the nerve which is purely motor is only having efferent fiber. Because it is taking this thing, this is motor. And in mixed nerve, it is both afferent and efferent fiber. Yes or no? So, neuron is something else. You can say nerve is going to contain lots of neuron. Lots of neuron. Yes or no? Yes sir. See you. Then? Yes sir. Let's see. On the basis of presence or absence of myelinase. Neurons are of two types. One is myelinated, another is non-myelinated. See, what are the differences? Let's observe first. Swan cell secretes myelinase. Swan cells do not secrete myelinase. That means swan cell is present in both the cases. Okay. Getting my point. Wherever myelinase is there, it will look whitest. It will look whitest in appearance. Okay. And wherever, two kind of matter is there in your nervous system. One is white matter, another is gray matter. Wherever myelinase is there, that will be white matter. And wherever myelinase is absent, that will be gray matter. Yes or no? So, you people can observe. This is the brain of yours. Cerebral cortex. In the outer side, what is concentrated? Is it exon or the cell body? Exon or the cell body? On the outer side I'm asking for. What is concentrated on the outer side? Tell me dear. Cell body. Cell body. Is there any myelin present on the cell body? No, it is not present. So, outer side myelin is absent. So, it will look gray. And inside, it is myelinated exon. So, it will look white. So, outer side of cerebral cortex is made up of gray matter. And inner side is made up of white matter. It is opposite in case of spinal cord. Inner side is gray matter. And outer side is white matter. Yes or no? Tell me dear. Yes, sir. Now, what is the neurolemur? This is the exon. This is the exon. And outside exon there is, there are cells. And those cells are known as what? wherever myelin is not there, exon cell itself is going to make a cover. wherever myelin is not there, exon cell itself is going to make a cover. And that cover is known as what? neurolemur. That cover is known as what? neurolemur. Yes, sir. Everyone, now this one. One more thing. Have you seen this formula in physics? R is equals to rho L upon A. Yes, sir. Same is followed by neuron also because neuron also or neuron do have electrical conduction only. Neurons do have electrical conduction only. So, R is equals to, so longer neuron having more resistance and thicker neuron having less resistance. You people can agree with this point of mind. This point people can read first. Then I will give you time to write it down. Yes, sir. You can write it down. Especially the neurolemur, neurolemur thing. Myelinated, non-myelinated. Done dear. Are we done with this? Let's see. On the basis of cell processes, then writes and exons are cell processes. Yes or no? They are unipolar. They are bipolar. They are multipolar and they are pseudo unipolar. You can see over here. Actually what happens? Actually what happens? If you will see, if you will see over here, if you will see over here, cell body is there and only one then right is there. That is unipolar. Only one exon and one cell body. It is there in invertebrates. Bipolar. This is the photoreceptor cells and this is the ganglion cell. In between is the bipolar neuron. In between is the bipolar neuron. Read here. Everyone in between is the bipolar neuron. No issues. It connects. It is there in the retina of eye. It connects photoreceptor cells that is rod and cone cells to the ganglion cells. Multipolar. I am made over here. One exon, many dendrites. Noisos. One exon, many dendrites. And one is pseudo unipolar. See, it is coming like this. Only one cell process is there. Then divide into two. One act like dendrite. Another act like exon. Agreed? Dear? Everyone? So unipolar, bipolar, multipolar and pseudo unipolar neurons are there. It is on the basis of types of cell processes. Agreed? It is there in the dorsal root ganglion of spinal cord. We are going to delete this thing from sometime now. Okay, or in the next class. Then everyone, please write it down. Then everyone, then everyone, everyone unipolar, bipolar, multipolar and pseudo unipolar. Then answer. Now, we will talk about conduction of nerve impulse. Let's see what is the meaning of conduction? How are impulse travel along the along the exon? It is the traveling of neuron impulse on exon of the neuron. Let's see here. This is the plasma membrane of nervous tissue. Nervous cell actually, neurons. That is known as exolema. In the exon part, it is known as exolema. Agreed? And you know that plasma membrane is like this, this hydrophilic cell head, hydrophobic tail, like that element is there. Like that element is there. Say yes or no. Say yes or no. This kind of element is there in plasma membrane. Yes. What is this? This is transmembrane protein which will let things go through this. This is known as channel. Yes or no? This is known as channel. You can observe the exon. See, this is the site of plasma present inside the exon. That is known as exo plasma. And this is the extracellular space. See the concentration. In extracellular space, sodium is there in a concentration, 141 mEq per liter and potassium is 4 mEq per liter. In the exo plasma, sodium is 14 mEq per liter and potassium is 139 mEq per liter. Agreed, dear? Agreed, dear? Tell me. Yes, sir. This one and this one. Now, across the membrane, there are two things. One is pump and one is channel. Pump is going to transport against the concentration gradient. That is meant for active transport. And channel is there for passive transport. It do not require energy. It can be voltage gated channel and it can be leaky channel. In many malls, you go and the gates are there. Once you will go, you will be there, it will open up. And after that, it is going to be closed on itself. Yes or no? On its own? Yes or no? Tell me, dear? So that kind of gate is known as voltage gated. Only it will open when impulse will arrive. There are few leaky channels, always open. Yes or no? They all are transmembrane proteins. Getting my point? So you have voltage gated, sodium channel, voltage gated, potassium channel, sodium, potassium pump. And these are the leaky channels. Agree? Agree everyone? Agree everyone? This one and this one. Can you see? Yes, sir. Let's see. Let's see. Can you correlate sodium Na plus in more amount in extracellular fluid with evolution? Can you correlate this thing? Why sodium is present in more concentration outside the cell? Can you correlate? Done. Let's see, dear. Can you correlate this thing? Yes, sir. See, where evolution has taken place? Where the cell has originated? Can you repeat? I told where the cell has originated first. For the first time. Tell me, dear. Is it there in the ocean? Yes, sir. The first cell that has formed? And what is there in the oceanic water? NaCl. So, same here also. All your cells are adapted like it required more Na plus in the extracellular space and less Na plus in the intracellular space. And more K plus in the intracellular fluid and less K plus in the extracellular fluid. Yes or no? Tell me, dear. Yes, sir. Now, this is nerve conduction. You can see inside of the membrane is negative and outside of membrane is positive. So, yes, you are not speaking anything today. Not even a word. Let's see what I want to tell you all. Here, inside is negative and when this kind of thing is there now on both the sides of a membrane, two different kind of charges are there that is known as polarized membrane. What? Polarized membrane. Every dear that is known as polarized membrane. Every dear inside is when two different positive and negative are poles only. Positive and negative are poles only. You people read about these things, no? Dipole and all. So, if any membrane having two different charges on its two sides, that is known as polarized membrane. Are the nerve fibers are, you can say nerve or exo, lemma is a polarized membrane or not? Is it there? Yes or no? Inside is negative and outside is positive. Can you observe? Outside is positive. Is there any specific reason for this? Is there any specific reason for this? Yes, there are three reasons. One, why it is inside it is negative. First thing is inside the exo plasma negatively charged proteins are present. Negatively charged proteins are there. Getting my point, this is one thing. This is one thing. Next thing is in resting state the membrane is more permeable for K plus and almost impermeable for N plus. Sorry, I think I have dictated it wrongly or in the opposite manner. It is impermeable for N plus and permeable for K plus. So, if it is permeable for K plus K plus is more inside. It will move out. It will move out. You are going to remove a positive charge from inside. What will, what it will become? Negative inside now? Say yes or no. Because N plus cannot move. Because it is impermeable at that time. And third thing, sodium potassium pump is electrogenic. Why it is electrogenic? It throws three N plus outside and takes only two K plus inside. It throws three N plus outside and takes only two K plus inside. Agreed? Dear? Done? Tell me? You all can write it down. You all can write it down. These are the important concept that has to be understood. Done? Everyone? Done? Are we done? And so? Let's see. Now I am going to decide a few things. I am going to put a electrode inside the membrane and one on the surface of the membrane. I am going to see where to connect it to the potentiometer and what is the instrument potentiometer known for to calculate the potential differential. So, potential inside minus potential outside when it is a convention that you are always going to differentiate or measure between inside and outside. Inside will come first. That is the convention that is made. Yes or no? Yes or no? If you are going to do like this, are you going to get potential inside minus potential outside? That is the potential difference between the two sides of the membrane. Yes or no? Potential difference between the two sides of the membrane. Yes or no? Say yes or no? Tell me. Yes sir. Yes. Yes or no? So, let's see. It is at the resting state. What is the meaning of resting state in neurons? When no conduction is taking place. When no conduction is taking place. No conduction is taking place. So, have you understood the definition of resting membrane potential? It is the potential difference between inside of the membrane and outside of the membrane when no conduction is taking place. It is minus 72 minus 90 millivolt. If you are going to subtract positive from negative, it will be always negative. Wait dear. Yes sir. Are you people agree with all these things? Have you written this thing? Have you written all these three points of membrane being negative towards inside? Done everyone? Yes sir. Yes. Now, we are going to study the concept of three-sold potency. You may have observed during the rainy season, some of your doors or doors in your house is going to be jammed. Yes or no? Have you observed that? And it is very difficult to open that door. Have you observed or not? Yes sir. Yes, you have observed. So, tell me dear what had happened? You will require a minimum force. You will require a minimum force so that the gate should be opened. Yes or no? Yes sir. That is known as three-sold. Will the gate open if you will apply a lesser force than that of three-sold force? Will the gate open if you will apply a lesser force than the three-sold force? Will it open? No sir. It will not open. Similar thing is there means some three-sold potential is the minimum potential required for conduction of impulse. Anything which is lesser than three-sold will not be conducted. Anything which is lesser than the three-sold potential will not be conducted. Tell me. Yes sir. Everyone, done everyone? Have you understood concept of resting membrane potential and three-sold potential clearly? Yes sir. Conduction among the nerve fibers follows all or none law. Either the impulse will be conducted or will not be conducted. There is nothing like partial conduction that is there. There is nothing like partial conduction that is there. Yes or no? The partial conduction is a myth that will not happen. Either it will be conducted all along the neuron or it will not be conducted. It will be conducted or it will not be conducted. It follows in nerve as well as muscle. It follows all or none law. Now, I am going to tell you how things are getting conducted. Let's see here. The three-sold potential has arrived. That leads to opening of voltage gated sodium channel. That will lead to opening of voltage gated sodium channel. If you are going to open the sodium channel, in that case, sodium will flow in which direction? Outside to inside or inside to outside? Which direction? If you will open the sodium channel, in that case, sodium will move in which direction? Outside to inside or inside to outside? Please let me know, dear. Tell me. Am I audible to you? Yes, sir. The sodium will come in. That will lead to influx of sodium ion. Influx of sodium ion. See, if sodium ion will come in, it makes the membrane positive inside and it remains negative outside. It makes membrane positive inside and it remains negative outside. This happens only locally. Only where the sodium channel is present. Only where the sodium channel is present. Away from it, it is still negative inside and positive outside. Yes or no? Every dear? From positive to negative, the current is moving. From positive to negative, the current is moving. Is it moving or not? Is it moving or not? And this process is known as depolarization. I have told you it is a polarized membrane. Now it is getting depolarized. Yes or no? Every one. So depolarization is a process that has taken place due to influx of sodium ion. Which phenomena? Is it due to influx of sodium ion? Yes sir. Is it due to influx of sodium ion? If somebody will ask you why depolarization is taking place, what will you answer? Because of influx of sodium ion. Now, the opening of sodium channel is short lived. Okay? It is short lived only. It will be closed soon. It will be closed soon, you see. In that case, what happened? Sodium is trapped inside or not? Sodium is trapped inside or not? Sodium is trapped inside or not? Tell me dear. Because without opening the channel it cannot move. Yes or no? Yes or no? Yes. Now this sodium will repel the K plus present inside and opening of K plus channel will take place. That is known as efflux of K plus ion. K plus is moving out now. K plus is moving out. It will make everywhere negative inside and positive outside. Yes or no? It will make everywhere negative inside and positive outside. Yes or no? Because either sodium is moving in or potassium is moving out. The similar kind of charge movement is there. Yes or no? Sodium is coming and making things positive. Potassium will go out, will make the things negative again. Yes or no? Again the inside negative potential and outside positive potential is restored. Yes or no? That process is known as repolarization. Why this repolarization has taken place? Due to efflux of potassium ion. Yes or no dear? Yes or no? Yes. Yes. Others can also answer. Let's see. So and now what will happen? The charge becomes like the initial thing. Charge becomes like this only. Charge is similar but things are sodium is trapped inside and potassium is trapped outside. In that case sodium potassium pump will act. Sodium potassium pump will act. It will throw 3 Na plus out and it will take 2 K plus in. Agreed? Everyone? Yes or no? Yes sir. Done? And it will return to, it will return to the resting state. Yes or no? You all can note down. Read it nicely from NCRT. Let's see. Write it down nicely. Just a second. Done. So all these things are there. We will be meeting in the next class. We will study further. Bye everyone. Good night. Thank you sir. I am sending you the folder.