Transcript for:
Understanding Cytoskeleton and Cell Structures

that are found within the cells and they have many functions okay so the basic function of uh of cytoskeleton is to maintain this uh the shape of the cell okay as you know cells the uh animal cell yeah animal cell especially they do not have any cell wall okay so so in order to maintain the structure of the the shape again the shape and the structure of the of the animal cell so within the animal cell you have cytoskeleton all right so there are there are three types of cytoskeletons all right the first one is the microtubules for the microtubules it has the thickest okay diameter of the tree uh of the other two cytoskeleton uh and then for the microfilament it is also known as the actin filament it is the thinnest component okay uh so the the most common uh a place where you can find microfilament is in the muscle cell okay so it involves in muscle contraction and then uh that is one one example of micro phenomena and then uh the last one is the intermediate filament so for the intermediate filaments it has a diameter in the middle ridge between the the other two okay and then uh for the intermediate filament it is made up of fibrous proteins okay you have strands of protein protein molecules okay that that that forms the intermediate filaments so so because because intermediate filament is made up of fibrous protein so that's why for for fibrous protein for the intermediate filament it is more stable okay the structure is more stable than the microtubules and microfilaments so um microtubules and the microfilaments they are made up of globular proteins so proteins we can classify proteins uh either as globular proteins or fibrous protein okay so microtubules and microfilament is made up of globular proteins right so as you see from this diagram so this is the structure of globular protein globule okay the the subunit is uh is in the form of globules all right um so so this is for actin filament yes it has the thinness okay thinnest diameter and then for microtubule tickers and intermediate uh intermediate uh diameter so so this one intermediate is made up of fibers okay uh fibrous protein panzer it could be a compared to of microtubules and active filament they are made up of subunits of problem globular proteins so it says here microtubules and microfilaments from uh from globular protein which is which is bit like a subunit can be accepted rapidly assembled and disassembled right in filament as fibrous protein okay so this is the overall uh overview for the function of uh of cytoskeleton one so it gives cell mechanical strength support the cell and maintain the cell shape okay and then so why because uh for animal cell it does not have any uh cell wall okay to maintain the shape of the cell it does not have any uh central vacuole okay uh to to cause the cell to be legit so what to what to uh what structure can can uh can maintain the cell at the cell shape is by having cytoskeleton and then okay so next um uh satisfactory cell structure and activities and carrying many organelles okay so um for example for the intermediate filament the intermediate filament one of the function of the intermediate filament is to anchor the nucleus into the uh cytoplasm so that the nucleus will not free it cannot freely move within the cell caloritech structure um upper orbital structure uh animal cell under a microscope you will observe that that the nucleus is located at the center at the center of the cell so so uh so you have the intermediate filament to anchor the uh nucleus in place okay and then the third one certain cytoskeletal uh microtubules interact with motor proteins to produce motility so motor proteins okay this structure um thing on a d you have okay microtubules okay microtubules can act as a track okay for uh for example vesicle to move along the track uh you have for example transport vesicles that is formed from ravial okay so ravi r produces um protein and then package the protein into transport vesicle this transport vesicle it has to move from rough er to the gorky apparatus so how to move the transport vesicle the transport vesicle will move along there the track okay which is made up of micro tubule and in order to move along the track so the vesicle has to attach to motor protein and the motor protein is attached to the micro tubules so then only the the uh the vesicle can move along the track until it reaches the glob the golgi apparatus okay so that's why the gasoline method involved in in motility per girafften uh organelle within cell okay the the movement of organelles within cells and then uh the next one inside cell vesicles is cytoskeleton also involved in cell division okay so one uh the the micro the microtubule for example and the first one that again the microtubules will form it is the component of centrione okay as you know the function of centriole it is the component of centrosome that involves in cell division the the nuclear division the division of cells and in order for cell to divide you have to separate the chromosome into opposite pose so that the daughter cell can receive the chromosome equally okay so in order to separate the chromosome during cell division it requires the microtubules again to form uh to form the spindle fibers all right right okay so uh it says here molecular motors okay vesicles can be transported along microtubules uh using motor proteins so this is motor protein example of motor protein is dynein and the the movement requires energy from atp okay so this is um this this requires energy from hp so the vesicles are attached to motor protein by connector molecules so this is connected molecule example of connected molecule is the actin then the the actin uh complex okay the and then uh the motor protein the indian moves the connector the connected vesicles along vesicles along the the microtubules okay so microtubules track okay track for example to move vesicle from one region to another region within the fluid of cytoplasm right so this is another diagram any sedan okay so here you have the vesicle and uh the the membrane of the vesicle will have receptor okay the membrane of the vesicle will have receptor so the the function of this receptor protein is to attach to the motor protein okay so the motor protein would then attach to the micro tubules so in order for uh to allow the vesicle to move along the microtubule it requires energy from atp okay so from this uh figure from this diagram as you can see so this is actually a vesicle that moves along microtubules that are observed under a microscope this is observed from axon of a neuron okay axon of a neuron so as you know neuron it contains vesicle that contains neurotransmitter the neurotransmitter allowing head okay um structure structure neuron that is then dendrite of the neuron so at the at this region which is the cell body it contains the organelle for the neuron the nucleus mitochondria so it means that in the in the cell body region is where vesicles containing neurotransmitter will produce okay but all the plastic and neurotransmitter are released in the synaptic cleft here yes synaptic clef uh released from the synaptic terminal over here so how to how to transport the vesicle to this end by having microtubules again microtubules that allows the vesicle to move along them along the long axon of a neuron so they within the cell okay uh next so this is another added information um okay so the rule of cytoskeleton the same the same as i've mentioned uh on the in the previous slide so inside cell the vesicles and other organelles can travel to the destination along monorails again provided by the cyto skeleton track can so the cytoskeleton especially the microtubules will self-abstract for the organelle to move from one region to another region within the cell for example a vesicle containing neurotransmitter molecule migrate to the tip of axon via this mechanism second the vesicle that bites off from the from the er we can travel to the gorky apparatus along a cytoskeleton track and then recent evidence also suggests that cytoskeleton may help regulate biochemical activities okay so it means that reaction within cells also um uh involves okay the cytos uh skeleton to regulate the the the chemical reaction okay so next um uh okay this this is the detailed structure of a micro tubule okay of microtubules so microtubule is basically it is a hollow tube okay they are microtubules are hollow tubes uh and the diameter is about 25 nanometer in diameter and then the wall of the hollow tube is constructed from tubulin get tubulin so uh so they are actually globular proteins okay so each tubulin is a dimer so this is one uh typically okay this is these are tubulin dimers okay stapedium exists in paris okay you have the alpha uh two boolean and also you have uh a beta tubulin so that forms a dimer okay so you you assemble the dimer uh together and forms the structure of microtubules okay so this is the basic uh the the the overall uh function of uh of microtubule which is to maintain the shape of the cell okay and then uh uh it acts as compression resisting uh resisting which is good this and then it involves in some utility motion totally it is the component of the flagella of sperm that allows the sperm to be able to swim in flagella and then it involves in the chromosomal movement in cell division okay it is the component of centrioles okay that that forms the spindle fiber during uh during cell division of mitosis or myosis and then uh it involves in organelle movements okay so um next okay so example uh for for for the first example of microtubules the function of microtubules is that it is the component of centrosome and centrioles okay that function in cell division so in many cells it says here microtubules grow out from from a centrosome near the nucleus grow out near masonia it forms the spindle fiber later okay the centrosome is a microtubule organizing center mtoc so in animal cells the centrosome has a pair of centrioles okay so each uh each with nine triplets of microtubule arranged in in a ring so this arrangement is known as nine times three structure again nine times three structures so uh if you look at this diagram okay so this is the structure of centrosome centrosome is made up of two centrioles again the centrioles are aligned like this 93 90 degrees to each other okay so you have two centrioles that make up a centrosome so this is the image under under electron microscope okay so the each of the centriole is made up of nine okay nine to nine triplets of microtubule arranged in a ring gambani [Music] arranged in triplets a triplets microtubule arranged nine times okay that forms ring uh and then the so that's why the strategy bucket nine times three structures okay so most animals have centrosome the two centrioles are at right angle to each other each is made up of nine sets of three microtubules yes so the centriole replicate before the animal cell divides so before animal cell undergo myosis or mitosis the centriole will divide first okay uh we'll replicate first okay so cells ie cells and animals will not have any centrosome with centriole but they have a well organized microtubules okay so plaster will not have a centrosome taffy the other well-organized microtubules that involve in the cell division okay so this is the structure so make sure you know how to draw the centrioles okay the arrangement of the three uh of the triplet microtubules arranged in a ring line okay they say try again and you you try okay so i said looky second mouse and susket okay can you say and then uh you just attach the last uh microtubule with the with the first one attached can attach something like that so then you you have your microtubules okay so um we said to the roughly again so make sure you you draw the structure correctly so something like that all right so centrioles uh each centriole is composed of nine triplets of microtubules so centrioles are usually not found in a plant cells in animals that have they help to organize microtubules okay [Music] okay so the next example for microtubules um [Music] the next one is uh the the next example for microtubules where can you find microtubules it is the component of celia and also flagella okay so by having uh by by having microtubules acid components for the cilia and plasilla so this allows the cilia and flagella to be able to move okay so microtubule controls the meeting of cilia and flagella which is local water advantages of some cells so celia and flagella differ in their beating patterns they can move back and forth okay so they are dependent on cell then they can move back and forth to move uh for example fluid okay uh fluid outside of themselves and then also flagella yep when you move multi adela um it's like a um swimming motion okay i'm just a wave like motion though all right so um so so the meeting uh of cilia flagella will be different so many unicellular eukaryotes are propelled through water by cilia or flagella so for example sperm cell will have flagella okay so it says here so as you can see from the diagram here you have several uh sperm cell okay and then this boom so we'll have uh one flat flashlight okay so the the the movement of the flash of sperm is wave like moonshape okay undulates right wave like motion so uh proportion of sperm cell is an example of flashlight uh local motion and then for the cilia the motion is back and forth motion okay kind these are examples of where you can find uh cilia all right um cilia and flagella can move over the water of of the tissue example the ciliated lining of cilia sweeps mucus containing trapped debris out of the lungs so the air that you breathe in okay obviously it's not clean it contains contaminant okay so the air will be filtered by your hair in the nostril and also by the uh cilia lining the trachea so cells of the trachea will have cilia okay so the function of the cilia is to trap the debris or the contaminant that you breathe in uh and prevent the contaminant from getting into the lungs okay so uh and also you have to take note the cells of the trachea apart from having cells that have cilia they also have um cells that can produce mucus and this cell is known as goblet cells okay the function of the goblet cells is to produce mucus so it means that uh the contaminant that you breathe in okay um it is uh filtered by the cilia and then the the mucus secreted with trap okay it binds with the contaminant and then you you the the movement of the cilia upward causes the mucus and the contaminant to be swept upward and then it enters into the uh esophagus and and into your stomach to be digested okay so the cilia will sweep the mucus with the contaminant and uh enters into the esophagus to be destroyed in the stomach okay and then another place where you can find the cilia is um the cells that lines the fallopian tube or the oviducts okay what is the benefit of having cilia that lies there of that it is to help okay the the the the egg or the ovum or the secondary oxide to reach to the uterus ovary releases the secondary oxide and sodium so how to help in the movement of the egg by the beating uh the the the motion provided by the cilia so ciliato i can push uh the the secondary oocyte forward until it reaches the uterus okay so that is the function of having celia that lines the oviduct okay helps the movement of cilia of the secondary inside okay so it stays here these are elaborations okay so cilia and flagella share uh a common ultra structure so for each cellular flagella what will they have they have a plasma membrane surrounding the microtubules okay each has a core microtubule shifted or surrounded by plasma membrane so this is this is the microtubules okay and then they are covered okay by plasma membrane why because it is part of a cell okay so obviously cell will have plasma membrane so but the arrangement of the microtubules that form the cilia and flagella is different from the arrangement of microtubules that make the centrioles of centrosome 30th century a central offset of centrosome nine triplets of microtubule range in the ring but this one for cilia the arrangement is nine doublets nine doubles of microtubules arranged in the ring milan so nine doubles okay so nine doubles of microtubules centriole nine triplets of microtubule okay arranged in your ring so for this arrangement okay for the cilia arrangement they will have a pattern a pattern we call it as nine plus two pattern so what does nine plus two pattern means so it means that at the center uh here you have uh two single microtubules okay at the center you have two single microtubules so that's why it is called as nine plus two right but if a nine plus zero pattern you will have no you are you will have no microtubule at the center okay so um another common structure that the civilian flagella shares is that they will have basal body okay so best what is best the body that's a better body that anchors the celium and fly gelum to the cell to the main cell okay so the the basal body structure is similar to a centriole so it means that the basal body will have arrangement nine triplets of microtubule the the arrangement of microtubules for basal body is the same as centriole nine triplets of microtubules okay so in many animals the best body of the fertilizing sperm uh flagellum enters the aches and becomes a centriole okay so okay so questioning our head of the spoon okay so this is the flagellum arrangement of the flagella nine triplets of microtubules arranged in a dream uh in the ring okay or nine times three structure the salah [Music] okay but the arrangement you have you have to somehow attach the the flagella to the head of the sperm cell okay so this attachment is done by the basal body so you have here base the body face the body okay so the basal body is here so and the arrangement of the basal body is the same as the centriole chamomile centriole same as centriole okay so which is the nearest when there nine triplets of microtubule arrange in the rings okay so when the sperm cell fertilizes the eggs you need a secondary oocyte sodium scallions the head which contains the dna the partner grenade and also the basal body okay so and then this is the nucleus of the eggs so the nucleus of the eggs deployed sorry haploid haploid so there are kenzani zygote young uh do an approach zygote okay fertilized eggs by the sperm will become centriole okay so in many animals the basal body of the fertilizing sperm uh become become the centriole okay so the next ultra structure that frazella and cilia shares is that they have uh a moto protein which is called as denim structure here is the moto protein or the daily protein the function of the adenium protein is to attach the doublets the outer doublets together okay is to attach the outer doubles together and it also derives the bending movement of the flagella obviously cilia okay so so that is the three common author structure shares by celia and flagella and then another one i don't like status mania which is uh for cilia and flagella they have this one the blue structure here okay the blue these two blue structure which is radial spoke okay that that that attach the outer doubles with the inner doublet and also uh this blue uh structure here okay which we call it as pro protein cross linking outer tablets okay so that is structured radial spoke and also for protein crosstaking outer doublets okay so these are the uh common structures uh shares by cilia and flagella saturated surrounded by plasma membrane and then the arrangement the other nine doublets care engineering and then upper basal body and also the denim protein again also radius pork like acne so those are the ultra structure of cilia and plasylla so it's lagging somewhere so this is the cross this is again the same picture so the e shows you cross section of microtubules for for flagella or cilia okay so they are they arrange many nine doubles of micro tubules and then love two at the center and then they are surrounded by plasma membrane and also again uh okay so paramecium as you can see on the surface you will have many celia okay so this helps the museum to be able to swim across [Music] reader okay so the next one is for the microfilament so for microfilaments uh so microfilaments that function in cellular motility contains protein myosin and also uh actin okay so the structural role of microfilament is to bear tension resisting pulling forces within cells so the microfilament it is made up of actin subunit okay antenna subunit again it is a type of globular protein so they involve for example in muscle contraction maintain cell shape uh help upper involved in changes in cell shape any changes in cells as a cell shape it forms or it evolves in the formation of pseudopodia for example and then also cell motility again and the same example for amino void movement it helps the amoeba to be able to move across water and then also involve in cell division okay so first example uh of uh microfilament is uh it is the component uh within uh muscle cells that that helps the muscle cell to be able to contract okay it says here in muscle cell thousands of item filaments okay so these are active filament the blue strand sorry the the orange strand here okay arrange parallel to one another so they are arranged parallel to one another so the thicker filament composed of myosin the blue purplish color here is the myosin will uh it will be in between the the actin filament okay so muscle contraction involves the shortening of many muscle cells at the same time the movement of the myosin arm will cause the actin filament to contract okay so they they will meet each other uh at this point so they are kind of in this direction right so the next example is uh that involves the microfilament is the amiibo movement so what is amiibo movement it is localized contraction helped by actin and myosin which helps all which helps or drive the movement of amoeba okay so pseudopodia so this is pseudopodia which is cellular extension extend and contract through the reversible assembly and contraction of actin a subunit into micro filament automatically keyword revisible assembly and contraction of actin unit if you look at this diagram so this is a diagram showing you an abiba okay so inside the amoeba you have two distinct region give one region we call it as the gel or the cortex okay the outer cytoplasm and then you have inside here uh which is the inner cytoplasm which is soul the more fluid uh region here okay the more region here so the the the digital region here is more dense this more dense okay it is more dense why because the the active subunit activities that you need young pieces of globular protein so within the region the actin will assemble together assembled okay to form the actin filament so that's why at this region it is uh much denser compared to the soul region it is more fluid why because the actin subunit will disassemble okay disassembled and assemble disassembled and assembled so so that forms the soul region okay uh soul with actin sub unit so the the assembly and the detachment of the actin subunit causes the formation of the sodopodia so it pushes it pushes the cytoplasm forward it pushes the cytoplasm forward and it forms this autopodia that allows the amine but to be able to move forward okay so that is amivo movement so soul is the much fluid region of the cytoplasm all right it's about the idea acting subunit colloidal actin network okay so next uh is cytoplasmic streaming in plant cell so cytoplasm streaming is a circular flow of cytoplasm within cell okay so um so in order to allow within within cell for example india plant cells that has chloroplasts there are numpad acidia chloroplasts okay a mini project for for you to observe plant and animal cell under microscope okay so one one type of plant plant that you can choose for this experiment is for example elodia why because elodia will have thinner thinner thinner leaf okay that you can observe under the under the microscope so alone yeah uh the leaf is green so obviously it contains chloroplasts so once you observe the leaf of the elonia under the microscope you will observe that the chloroplast will will move in a circular motion chloroplast yeah in a circular motion okay so so that uh the movement of the chloroplast okay uh in a circular motion is also aided by the micro filaments and so the next one is the intermediate filaments so intermediate filament is a bit different from the microfilament and microtubules so it is made up of fibrous protein okay tadi and is made up of globular protein but this one is fibrous protein coiled into cables number coiled into cables so uh so it is made up of keratin proteins so creatine proteins and a protein protein that i found in your skin in your nails in your hair okay so so this structure is much more stable so the function of the uh intermediate filament one of it is maintains the shape some of the angular study but this one it uh it is to uh bear tension okay anchor anchorage of nuclears and other other organelles and then from it involves in uh the formation of nuclear lamina okay hello so this is nucleus for example this is within a cell so nucleus uh in order to maintain the nuclear envelope get the in order to maintain the shape of the nuclear envelope so the the nuclear envelope are supported by nuclear lamina here again nuclear lamina in there in inside of the nucleus instead of the nucleus of the pancreas nucleoplasm can okay so the function of the nuclear lamina is to support the the nuclear envelope okay the shape of the nuclear umbrella uh slide okay so it says here intermediate filament uh yeah some will reach in uh diameter eight to twelve nanometer so uh the diameter is larger than the microfilament but smaller than the microtubule so they help support cell shape and fix organelle in place so for example number one the nucleus sits within cage made of intermediate filament fixed in location by branches of filaments that extend into the cytoplasm so it anchors it anchors the nucleus in place and extends throughout the cytoplasm it anchors organelles also okay so the nuclear lamina are made up of intermediate filaments okay and then the next one the the last one example the long axon of nerve cells are strengthened by intermediate filaments so exon the neurons will have long axon okay so in order to maintain the structure of the lung axon it is strengthened by the presence of intermediate filaments so the next one uh is for extracellular structure so extracellular structure um example you can have uh cell wall ecm and also cell junctions okay so um cell wall are only present implied extracellular matrix is all uh only present in animal cell okay because animal cell will not have any cell wall okay so the after replacing an extracellular matrix masonry extracellular matrix all right only in animal cell and then you have cell junction so suggestion there are four types of which we will look at later later so it says here both cell synthesized and secret materials that are external to the plasma membrane so the synthesis of this component okay uh is within cell but they are excreted out okay to be to be component outside of the cell okay so the first uh extracellular structure here is the sarwar so the cell wall is an extracellular structure that distinguishes plant from animal cell so uh other organism that has someone is uh prokaryotes fungi and also some proteins also have saron so the cell wall protects the plant cell maintains its shape and prevent excessive uptake of water okay within within the bloodstream you will have a central vacuole and the function of central vacuole is up is to store water okay and uh so in order to prevent the cell from bursting okay and prevent the cell from taking uh too much water so that's why uh the cell will need we need to have cell wall okay prevent excessive after water and preventing the cell from from bursts and then blood cells are made of cellulose fibers embedded in other polysaccharides and also proteins so you have to remember the the main component of cellulose is made up of beta glucose okay beta glucose is the sub you need for for cellulose okay so the cell wall is made up of multiple layers so you have the primary cell wall which is the thin which is thin and flexible and then you have the middle lamina uh which is thin uh thin layer rich impacting that glues uh the cells together you need some kind of glue okay to attach the cells together so this is done by the protein and then you have the secondary one uh which is the thicker okay the thicker uh part of the wall and then you have uh the plus model mata channels between adjacent plant cell so this is these are plus modes mata k channels between cells the function of the plus models matter is that it allows a substance to be exchanged between cells okay the cells can transport substance uh from from one cell to another cell through the plasmodesmata okay so the next one uh is the extracellular matrix so it says here animal because they will not have any cell wall so it is supported by having extracellular matrix okay so the component of extracellular metrics are collagen ultra glycan complex and also fibronectin okay so collagen are fibers embedded in of proteoglycan complex so collagen so these are extracellular metrics so it is made up of collagen young the blue uh the published structure here and then they are surrounded by uh proteoglycan the the green structure here and then to attach the collagen to the plasma membrane you have a fibronectin okay fibronectin that attaches the collagen to the integrins what are integrins integrins are proteins that are embedded in their plasma membrane integrins okay so you have fibronectin that is that is function to attach the collagen to the integrins of the plasma in brain okay so uh what about proteoglycans photoglycans uh complexes are made up of hundreds of protroglycan uh molecules okay which is a small core protein with a many carbohydrate chain conveniently attached so proteoglycan is basically made up of protein and also carbohydrates okay um you need that fibronectin attached to integrate the embedded air in the plasma membrane so this is the structure of of uh of a petroglycan molecule okay so it has it is composed of protein and also carbohydrates protein and wonderfully carbohydrate okay so that is portrayed glycan protein and also carbo hydride protein core and also uh carbohydrates okay like glycosamine aminoglycan example of gag is chondroitin sulfate okay uh okay so these are the explanation for the integrand totally intriguing are two subunits of membrane protein they are embedded in the plasma membrane and then they will bind to the ecm on the outside and attach to the microfilament on the inside if you look at this diagram okay the and the entry grains will attach to the extra cellular fluid okay through attachment with the fibronectin and it is also attached to the cytoskeleton which is the microfilament inside the cytoplasm okay so this attachment will maintain or strengthen uh the the plasma membrane it's about plasma membrane that is have one and so to maintain that that structure the structure of the plasma membrane it will attach to the ecm and outside and it attached to the microfilament inside the cell okay um since yeah it is in a position to transmit signal between ecm and uh and the cytoskeleton inside so the the the integrand also function in uh signal trans uh signal transduction process signal translation process yeah signals right so the next one is a cell junction you have four types of cell junction plus modes mata tight junction and gap so these are found in animal cell okay animal cell this is only found in plant cell okay so it says you never bring cells in tissues organs or organ system often adhere in interact and also communicate through direct physical contact number eight islamic acid communicate communicate or interact so communication and interaction between cells can happen through plasmodesmata for example because through the plasma death mata a substance can can be transported from one cell to another cell example of substance are ions for example or product of photosynthesis for example glucose can glucose are transported from one cell to another cells through the plasma des mata for example and then okay gap junction between uh animal cells allows for example ion to be transferred from one cell to another cell so getting a one by one for each one okay so plus modes mata channels that perforate plants a wall so through it water and small solutes again and sometimes proteins and also rna compass can pass from one cell to cell okay so this is where cell allow substance to pass through right so they have they have continuous uh cytoplasm okay uh where cytoplasm are adjoining cells are connected so muscle cytoplasm um continuous okay so plaster can communicate through specialized openings in the cell wall which is the plasmodesmata where cytoplasm of adjoining cells are connected and then uh the next three is for the animal uh cell uh so you have digestion that's museum and also gap junction tell [Music] because sometimes the the question can ask you to label the which one give which one is that ejection which one is this museum which one is cab junction so you have to know the structure also so for thai junction areas of tight connection where membranes of adjacent uh of adjacent cells can start areas of tight connection between membranes and cells tight connection what is the function of this type connection it is to prevent extracellular fluid from getting in between the cell so it is these are the key words prevent the cage of extracellular fluid uh substance between cells so now palestinian so this is cell one for example and this is within cell two okay so outside here you have extracellular fluid okay extra cellular fluid to prevent extra cellular fluid from getting between these two self okay so you have this type junction um and then the next one is the desmosome which is anchoring junctions so our points of attachment between cells in fasten cells together into strong sheets okay uh and then subsystems substances can still pass freely through the spaces between the plasma membrane so these are a tight junction sorry this muzzle you have protein here and the protein is anchored uh into the cytoplasm through these intermediate filaments okay so you have intermediate filament to anchor the desmosome protein okay in place and then the next one is gap junction or communicating junction so provide cytoplasmic channels between adjacent cells allows the transfer of small molecules and ions between uh between cells okay so that is cytoplasmic uh channel so it allows ion a small molecule to pass through so this is the image under um an electron microscope okay uh digestion and then you have intermediate filaments that anchors the desmosome uh in the cyto into the cytoplasm and then you have the gap junction that allows ion to pass through so kitter take two minutes of break sketchup thanks alain you against almost all right so we are going to continue with um animal uh animal tissues and also plant tissues okay specialized animal tissues and plant tissues so these are the second and two last subtopic of this chapter okay so um ccn cells undergo cell differentiation and become specialized in structure and function so it means here every cells in your body will have different structure and different function okay so unless i sell to that by the tissue and somewhere so they will have the same shape and the same function okay so cells of different tissues will have different structure and function okay so tissues are groups of cells with similar appearance and common function okay so different tissues have different structure to suit their functions so for example you have four categories of animal tissues epithelial tissues connective tissues muscle tissues and also nervous tissues so so the first one is epithelial tissues so for the epithelial tissue it covers the outside of the body and lines the organ and cavities within the body okay covers outside of the body uh so it means that your skin is also made up of epithelial tissues organ uh linings of cavity means that your digest digestive tract can digest a digestive tract starting from the esophagus the stomach the small intestine and this upper rectum and this motor aligned with epithelial tissues okay and then uh aligns the organ okay for example organ your lungs okay your lungs are also aligned with the affected tissues your lung contains for example alveolus okay so the alveolus is made up of epithelial cells okay which is very thin thin layer of cells okay that allows the diffusion of a gas all right so it contains cells that are that that are closely joined so the shape of the fetal cells may be squamous squamous it okay so the arrangement of affidavits uh epithelial cells may be simple which is one layer stratified multiple layers uh and then sodos pseudostratified it means that it only it only has one major but it seems to have many layers okay so this uh shows you uh an organism a wolf okay with uh different organs inside shown and then with different uh cells of epithelial cells or tissues okay stratified it means many layers again squamous it means that the shape of the cell is flat so this is uh it forms the uh the the lining of the oral cavity for example okay your oral cavity will have many layers of cells that are flattened in shape okay and then you have pseudostratified columnar epithelium epithelium so you have shape of the cell with varying varying height okay but it is actually one layer of cell surround yes so it is actually one layer but it seems to have many layers that is what you mean by pseudo stratified okay so stratified and then here you have simple squamous epithelium simple one layer squamous cell that are flat in shape okay so this uh for example you can find in the lining of the alveolus the wall of the alveolus in the lung and then you have next one is simple columnar epithelium which is lining the small in the intestine basically one layer of cell that is long in shape okay in the intestine and then you have a cuboidal epithelium which is the nephron within the kidney here in the nephron within the kidney is made up of cuboidal epithelium so this one as you can see it allows uh it is basically one celtic okay that allows the the the diffusion of uh water and also ions that occurs in the uh in the kidney okay for absorption and reabsorption process secretion process okay so okay so i said our cells are flat and arranged in a single layer so this allows diffusion of uh and passage of materials so where can you find airsight of lungs and a lining of blood vessels air sacs of lung is uh referring to the alveolus okay so the alveolus it must be one cell thick one layer okay this is to allow diffusion of oxygen and carbon dioxide across the alveolar wall okay and then a lining of blood vessels so you have three types of blood vessels actually you have the blood capillaries uh the arteries and the veins okay so these three blood vessels are lined with a simple squamous epithelium on the inside especially they concentrate by the blood capillaries so blood capillaries it only has what it is it is only one cell thick the wall of the blood capillaries is only one cell take why because it allows the diffusion of um gas okay across the the blood and into the cell and also it allows the diffusion of nutrients from blood into your body cells so that's why it needs to be only one cell thick for the blood capillaries three and then next is simple columnar epithelium so the large brick shaped cells okay so found where secretion or active absorption is important so you can find it in the intestine secreting digest digestive uses and also absorbing nutrients so as you know the function of the intestine it involves in the secretion of enzymes uh and about secreting secretion of enzyme the small intestine can the wall of the small intestine can secrete enzyme also to happen in the breakdown of food into its monomer so once the food is broken down into its monomer then the small intestine can absorb the nutrients across the wall and into the black vessels okay to be distributed throughout the body so that's why the intestine will have this type of cell simple columnar epithelium that involve in secretion and absorption secret enzyme absorb nutrients okay the next one uh is a simple cuboidal epithelium sodium phage and then it is specialized for secretion so secretion process occurs in the kidney all right found in kidney tubules and also many glands including thyroid glands and also salivary glands thyroid glands and also salivary glands thyroid produces hormones and the hormone is secreted into the blood salivary gland produces amylase and the amylase is secreted into your oral cavity so that's why it is composed of this type of simple cuboidal process secretion also occurs in the nephrons okay okay and then the next one is a stratified squamous epithelium so as you can see stratified is multiple layer many layers of cells okay and the opinion characteristics the characteristics of the cell is that it will regenerate rapidly okay so it says here new cells formed by division near the vessel surface the new cells are formed at the master surface here okay and then push outwards okay replacing cells that are slowed off so these are cells at the surface that that have the tendency to be slowed off why because at the surface of the tissue here it is exposed to um for example a condition that uh that that that causes the cell to be easily um upper uh slot offload the outer skin uh and lining of mouth get your mouth uh will the lining of your mouth can easily be replaced uh by by the new cells again also anus and also vagina and also actually inside your stomach okay your stomach also has what um hydrochloric acids okay so the hydrochloric acid will cause the cell at the surface to be uh easily um uh damaged and the damaged cell can be replaced by this method okay regenerate new cells and then the next one is pseudostratified so consists of single layer of cells of varying size okay so the cells of the trachea will have cilia uh and then the arrangement of the cell is pseudostratified okay columnar so be uh for other example bt cilia sweeps mucus along the surface avoid attain to the firings and enter into the uh esophagus and into the stomach to be digested and then the next one is uh okay glands okay you have to know what is what are glands so glands are specialized epithelial tissues so you have three examples here goblet cells okay three types goblet cells so what are goblet uh cells there are uni cellular exocrine glands that secrete mucus where can you find goblet cells they are found in the in the cells of lightning lining the trachea which is functioned to produce mucus to trap the contaminant please young light object goblet cells lining of the stomach okay your stomach produces hydrochloric acid which is very acidic so the acid condition causes can cause the the cells lining the stomach to be easily damaged hello okay so easily damaged okay so inside the uh you have you will have a goblet cells that secrete mucus and prevents uh the lining of the stomach from being damaged by the acid condition of the hydrochloric acid inside the stomach okay uh and then the next one is exocrine glands so as circling glands uh what does it do it secretes product through a dog onto exposed epithelial surfaces salivary glands can secrete uh amylase into ducts and then secrete it into your oral cavity if it is a face candida a top bone uh the pancreas so pancreas is another type of exocrine gland why because the pancreas uh is involved in the production of digestive enzyme okay digestive enzyme glypsine lipase uh amylase okay so this uh the the the product of the pancreas which is the enzyme uh is produced and secreted by the pancreas into a duct and enter into duodenum give and then uh the next one is endocrine glands so endocrine glands are glands that produces hormones it will get hormones into interstitial uh so in your in your brain you have a structure we call it as the hypothalamus okay so hypothalamus can secrete many enzymes so one of the story can secrete many hormones one of the hormones the pancreas will produce the gnrh and uh the the hormone will enter straight into the blood to be travel across the blood until it reaches the target organ which is the ovary so that's why endocrine will secrete the hormone straight into the blood okay today take in the transport uh via the black la okay so you need to gambala so goblet cells cellular endocrine sorry esocrine gland all right uh in this case it produces mucus and then you have the sweat gland produces fat uh into uh out uh out onto the surface of the skin and then you have parity cell salivary glass just to produce saliva okay uh that is uh amylase for example okay the next one is connective tissues binds mainly binds and supports other tissues so it is made up of three elements which is the ground substance can be fluid jelly like or solid and then the fibers and also cell fibers can be collagen and it is elastic and then um cells can be uh example fibrocytes and also blood cells so blood cells are examples of um component within within the blood uh and then the blood is uh an example of connective tissue your blood okay your blood contains many components and one of the component is blood cells another component of blood is you have plasma plasma extracellular extras extracellular matrix again in in blood okay so extracellular matrix consists of fibers embedded in brown substance okay can be frequently plasma so plasma in black is freed right okay so we need this are connective tissues so you have loose connective tissues fibrous connective tissues loose antares skin and then open your muscle and also bone okay and then uh fibrous uh connective tissues the one here shown is tendon gate tendon that connects the muscle to the bone and then you have the bone itself so exactly which is an example of connective tissues and then adipose tissue to stop fats and then cartilage okay cartilage here that connects uh that that is in between bones okay and then you have blood okay so black cases of plasma which is the extracellular matrix of blood and then the the cell of the blood you have white blood cells red blood cells and also platelets connective tissue it is most widespread it binds epithelia to underlying tissue and holds organ in place so your skin is an example of organ okay so it holds the organ your skin in place diabetes it is to hold your skin in place okay and throughout the body and then number two fibrous connective tissue then uh dance within uh with collagenous uh fibers so it made up it is made up of collagen so example if uh our our tendons okay which attach muscle the mineralized connective tissues so you have cells within the bone you uh which is osteoblast so the uh the the function of this cell is to deposit a metrics of collagen it combines also with ions such as calcium magnesium and phosphate okay to harden uh into a heart mineral matrix inside the bone and then black gay blood is also an example of connective tissues so the blood uh the extracellular matrix is the plasma okay it is in liquid form and then you have cells that are suspended in the plasma which is the red blood cells erythrocyte white blood cells and then white blood cell uh the leukocytes and also the platelets cartilage yanila okay contains uh collagenous fibers uh so it is uh strong and flexible okay so it says here uh skeletons of embryo contain cartilage and replaced by bone as the embryo the next one is adipose tissue specialized loose connective tissue that stores fat in adipose cells okay so the function is to insulate the body and and store fuel as fat molecule what does it mean by store fuel color process cellular respiration or tahoe the open your main substrate cellular respiration glucose okay so glucose cellular respiration energy in the form of atp glucose for example so your body will turn to not fat okay adipose tissue uh to be uh to be used as fuel for cellular respiration the glucose will be converted into fat and stored into adipose tissue and causes your adipose cell to expand okay so next uh is nervous tissues okay so uh the nervous tissues function to detect stimuli and transmit signal the signal in this case adela impulse transmit impulse uh from from neuron to a neuron okay and then uh the the component is the neuron cell itself the neurons or the nerve cells and then the other one is glia cells oglia okay glial cells oglia so neurons or tahoe fusilli are allowed to transmit signal impulse the component of myelin sheath allowing and then uh the the axon terminal so the external covered by myelin sheath it's abdullah before again so you have gap between the myelin sheath okay so this myelin sheath is made up of uh one type of cell we call it as schwann cell okay schwann cell uh is a type of glial cell okay so the function of schwann cell is to function as electrical insulator okay that allows the the the axon to be able to transmit impulse from nodes to nodes okay until it reaches that contaminant okay so it's intuitive it'll function as electrical insulators such as uh schwann cell okay okay so next is the muscle tissues so responsible for many types of body movement so the cell contains actin and myosin that allows the muscle to be able to contract you have three types of muscle tissues which is cardiac muscle smooth muscle and also skeletal muscle austrated muscle so cardiac muscle is the muscle of the heart smooth muscle where can you find smooth muscle you can find smooth muscle uh upper lining the digest the digestive tract that's just a digestive tract stuck there by the esophagus intestines it is lined by smooth muscle that allows this muscle to be able to contract peristalsis okay so paracelsus is smooth muscle which is the contraction is involuntary you cannot control the contraction of the muscle but the one that you can control is the skeletal muscle or people can scan skeletal muscle and you can control that is voluntary for cardiac muscle tabula you cannot control again so the the the pumping of the the heart okay so you need a position cardiac heart uh smooth muscle for example lining the the stomach okay and also skeletal muscle uh that are found in your muscle okay and then okay so cardiac muscles it says here forms the wall of the heart straightened it okay and then has a similar contractile properties and then has fibers that interconnect cell which relay signal between them so what does it mean really significant it means that the the cardiac muscle is capable capable of generating and transmitting impulse yeah because the transmission of impulse is not uh generated by neurons okay it is generated by the cardiac cells itself okay the heart muscle is the heart the heart cell itself okay the heart cells of the cardiac muscle is capable of generating and transmitting impulse and causes the heart to be able to contract and relax contract and relax okay and so this is to synchronize heart contraction structure specialized issues there's a across across upper across the cell wall until it reaches if we know it somebody reaches uh at the effects of the heart and causes the uh ventricular wall to contract um okay so so the the contraction of the heart muscle is uh is due to the transmission of impulse between the heart cells too okay all right contract pump their heart and causes the heart to contract though uh who can die by the instruction from the brain so it could open your benefit there okay benefits and then next one is and then found in walls of the digestive tract urinary bladder arteries and other internal organs calor artery is your blood vessel scan so your blood vessels can upper vasoconstrict and vasodilate concentrate and dilate okay so vasoconstriction and vasodilation are the largest only smooth muscle yoga digestive tract it's about can only contraction of smooth muscle so it means that the movement or the contraction is involuntary okay such as training of this of the stomach starting to massage the wall of the stomach will contract relaxing relax to to mix the food with the enzyme with the hcl okay so that the food is will be broken down and then constriction of arteries faster dilation and muscle constriction so next one uh the last one for the skeletal muscle adela for the massage masala okay uh sodium voluntary uh cases of bundle of lung cells and muscle fibers and then the muscle the skeletal muscle fibers formed by diffusion of many cells okay fusion of many cells resulting in nuclei in each fiber muscle fusion of many muscle cells okay so arrangement of contractile units with which is sarcomere and fibers give the cell as a striped austrated appearance so the the last one is for uh plant tissues specialized plant tissues uh so the the plant has three basic organ which is the roots okay the stem and the leaves okay so each organ is composed of three basic tissues which is the thermal the mud is outside they function as the protective uh covering and then vascular to transport the substance and then ground kick around your base basic support there okay so each tissue uh from each tissue from tissue system a system continues throughout the plant okay so caloriment outside can it is altered protective covering is uh it functions as the first line of defense massager can prevent the plant from being infected okay or by infection of pentogen for example and then for non-woody plants okay none would you plant someone a herbaceous plant okay so they have single tissue called epidemics a layer of tightly packed cell and then for woody plants they have uh the the most tissue would be the upper the the the epiderm will replace the damage again i need this one okay so in roots water and material absorb enter through the epidermis of the roots the root hair and then ensure you have guard cells so car cells um allows gaseous exchange lungs carry out photosynthesis carbon dioxide enter okay uh the by-product of the photosynthesis it releases oxygen for example okay so and then trichomes so this one is trichomes okay which is specialized epidermal cell in shoots to reduce water loss and reflect excess light so this is to uh reduce water loss i guess so the next one is vascularity system okay so this is to transport materials uh provide mechanical support uh you have two types of vascular tissue which is xylem and flour mineral parascular so asylum is to transport water and minerals again from from the soil it is absorbed through the roots and then until it reaches the they leave or tissues of the plant okay so it is made up of tricyates and also vessel elements cape tricyards and also vessel element here so flow worm is to transport sugars sugar as you know it is the product of photosynthesis so the cell of the leaf produces the sugar and needs to be transported to other parts of the of the plankton to to the stem to this to the roots to the fruits to the flower okay so it is through the flower so it is uh made up of a sieve tube so they have pores that allow substance to be transported from from one cell to another and then companion cells which is to generate energy in the form of atp in order to allow the to allow the transportation of this uh sugar okay and then the last one is crown tissue system it forms the bulk okay of the plant okay and then composed of three tissues uh you have the parenchyma calling keema as chlorine keema okay so this tissue can be differentiated from each other by the cell wall structure circular parenchyma is living okay involved in metabolic activity and they have uh primary cell walls okay so yeah so it uh you can it can carry out photosynthesis uh because they have chloroplasts and then in function as storage okay because from this chloroplast obviously it produces sugar and needs to be stored as starch okay or oil and then it also saw water and also salts okay the next secretion resin tanning hormones enzyme and sugary like so they produces all these products right and the last the second last one is parenchyma so it is leaving unevenly thick primary cell walls so they have unevenly thick primary cell wall so provide elastic support it is flexible and then found in stem surface and long long leaf veins okay examples as celery stock hello family of us flexible [Music] so the last one is clearing keema so have both primary and uh and thick secondary wall strong and hard because of extreme thickening of the secondary secondary wall though provide support for plant body so example shell of nut a walnut and also coconut okay about thick secondary wall strong and hard okay pits of cherries and peaches busy pizzas online [Music] on the sideline somewhere this uh so yes [Music] impulse to the muscle muscle reflex reflex okay uh instant energy to to be provided and causes your muscle to contract instantly foreign me attendance thank you yeah um foreign thank you okay um you