Human Anat&Physiology I (LEC) PDF
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Summary
This document details lecture notes on human anatomy and physiology, focusing on feedback mechanisms, homeostasis, anatomical terms, and body cavities. The lecture explains negative and positive feedback mechanisms, their roles in maintaining internal stability, and examples. It also describes anatomical position, directional terms, body planes, and body cavities and their associated serious membranes.
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There's a positive feedback mechanism and there's a negative feedback mechanism with a negative feedback mechanism who are causing the very little change in the direction that is opposite of the initial change which sounds kind of complicated but if I use this graph at the bottom here if y...
There's a positive feedback mechanism and there's a negative feedback mechanism with a negative feedback mechanism who are causing the very little change in the direction that is opposite of the initial change which sounds kind of complicated but if I use this graph at the bottom here if you look at the str graph right center here there is a dotted line so if the at the bottom of the page right But again that varies that changes a little bit throughout the day we are never really at 98.6° for a very long period of time instead when we generally Tennessee is what's happening with this song okay so your body temperature will drop off until it gets to a certain point at this first Arrow this first Arrow represents the bottom of the range where our body temperature can be at while still functioning normally so that is in other words the lowest our body temperature can go before our brain hits in a change when the body temperature is slow down here the brain will begin begin heat producing measures so this right here this upward slope is where you would see like a little bit of shivering Maybe Awkward until it reaches the maximum of the desired range so this second Arrow right here is the highest your body temperature can get while still functioning normally at that body temperature your brain is now going to change the response it will now promote heat loss mechanism so that would be like sweat until you go back down straight to the bottom again and then it starts so exciting just does that make maybe feedback mechanisms are really good for making small changes or small alterations to the variable to keep it ideal without being static so you kind of keep it at that like normal operational normal functional level there's also positive feedback mechanisms essentially the opposite with a negative feedback mechanism we want to make small adjustments that are spread out over long periods of time with a positive feedback mechanism we want extreme changes that usually occur only over the short period of time now when I say extreme changes for positive feedback mechanism usually people immediately assume acute increase and activity which that definitely does occur don't get me wrong but it can also mean the opposite you can also just tank and organs function or what it's doing in order to kind of get the desired effect the thing about positive versus negative feedback mechanisms the body generally doesn't like extreme changes fast changes either so therefore you know there are definitely a few really good examples of where you see positive feedback mechanisms in the human body however almost every variable in the human body is going to be controlled by a negative feedback mechanism they're just more stable and again when it comes to positive feedback mechanisms you're not looking for small adjustments you're looking for huge changes example:positive feedback mechanism: blood clotting when the skin tears open and an individual is bleeding. You want to stop that blood loss as fast as possible. A negative feedback mechanism it's going to like oh I'm going to stop bleeding a little bit but now I've done too much and I'm just leaving it again to build a clot as fast as possible and to stop that bleeding so with with a bloodline you tend to see a huge release of clotting chemicals in a very short period of time in order to get all those cells to stick to one another and actually form that clot to stop leaving and of course we have instances where homeostasis is not maintained yet - Imbalance in homeostasis-> links to disease/illness - aging-> as people age chemical reaction carried out less efficiently, structures break down, (joint tissue in arthisis breaks down) Most variables controlled by negative feedback mechanism,-> nfmh overwritten to positive-> going from small steady state to big huge changes suddenly-> disease ilness -> autoimmnue disiorders when negaitve overwepoweerred by psotiive-> perosn immnue system attacks own bodily cell(hard ot reverse) Positive (labor, blood clooting) can’t be controlled usually stop-> if extreme change the body can’t withstand it and leads to death. Anatiomcal terms: anatoimal position: ref to person referring to It's on your left but it is my right hand so you would say it's the right side of the body not the left that's something that you will have to keep very straight especially with the bones in the lab there's also directional terms which help to explain one part of the body relative to others very important again for the lecture and to the lab I'm still technically going down through these there's dorsal versus Ear lateral to eye-> ear medical to eye Describe to a patient relative to a point of origin there are some parts of the body there are some parts of the body where the point of origin is center of body there are so arms you send it out right nowme parts of the body where the point of origin is considered to be the center of the body so that midline again but not always so I'll give you a good example of where that doesn't work if I'm just talking about no other part of my body I'm just talking about my heartbut s the of my arm iso so I can save something is distal I can say something is possible if I say something is profitable I mean it is closer to my shoulder if I say something is distal anytime you hear Disco is distant so it means it's farther away so for example again if I'm using my arm as an example my wrist is pistol to my elbow there's also deep versus superficial this is describing location and reference to the surface of the body superficial means it's closer to the surface meaning if it's closer to the skin the skin is the most superficial organ of the body deep means it's farther away so like internal organs are usually visceral organs are usually called Deep organized for that reason and then there's Superior vs interior Superior is above interior is below so the head is superior to the neck the neck is interior to the head so I can do that way there's also body planes dividing the body into different regions the sagittal divides the left from the right usually anytime you're talking about you can almost always assume it's mid-satchal or something you call median the mix agile or median plane divides the body into exactly equal left and right calves the frontal playing divides the body into front and back anterior posterior but also think of this ventil dorsal and then finally there's transverse transverse divides the top of the body from the bottom in other words superior versus inferior you may have also heard a transverse cut probably called a cross section A cross section is a transverse cut these planes of reference are going to be really important for dissections for this lab you have to dissect the cheap rain and if she's high and you'll have to cut them you know you're lavish when you use one of those three terms to describe how you should see maybe that cup body cavities most organs visceral organs are found in one of the body cavities there's two broader categories with subdivisions for each the dorsal body cavity is called dorsal because it's a long again it's more like a back side of the body it's the one in yellow right here it's subdivided into the cranial cavity and the spinal cavity caprino cup cavity is the open space inside of your skull or your brain is the spinal cavity is the open spacing created by your vertebrae where your spinal cord runs through so the dorsal body cavity is kind of it's Unique to just central nervous system structures there's not much else going on there the eventual body cavity is everything in red that you see again towards the front of the body towards the ventral side of the body I listen to volume up into two main sub cavities at the top of the body there's a thoracic cavity the thoracic cavities your chest cavity this is where you find the heart the major blood vessels and the lungs and then as the ventral body cavity which houses Ab cavity-> Diaphragm 0 but> respoiriaty but sevres as ca andvities webetween that are found in these cavities they are called serous membranes a serious membrane is a double layered membrane meeting there are two layers to it which are formed because the layers of the serious membrane technically folds over on itself to create two layers the overall function of the serous membranes mostly protective your organs kind of operate independently of one another you know when your heart beats it does rub up against the lungs mostly the left lung but a little bit on the right as well each time your lungs change size from inhaling and exhaling it rubs on the surface of the heart you're abdominal public organs are all working to digest food so they can trap and they rub against one another of all of that rubbing all of that friction could potentially lead to damage friction means that structures can rub off on one another which could potentially lead to damage that's where the serious membrane's come in if the serous membranes cover all of your organs there is a sheet of tissue that prevent organs from correctly rubbing against one another so you're preventing that damage from all that movement all that shifting all of that now it's a double layer of membrane like I said it is named according to what structure it is touching there is a visceral portion and there is a parietal portion the visceral portion is the layer of the serous membrane that clings directly to the outer surface of the organ the parietal layer is the layer that claims to the body wall it helps to hold the serous members in place and also hold the organs in place as well so if I kind of give me an example here you're going to find that I like drawing things and making charts and crafts and whatever so here's a very long moms have their own serous membrane right and we have it divided between visceral and varietal visceral is again going to be the portion of the serious memory that clingsimmediately to the lung surface so it will be like literally right here all along the outside hold and goes back around the lungs to form the parietal layer so forms folds back on itself Outer space and that space is filled with something called serous fluid serous fluid has kind of an oily texture it's slippery in nature which is beneficial because again if the organs are moving and they're surrounded by the serosa then that technically means it's a Rosa are also constantly moving and rubbing together as well but serious fluid prevents the visceral and parietal layers from essentially abrading one or the other away Parietal but we can also name these layers according to what organ they are associated with so first there's a pair of cardium the pericardium is the serous layer layers of the heart so there's a visceral pericardium there's a parietal pericardium surrounding the heart Flora are the serious players of the lungs again each lung has its own serous membrane for kind of helping to isolate structures the heart and each of the lungs are are kind of isolated from one another with these serosa which is really good because you don't want disease anywhere in the body but you really don't want to season the heart of the lungs so by having them essentially formed individual Chambers it helps with prevent the spread of disease from one part to another okay if the left lungs here the right one is protected to a certain extent by its own serous membranes so forming those individual Chambers to help prevent that threat and I thought there's a peritoneum current Liam are the serous membranes for any of the organs in the abdominal pelvic cavity are we just kind of group them together but there are visceral and brile - - Action items Aug 22, 2024 | Human Anat&Physiology I (LEC) - LH 008 - The human body secrets ad creates cream some of the dozens of different substances most of them are considered to be mixtures also when you're talking about mixtures of different type of metrics you know they can be solid or liquid or gas but in the human body most of the mixtures tend to be liquid or fluid in nature so when you're talking about a mixture so when you're talking about a make sure you're talking about any substance containing two or one sure you're talking about any substance conven ri mixed to everything there cre I'll the - a solution is has two different components there's a solvation of solute the solvent is the dissolving medium generally speaking solvents tend to be in Greater amounts in a solution Center in the last class - Universal solvent of the human body water since mosrt of our body ismade up of this. is the substance the molecules whatever you may talking about you maybe talk about that's dissolved in the solvent so in a solution relatively small in size and also they are smaller in amount compared to the solvent for the most part Solutions one they're homogeneous and nature meaning that the solutes is consistently distributed through the solvent is kind of evenly spread out again they do exist a solid liquids and gases with the human body will usually just consider themselves something about the volume do not settle out meaning they don't like close to the bottom of the solution they remain suspended saline nhpl install this is important in medicine because if you have an individual and the hospital needs to have an ID IV fluids are saline solution and they are very precisely measured because saline solution can have potentially very dramatic effects on the shape and function of body cells when you're talking about Solutions again that concentration is going to be important you can describe a couple of different ways next weekend lab is going to actually be doing example problems with percent solution and molarity so I'm just briefly mentioning them here for set solution is the amount of solute dissolved expressing percentage of the total volume of the solution so like I said I'd be doing my normal ID fluid it's 9% NaCl nine grams of water for 100 mils or I'm sorry 9 frames of salt for 100 mL of water and then there's also molarity the number of all this multiple substance per meter of solution remember the mole of any element or compound is equal to its molecular weight it's total molecular weight so glucose glucose has a molecular weight of 180.156 therefore you have 180.156 grams of glucose per mole two other types of mixtures that you see in the human body there are the colloids collides are headphones or not consistent through-. Nto env theel they disturbi minted -> particle larger in size-> particles larger in size and do not settle out-> colloids can be found inside of the cell - Fluid portion of intracellular portion-> cysto(mostly water) suspends ions floating, large size proteins, cell organelles that remains suspended and doesn’t sink to bottom of cell. - Colloids undergo sol- gel transformation. Fluid cell portion can change its own consistency. Can go from more fluid to solid this - Cystol can undergo cell transformation - depends if cell is dividing or not- when the cell divides cystol go to more fluid state so things can move more easily - Suspension more heterogeneous with large particles diff from colloids will if left sitting-> suspension is blood-> nonliving fluid portion (plasma), 3 cell types suspended in blood- light blood, cells, white blood and platers, ansf transport protein carried by blood from one part of the body to the next. Individual with heart pumping particles remains suspended. If you take someone’s blood and put it in somewhere the plasma remains at the top and the rest of the stuff at the bottom. - Chemical reaction-> normal physiology process is producing/breaking/converting form 1 sub to another-> chemical bonds are stored chemical energy and reactions occur when those bonds are made/broken/rearranged. Lots of diff reactions but fit into the synthesis reaction-> involve formation of bonds between smaller individual subunits 2 create more complex molecules. All anabolic reactions are synthesis. Also endergenoic not spontaneous require energy to take place. Decomposition taking complex molecules and breaking down into smaller less complicated part , so breaking bonds, catabolic reactions are decomposition-> reactions can e exergonic/endo but one is humans body be exergonic in nature so spontaneous and not a log energy required for this kind of reaction to take place. - exergonic/ endergonic talking about energy/spon not heat. Require organic/inorganic substances to happen. - Inorganic: water (makes up most of human mass 60%) of total body water content-> found in cells-> universal solvent-> used to transfer substances(repsiortart gase,s nutrients, repsoritary waste->transports well in water allows it to arrive to destination faster-> disposed of more efficiently. Water is important for transport substances that need to be transported from 1 body to another with a charge associated (tend ot 2 be on reactive side)-> don’t want these particles reacting with smth on their way to way to destination-> wrapped in - charged particles take - negative protein put in bubble of water which prevents - charged protein from interacting with anything around it then removed once the protein reaches its generation. - , chemical reactions in solvent, some chemical reactions produce/use water, used - Water has a high heat capacity->total amount of heat a substance must be absorbed by a substance to raise own temperature by 1*C. - Water has highest heat capacity, absorb massive amount of heat to raise temperature by 1*C. Water absorb large amount of heat to increase own temperature water is preventing huge shifts in internally body temperature, preventing sudden decreases which can throw off bodily functions, so easier to maintain 98*6 and preventing it from switching or changing to high. - Since most fluids are water based, good for protection, good for cushioning the body and organs. Hit to body/blow water takes the hit so not transferred to internal organs so do not take that damage. - Heat of vaporization of water is high->Amt of heat a water must absorb to break bonds to go from liquid to vapor - Heat of vaporization is important for sweating and body cooling. Sweat glands active produce and create more sweat on surface of skin. Sweat mostly water which absorbs heat. Sweat has to absorb a large amount of heat to evaporate/vaporize from the surface. Prevents overheating. Internally body temperature from getting to high.water reactive since some chemical reactions use water-> the one uses water is a hydrolysis reaction - Hydrolysis reaction->adding water to compound to break bonds AB+H20-> A_H + B-OH add water to this and splits AB reverse is called dehydration reaction here you remove water to form bonds -> a lot of body process fat digestion-> to bring food you eat throughout the day break down larger molecules into smaller subunits this is a hydrolysis reaction otherwise nothing you consume would pass your inteninse to build into your bloodstream, once it enters bloodstream cause dehydration to rebuild these Salt forms electrotypes in solution-> aware of iron elector types found in red blood cells, iron binds to oxygen in lung tissue, oxygen is then transported to other body parts where cells use it for ATP Production. Sodium and potassium important for generating electrical impulses. Done by muscle tissue cells and nerve impulses-> contributes to excitability-> without NA And K muscle cells will not be able to contract as they should. Acid and bases also electrotypes-> hydrogen and hyderlo xl play a role in PH. Acids release hydrogen in solution causing decrease in PH. bases release hydrogalaxy causing higher PH. 7.2-7.4 is optimal blood PH Optimal PH blood-> within this range b/c chemical reactions occur within this range If blood PH drops too low/high chemical reactions either stop entirely or proceed at a rate that no longer sustains life. This blood PH drugs can throw it off, people with heartburn that take tums, eating spicy foods so the body has to adapt and have a way to fix this using buffers , higher/low can disrupt cellular activity + chemical reactions inside the cell. When the PH is thrown off the body starts 2 using a buffer weak acid/base that releases some H+ ions but not all. Weak acids used when Phh blood become too basic to release a few Hydrogen ions to bring PH to normal level. When it comes to weak bases a weak base will be used to tie up free hydrogen ions in solution, by tying up hydrogen ions neutralizing them so no contributing to the blood PH. use a weak base when blood becomes too acidic, pick up some H+ ions, use of the weak base causes increase in PH. buffer use do not prevent PH changes entirely, have a PH change when use buffer but not as significant, small shift but not smth the body can’t handle Organic compounds- all organic because they contain carbon atoms, carbon is useful for electornetural forms covalent bonds neither gains nor loses electrons so shares evenly. Carbon is useful in organic compound b/c when carbon forms bonds with other atoms/molecules can form diff shapes, diff shape which changes degree of function, some organic molecules that form changes in carbon, long fibers chain good for parts of body that need to be held together really well b=have long carbon molecules b/c tough, ring shapes in protein , in lipids in DNAring carbon molecule. - 3 major organic: carbohydrates, proteins, fats large complex molecules made of individual subunits called monomers - Carbohydrates: sugar + starches: monomer for this is massachur: to create large carbohydrate take mononessa and bonding them together: galactose (in milik, dairy) fructose (found if fruits), glucose the monosaccharides the body wants + uses- the monosaccharide a monomer used for ATP production. Can’t use fructose and galactose directly for ATP. the human liver is taking fructose + galactose converting it to glucose and releasing it to blood, in some way to use fructose + galactose and use it if short on glucose. To form large more complex monosaccccc have 2 link them together. Dishachar tend to be smaller, polydachchairdes several monosaccharides linked together largest and most complex of carbohydrate together. - Can’t use diss and poly for energy production b/c too large too complex-> polysaccharides used for covering externally body cell series of polysaccharides, diff polysaccharides they produce that attach to outside of cells, useful for immune system identity what belongs to use vs what doesn’t belong to use. Poly helpful in your body recognizing your own body cells speed it up this process vs smith act can destroy your immune system - lipids -> three major typesL triglycerides, monomer of triglyceride fatty acids and glycerol. - - tri: saturated fats (single bonds, packed tightly together) b/c molecule so packed so tightly saturated fats tend to be solid at room temperature– consume on regular basis but general suggestion mad ebay medicine higher vs lower amount, lower intake of saturated fat—> saturated fat solid at room temp and in your body, if you consume a lot of saturated stick to inside of blood vessel walls blocks off a large portion of blood vessel decreases blood flow. If blood vessel that supply heart disease heart no longer getting oxygen and + nutrients they need, if don’t get oxygen and nutrients they need heart stops beating, - Unsaturated-> spread farther apart in molecule, take more fluid nature, liquid at room temperature, thicker than water, unsaturated consume this in higher amount, unsaturated found mostly in plant base( avocado, peanuts, olive oil) - - , trans fat, - hydrogen added to site of double bonds, solid in nature, hydrogen added to double bonds, mostly unhealthy in all the fats (cookies, cakes , deep fried food) - omega 3-fatty acids– more fluid form of fats found in cold water fish, salmon, find krill (trim like animals), generally the healthiest of the fats - Functions of triglycerides-> triglycerides stored in fat tissue if not used and benefits, tissue sitting under our skin protection fat can absorb shock, physical trauma atompost tissue can absorb shock so not transferred to internal organs. This atompost tissue is also insulation so used in maintaining internal body temperature, prevents excessive heat temperature. - - If an individual is short on glucose, the body can use monogluei and fatty acid for ATP production to easily access energy sources. Glucose is the preferred b/c they produce more than the other stuff phospholipids-> modified triglycerides into a shape, 2 fatty acid hydrophobic-> fatty acids tails do not want to be near water do not want to be near water, also a phosphate head is hydrophilic doesn’t mind being near water. Polar phosphate heads come into contact with wtae rnad nothing will happen that won't react with it. The plasma of our cell is a phospholipid bilayer two layers. Diff steroids in humans body-> cholesterol most important-> two sources through the diet (meat, egg, cheese), can produce liver can produce choolsterla we need, your liver produces 85% of total glucose you need per day so whatever cholesterol your body needs so this means 15% of cholesterol needs to come in through the diet.liver still produces 85% even if consume cholesterol. If eating too much cholesterol hardens blood vessels. Major function cholestorol used to produce other types of steroids, testosterone/estrogen those require cholesterol to be produced, hormone produced help body deal with stressful situations (corticosteroids) and require cholesterol to be produced. Cholesterol important b/c worked in structure of plasma membrane helps to strengthen it. Without cholesterol, cells would rip open and be opened a lot more easily. Then the proteins-> monomers: amino acids and each protein has a specific amino acid sequence that contributes to its structure. Structure also determines function in it’s. proteins diff shape , proteins of diff functions. Protein fibrous protein, long strands of protein that link together to form long strands are difficult to break can be pulled/stretched/ return to their original length after pulling/stretching it. Fibrous proteins in parts of body that frequently can pulled/mushed. Collagen is in connective tissue, especially the skin has to be able to move and stretch collagen gives toughness to skin. Also found in muscle tissues, when they contract have to return to original shape to prevent tearing, found in ligaments and tendon. Tendon attaches muscle to bone, helps with movement, ligaments attaches another bone to bone helping to keep skeleton together. Globular protein-> more spherical ins shape,more compact less long than fibrous protein, more chemically active, more structurally important: good transport molecules( transport a lipid based substance in the blood,(lipids + water don’t mix) to make lipid double in water has 2 get bound to some type of transport protein. Immune defense proteins serve as warning signal letting cells know disease + to protect themselves + times where protein can kill of a pathogen. Regulation of growth/development ensuring body cells are dividing when they should be and stop when they should be. enzymes are biological catalyst (lower activation energy of chemical reaction), enzymes are extreme specialists one reaction they catalyze do nothing else, some other enzymes generalized catalyzed a few different reactions so not as specific. Enzymes have to the use of these enzymes, lowering of activation energy for chemical reaction to take place without the use of enzymes and lowering activation energy either chemical reaction won’t happen at all or will happen so slowly the person will die before it’s so slowly. Enzyme by speeding up reactions ensuring we are carry out these reactions in the right time ATP transporting molecules of every body cell. And can carry out specialized tasks. ATP gliosis, krebs cycle and electron transport chain(produces the most requires availability of oxygen), but glycolysis and krebs cycle not enough to keep cell alive and needs glucose Glucose not used directly for cell to produce energy but ATP is energy of cell Adenosis triphophospate Three on each ATP molecule these high energy phosphate tail, high bond (unstable– ATP molecule more stable by getting rid of one of those tails) happening with energy production Enzyme requires ATP to carry out function, ATP transfers one of tail temporary, while attached ot phophstae tail, as soon as pohopshate tail breaks enzymes will do nothing until gets another adenosine triphophopsate , enzyme getting ATP transferring phosphate tails for enzyme to be energized for. If ATP what body cells use to perform speicalized function but to keep themselves limited storage reserved for storing ATP. much ATP as cells needs at one time and no more. So if have a cell receives a message, needs to increase activity, more of a particular type of substance, more energy , more ATP but no longer needs to carry out function so produces as much as ATP as eeded to sustain basic life functions. More active more ATP, less active less ATP. stored enegry is wasted energy b/c takes ATP 2 produce ATP. Transport protein inside the cell that requires ATP, outside to inside, transproto protein important for reuquring from oen part of cell to another, muscle cells no lonegr able =, electrical impulses no longer able, without oxygen can’t produce ATP cel can’t carry out it’s most basic life functions. Can also use glycerol and fatty acids, proteins body breaks down it’s need for surrival Very function the importance that it plays with our various physiological properties of what consistently carrying out so first of all when it comes to the cell actually when it comes to science and medicine in general besides the medicine has the general tendency to use less or briefcase prefixes and suffixes with their terminology if you know this terminology and I'll give you three pieces and stuff with this corrupt the next two semesters to be competitive learning along if you understand please what they mean the last origin you can identify joke about anything in the body by location if not by specific function or specific structure so when you were talking about the cell if you see the prefix cytosis So remember the cytoplasm is the gel light internal fluid that suspends proteins ions organelles and other things such as all is the fluid portion the water base of the cytoplasm there's also a suffix c y t e anytime you see cyde it's talking about specific type of cell a lymphocytes is a particular type of cell that you find in the immune system this is another example and remember different types of cells and the body have not only different micro Anatomy than you look different from one another that also means that they're going to function differently from one another as well Salon sells are going to have a few common functions every single body cell can produce ATP from certain exte alln and if you have a functions like that that's generally butt and if you have a functions like that that's generally but tend light sustaining functions-> but since cells loks diff that Cells shape_> im[rotsnt for disgustinghing diff cell typeSo again if you have cells that have across the board the same function then they'll all have the organelles that are needed for that for example mitochondria for AC production also have that but depending on the individualized functioning so we're going to have the individual depending on the individualized functioning so we're going to have the middle test of organelles in order for example there are some cells in the lining of your stomach that produced and release need toof cunton thatle test of organelles in order for example there are some cells in the lining of your stomach special organnel to do that other body parts htat produce HCL don’t need it. When it comes to celular function is Disrupted this can and does lead to death and funciton. Severeity depends on how many cells are being disprute.d if several cells not dong hwat they should be dooing body ca get away form that, if most of ht ecells in tissue or organs problems. Blanket functions they all do- blanket structure they all have, boundayrt forming mesmbrane at the microsphic level- plasma. Human body has memberans has slectivley perimtable (soem substances cna leave, but some substances don’t cross plasma membranes stay where theu are locked in). Cytoplasm internal fluid, cystol fluid base mostly water but also have ions, protein, organells which can be more specialized or function. Sthen nucleus which contains all genetic information, which code for protein that contain specific functions. Almost all of our body cells have a nucleus but not all of them do a couple of examples of cells where you do not find a nucleus one is going to be your red blood cells mature functional red blood cells do not have a nucleus at all another example is another type of blood cell called a platelets which are used for blood clotting there are more specific reasons why neither of them have a nucleus but in general it's not really necessary it's not super important for either of those blood cells to have a nucleus because their lifetime is relatively short lived we are constantly producing blood platelets and red blood cells like literally we produce hundreds of millions of them per day at a minimum the red blood cell only been three to four months a blood platelet 10 days at most so maybe you're mean it's getting rid of them putting in more remembrance Drive instructor the pl Two different parts Ppla,sma membrane descibed by fluid mosaic model, fluid created by phospliid bilayer-> two layers of phospholipids aggregated together , fluid quality, phospholipids bilayer so thin fluid in nature. This provides benefit by having phospholipids bilaye rby havign fluid nature to it, makes plasma memebrane more flexible, cells can stretch with tearing. Mosaic comes from protein dispersed htorughout the membrane, b/c liek around half b/c proteins large in size. Dispersed throughout phospholipid bilayer, some anchored in place, stuck for their lifetime, others can float through it, can carry out indivudalized function, important boudnayr forming structure at separate intracecellular fluid found inside form extraceullar fluid outside the cell, contains cytoplasm so it’s functional, fluid mosaic created by chemical composition both structural and functional. - Lipids: phoploshiplods form basic strcuture most of the area of the plasma membrane. Phospholipids bilayer created by two layer of pholphids which is modified tri-glyericide. Arrangement of phoplside, phosphate heads in contact with interceullar fluid so have to point outwards, fatty acids tails have to point inwards towards oone another, this arrnagement exists b/c phoppshate heads polar so can be in contact with water. Interceullar and extracellular fluid both intraceulalr fluid, fatty acids tials point inwards towards each other b/c hydrophobic don’t want to touch water at all. So not in contact with either type of water based fluid. This arrangement having hydrophilic on inside and hydrophobic on outside. Tiemn where cells ssutains minor amount of damae. Tear in plasma membrane, cells stretch too far those fatty acids tails (since hate water) come back together to get away from the water. Having fatty acids hating wtaer meaning small tears cells can fix. Save us time + enegry - Lipid based substance important for structural : cholesterol: phospholipids bilpayerr creates if random stiff into plasma membrane this cholesterol increase strcturla integrity of plasma membrane. This reduces likelihood of plasma membrane tearing as easily. Also helps to contribute to size and shape. Lipids strcutuallt important, proteins functionally important, plasma membranes proteins help carry out specalized functions-> group classify by their location relative to cell membrane, integral proteins( integrated into membrane- found the plasma membrane) some proteins transmembrane proteins(span entire width of plasma membrane, travel from one side to another, from itnraceullar fluid to extracellular fluid) some are open, channel trvalering down center. But down to right some without a open channel. Some integral proteins that do not span the entire width, more on the inside than outside. Transport proteins (if wat to transport smth form one side to another has to carry proteins form wone side to another, receptor proteins integral functions. ) - Perhipearal protein: perhipey not imbedded within the cell membrane. Usually with peripheral attached ot intracellular especially inter-membrane proteins. And again some major functions enzymes are proteins are one type of protein function I don't go over to in depth or technically transport proteins so they help you move substances especially on the inside of the cell cell attachment function - 6 major functions plasma proteins :transport protein ,carrier protein, motor proteins ( all responsible for transport)- (transport substance across cell membrane), ( diff memchanims to transport subsyances across-tube straight through it- channel protein) this channel protein always open j b/c empty channel through transport protein doens’t mean anything can go through it, selective in substances transport depending on type of protein, some trapsort protein that specifically transport water, some proteins for movement across membrane, a lot of selceltiyvley based on size, channel smaller or greater dependgn onmoleucle, some charged base some will only transder + or -, some transport protein need ATP to move substance(ACtive transport)-pumps. Sodium potassium ATP pump, require ATP to make transfer between inside and outside of cell, active proteins pumps undergo confrimational change in order 2 transport substances protein has to change shape. Receptor protein bind to certain chemical, initiate change, recpetor bind to homonore-homonore protein. Most hormones don’t enter cell at all, initiate change through cell but don’t enter cell, bind to receptor protein, when receptor protein binds to hormone, homorne changes shape, change in shape is what initiates all of the changes inside of the cell, effects some hormone off turning cell of or preventing it from doing these. Receptor protein different degree of speicficty, some bind to only one cheimcal messenger , some receptor proteins have ot bind to multiple chemical messager ot initiate change in protein, so some are more generalized. E\ Enzymes vary in specificity degree- can carry out one reaction alone, some enzymes involved in different steps for the same reaction, how much of reaction enzymes complete(some enzymes carry out complete reaction from start to finish alone-> carry out simple reactions ex: simple conversion, small arrangement in molecule) ,-- some reactions more complex- more enzymes wth each enzyme carrying own individual steps. Enzymes act cooperatively Cell- to cell recognition proteins, allowing our bodies cells to idenity and recongize one another, plasma membrane of 1 cell at top and , thsi bottom has green dots attached to it (hydrocabron chain0 glycoprotein), at top larger protein cell-2 cell recognition protein- recognition protein bands to glycoprotein temporlaity and uses strcture of glycoprotein to identity if it belonds to body or no. different body cells that can carry out dfiferen types of protein. Body cells uses glycorptoein to identity our own body cells vs one don’t belong to us- immune system cells. Can tell body vs non-body, every idnivdual produces glycoprotein chain that’s individual to us. Attac Attachment protein help to hold other protein in place. Soem proteins anchored by attachment protein in place. Blue strand coming off attachment proteins. Anchors membrane in place othe times membrane proteins contribute to strcturue of cells, help to hold the clel in place, or help to give cell some shape. Interceullar junctions-proteins used to attached nebighoring cells , attachment protein time vary in time remain attached mot other protein especially ones involved in itnerceullar movement. Other proteins bound 2 one another for long time, important for keeping tissues together, tissues aggrarvation of cells of similar functions so want to keep these together to attach them by interculal rjunctions. Carbohydrates are : extraceullar surface of our body cells dotted with cabrohdyrates, some attached to glypolciids, we have carbohydrates shell surround our body cell. Every one of body cell has a sugar-coating glycocalyx. Eevry indifudal produces one glyplax. Not only immune cells sort out self vs not self cells can sort out one type of tissue cells from another type of tissue cell by using glycalyx, important for immune system, major function, minor function for carbohydrate sugar coating on the stiffer side similar 2 shel sort of contributes to cell membrane structures prevents it from being torn too easily. Interceullar junctions; attach nebihgoirng cells to eahc other, want to keep cells of similar function to one another. These cellular juncitons temporary or permanent depdning on use. Tight junctions; blue grey , all purple dots make up tight junction. Tight junction basically riveting two cells together. Tight juncitons not only tend ot be permanent, also impermutable, no substances passes between two cells joined by a tight junction. (long rivet strands that extend the entire). Found in type of bodies where don’t want htings moving, inner most stomach lining, cells in inner msot lining cells produce hydrocholric cells, average PH of human acidic 1.3-3 (really acidic), cells make up lining cells joined by tight juncitons to prevent hydrocholroci acid from leaking. If HCl leaks corrde stomach and all internal organs Demosomes: anchroign junctions that extend from 1 cell surface to another. (blue grey sheets cell membranes of nebighoring cells) cellular veclor, two sides of veclor interlock prevent from pulling apart. Interlockign joined togtehe rby cadherins, interlock on nebihgoring cells from one another sewed together liek velcro. Stick tow cells to another with cadherins need associate structure ot hold cahdeirn in place called plaque and keratin filaments. (cadherins imbedded in plaque , plaque imbedded in plasma membrane of each cell._ also have to hold plaque in place, by keratin filaments found inside the cell.) the plaque and keratin filaments if get rid of either stablizie desomoems, travel apart from one another, cells won’t adhere to one another as well. This particular type of cell junction passage of material. -mostly likely to find demosmes where parts of body pulled/streched shearing forces. Demomses in human body skin, skin needs flexbility , demomses used to attach nebighoring cells togtehe preeventing them moving apart each tiem you use a body part. Gap junctions; protein orange structure nebighoring cell membrane, each gap junction channel travelring straight down middle, notice gap junctions connec tto one anotehr channcel line up evenyl between 2 cells, forming perfect tube from one cell to anojter. These particular proteins called communication junctions, itnercuellar fluid from 1 cell to the next , these proteins selective (charged or sized depdent) , ion exhcnage nebighoring cells exchange ions thorugh this gap junction(take what them or there nebighoring junction need), psychological Membrane passport movement of substances into and out of the cell. - Three major functions: all body cells obtain substances to carry out most basic functions, glucose + oxyegn entering the cell for ATP to produce. 2. Disposal o waste, chemical reactions occur inside of the clel which produce nitrogen bases or CO2 so cells have to get rid of this b4 it kills them off. 3. Celsl have indiudal substances, many cells produce substances need ot go elsewhere, have ot pump it out of the cell, cells in endocrine release hormones that travel to other parts of body. - Movement is determined by if energy is required - Passive movement transport: don’t require ATP down concertaiton gradient, substance moves from high substance ot a low concentration: high solute ot low solute movement, diffusion 1 driving force kinetic energy of molecule ( how often molecule collide).- more often collide faster diffusion happens. - - Kinetic energy influenced: concertation a solution which a high concentration particles wil be closed packed closely together (more freuqnely they collide which leads to a faster rate of diffusion.), molecular size size of solutes that is diffusing, large size molecules have lower KE, smaller moelcuels have higher KE, - Larger size molecules travel more slowly, collide less frequently, diffusion is relatively slow - Smaller size substance, higher KE, travel around faster , collide frueently with one another, which is why smaller size molecules tend to diffuse faster. - Temperature: affects rate of diffusion, temperature influences KE, colder temp decrease KE of molecule regardless of size leading to slower diffusion rates. Higher temperature mean smoelcules colliding faster which means they have higher diffusion rates. - 3 Passive transport: Simple diffusion: is when a substance can directly cross plasma membrane on own, no movement required for substance to cross through phopohlsiid bilayer (limits to what can diffuse through phospholipid bilayer) Simpe dufSubstances pass through simpe diffusion small in size (b/c don’t want big gaps)like repsiortary gases (Oxygen and carbon dioxide), something else substance can directly cross bilayer whether it is polar or non-polar.non-polar are fat soublute water substance are polar souuble, so fatty acids Non-polar: steriod homornes has to enteer cell to exteert any change in ceullar acitibty, produced with cholesterol type of fat/lipid, everything fat souble paasses htorugh unless big , fatty acid tail fine with contact with pilar Facilted diffusion: no ATP but use of protein. Transported something large in size or something is water soluble. When it comes to the use of the protein different proteins with different mechinas to transport. - Carrier mediated protein: transmembrane proteins, specific to large size molecule that are transported: - carrir use mediated protein-to transport substance the protein has to change shape (open + close on one end, change inshape is what allows it to push through)) - Carrier mediated protein temopoirlay bind to whatever they are transporting. Carrier mediated protein usually a limited number of binding sites ot whatever substance transporting. This protein has 1 site meaning can only transport one molecule across membrane at a time. So proteins can 4 or 5 but this limits the amount of substance being passed at one time. Only pass usbatnce is binding sites available. Channel mediated: open channel extends entire length of protein from extracellular surface to itnercullear surface, channcels water filled so transport water substances. And even if protein has channel down the middle, idndidual mediated channel selected soem highly selective by transporting only one protein. Membrane protein that transport just water. Transmembrane mediated protein allowing potassiumto cross the membrane, these channel mediated protein leaky or gated, where they have a door on either side. Leaky: Channel that extends through, nothing to close it on either side b/c constantly opened, whatever substance it transport to leak through. Gated have at least 1 door on either side; so can close protein to tempolriary prevent transport. Want ot move substance and want it to stop so use a gated substance. Usually gated substance need ot bind to a hormone or smth to reopen. If a gated osmosis : specific diffusion to movement of water across plasma membrane, plasma membrane selectively permeable some substances allowed to cross including water (some substances cna’t cross leaving locked in/out), infleunes water movmeents loves to follow solute determines water movement in body is solute concentration. Water moves from a low solute concentration to high solute concentration. Water movement continue in 1 direction until both sides at equal concentration (equibirum reached) equal side of water , water can go thorugh phopolsipid bilayer Aquaropins:Some body parts where water movement has to happen fast and a lot of it and aquarions is a channel protein Water movement : osmolairy: total number of solute particles in a solution (solution with more solute has greater osmolaritry), cocered with osmolairty solute influence water movement, diff solute concentration in diff parts of body water goes to diff places, so we say that water displaces solute. Movement across plasma membrane: pressure that describe outward cs inward movement of water. Water moves by osmosis until hydrostatic pressure: is pressure of water against (pushing up against) inner wall of plasma membrane -> thsi forces water out of the cell-> if hydrostatic pressure high enough pushes water outside of the cell) (pushes water out of cell) Osmotic pressure- inner pressure of water ot be drawn or pushed back into cell (determined by soltue concertaiton), pushes water back in cell If hydrostatic pressure=osmtoic pressure equal exchange of water across membrane, so no net movement of water in or out. but if pressure not equal cells might change size and shape, Diffusion occurs thorguh freely permeable membrane.( Two solutions at equilibrium, same volume equal osmolarity, equal volume because of freely permeable membrane, the solute and water will balance each other out perfectly on either side. ) have changes in size/shape of cell by changing water volume in and out of the cell, membrane selectiley permeable solutes allowed to stay where they are. Water loves to follow solute, so water goes from high to low concentration. Diffusion still takes place and these two solutions will no longer reach equilibrium but these 2 solutions are at same volume. If change solution of cell changes water leaving in and out o f cell-> toniciity Tonciciity: a change of water movement imbalance in osmosis ( more water leaving/entering cell) so changes size of cell - Only describes solution hypertonic(higher solute concertation inside of cell, water follows solute so if more solute outside the cell water will leave cell-> when water leaves cell-> shrivels up crenate ) , hypotonic(less solute concentration then the interceullar fluid, so water will enter, filling cell with water so swells up can swell up to this point of bursting lyse - isotonic(same tonicity, same solute conceration as the inside of the cell, equal water exchange of plasma membrane, so no change in cell size and shape) never the cell - ability of a cell to change size and shape of a cell by alternating internal volume - Interceullar fluid- tightly regulated by kidneys at 300 mOsm, this is the concentration of inside of body cells. Isotonic Simple difsuon not only small size 8/29 Passive forms transport- require no energy required, transport protein may/may not be used. Depends on which type of passive transport which depends on molecules used. ( move from high to low concentration active transport- always require use of transport protein when moving , requires ATP , energy is required for energy mechinams to take place - Energy required to move substance across plasma membrane, molecules too large, charge(- negatively charged particle), water soluble - Celsl use active transport 2 move thigns across memerbane substance is moving from a low concentration to a high concentration, across concertation gradient. Molecules do not like to be in high concentration areas ( b/c don’t like to be in tightly packed areas) so use high concentration to force them where we want them ot be. - - active transport: moving substances across concentration gradient, from low to high concentration ( inside or outside the cell). - Transport protein and active transport forms called pumps. Primary active transport + secondary active transport-> ATP required for both - Difference in the way the ATP is used. Primary active transport- transport protein need phosphate tail ( needs ATp required to move substance), take 1 of 3 phopshjate tails from ATP break it off transfer it to pump, chanzges shape (which allows from transport form one side to the other side), several different pumps to move substances - Sodium Potassium ATPpase- enzyme requires ATP needs a phosphate tail to move- often moving sodium potassium , a specific # of ions in different directions, always pumps sodium outside cell, sodium always going ot be pumped into extracellular fluid - On other protein side, 2 binding sites for potassium (+ charged ion) potassium moves in opposite direction. (potassium pumped to inside of cell with sodium potassium ATppase)-> this leads to imbalance in concentration of ions, sodium higher conc than inside, potassium higher concentration inside the cell than outside-> difference in concentration called a gradient, -> ion gradient created is important exctiabliy of responsive of body cells- true for neurons and muscle tissue cells - Secondary active transport energy is sditll required: transport protein used does not require phosphate tail.( doesn’t use ATP or phosphate), is considered active b/c SAT uses gradient created in primary to move a substance. Primary active transport stops secondary active transport also stops. - SAT to pump glucose in2 cell has 2 pumps sodium into it, fi sodium potassium ATpase pump sotps working no longer bringing sodium into cell , if no longer cell inside the cell body is no longer prodcuign ATP - AT transporting two different substances(cotransport), some transport protein act as symporter transport protein transports 2 substances in the same direction, (both enter or both leave cell). Sodium and glucose both pumped into the cell( symporter example). - antiporter-> transport substances in opposite directions,(1 substance pumped into cell and 1 substance is pumped into out of cell) - Uniporter- only transport 1 substance across membrane Vesicular transport: also requires ATP- involves formation of vescile Vesicles membrane sack (made up of membrane) and taking something large in size/ negaitvley charged (don’t want it interacting) and packing it up and transporting it elsewhere. Endocyotis: forming vesicle to bring substance into cell Exo- forming vescile ot remove/expel something from a cell Transcytosis: substance outside cell bringing it in transporting throug cell to other cell and pushing out-moving across cell (uses both endo and exo in short time period), good 4 allowing material to pass thorugh (tight junction don’t allow material to move between cell so move from 1 side ot antoher) Vesicular trafficking- movement of some substance from one part of the cell to another part of same cell (so nothing leaving or entering) ( proteins, smaller organells moved this way) Endocytosis: forming a veshcile to bring something in the cell ( so susbtanc emoves form extraceulalr fluid to intracellular fluid), all veshciles made of plasma membrane so material comes into contact with plasma membrane which folds in and then seals at top which forms veschiles Phagocytosis: forming veschie (phagosome) (so sitl made up of plasma membrane) specific tends to be solid, debrib that needs to be disposed of, important 4 immune function, pathogen function to destory using phagocytosis.once debri/pathoogen completely sealed off phago specific destination in inside of cell- travel to lyssome which produce digestive enzyme lysome exposed to digestive enzyme: break down solid material into smaller pieces so can be desotyred somewhere else ○ Immune system: can engulf pathogens, infections, ecan kill organelsl so longer infeciton and cna no longer infect body clels Pinocytisos: (not specific) veshciles formed during pincoytsis smaller than other ones formed, plasma membrane randomly folding in and taking in small amount of extraceulla fluid to inside of cell, beneficial to body cell, pincoytosis tells cell abt external environment (extraceullar fluid). Ion concertaiton/water content information of extracellular fluid transmitted to inside of clel so cells can make adjustments. ○ If cells is infected by pathogen, give off chemical and when other bodies see this cheimcal process- produce things to avoid taking pathogen in Recpetor meidated endocytosiso: specific receptor protein when nebhgoring proteins fold in form veschiles. Things brought in Tends to be smaller than pinocutpso ○ Smaller number of substances boruhgt in destroyed, this process brings in substance the cell wants in higher concertation, binds to veschiles brings it in, substance can be distributed throughout the cell, Endo- taking away from plasma membrane Exoctoyss: Secretory veschiles- expelling material from cell to extracellular fluid ○ Secretory veschiles- lot of secretions released from cells thai way , hormones produced by endocrine cells, neurotransmitters released by a neuron this way, neurotransmitter releases fuses with plasma membrane and closes off almost immediately. Msuucs secretion, salvia any body fluid a cell makes, and waste can be disposed of faster than trying 2 use transport protien ○ All veshcules made from plasma membrane, replenishses plasma membrane b/c exo form a vewschile on inside of cell. Travel to inside of plasma membrane, fuse with it then dump the plasma out Membrane potential Sodium higher concertaiton outside, potassium higher concentration inside which creates a gradient. Difference in ion concentration on either membrane size, different of charged particles on either side of the particle, creates a potential(voltage) every body cell has electrical charge associated with it. Most concerned with nervous tissue cells( neurons) and muscle tissues cells. All of cells have - charged associated. When all of cells doing nothing, so when msucle cell not contracting asnd neurous not firing messages around even when doing nothing has a resting membrane potential so sitll has a charge associated with it even when doing nothing. Cells - charge, outside of body cell more positively charged, inside of body cells more negaitbley charged, inside of cell more negative so resting memrbnse potential is - Extracellular fluid sodium found in greater concentration outside the cell. The sodium in extra cellular fluid stays since can’t move freely. There is a consistent flow of potassium from the inside of the cell to the outside of the cell.sodium found in greater concentration outside cell. In intercellular fluid, potassium is the primarily ion. Embedded in plasma membrane, leaky Embeeded in plasma membrane, leaky potassium channels don’t have doors (relative free flow of potassium from interceullar to extracellular fluid, as potassium leaves , leave behind large negitvlaey charged protein, normal resting membrane average of xxx, body cells want to maintain that number, so not only created with that number but also keeping that number, if chage resting membrane potential change hwo responsive how quickly a cell responds to it’s enviroment, so actually comes to maintaining that resting membrane potential keeping it at x millivolts , concerned with sodium potassium ATppase, primary active transport , taking K that left cell through leaky potassium channels and pumping it back in) By pumping that small amount of potassium back in with ATPpase pump maintaining electronegative gradient, difference in ion concentration. Potassium most important for creating and resting positive. When comes to resting membrane potential Sodium locked out of cell so doesn’t do anything. - Concerned with sodium when change resting membrane potential, allows our nervous cells to have message and send it somewhere else, so that’s when we are concerned with change sodium - Body cell bring in substances to allow our bodies ot know hwat is happerning in extraceullar , need 2 communicate with each other, and external environments, but if cells know what’s going on around them can change their own activity level to help maintain homeostasis balance in their tissue. Communication between cell neeed proteins receptor cell, chemicals like neurotransmitters need receptor protein in order for that converstaiton to take place Plasma membrane receptors: - Integral embeeded in the membrane - some of receptors are inc harge of contact signaling: communication between nebighoring cells, receptor protein for contact on nebighoring protein and allows cells to talk to other cells Helping body recngoze iimmunue body cells vs non-immnue body cells - Help body cells recongized infected body cell to protect - Normal cellular development (growth) cells determine if they can grow in size, divide based on amount of other cells in contact with - So if have cell bound to other surrounding cells this indicate tissue packed with cells- don’t want to grow, so cells surrounded other by cells won’t physical increase in size on it’s own and won’t divide/reproduce. So if have cells not bound to a lot of other cells surrounding it (empty space around cells) , cell is free to grow(promtoe growth). Cell can either increase in size on own or can produce to make more daughter cells - Some receptor protein renpsible for chemical signialing; uses cheimcial to communicate change to inside of cell( chemical binds 2 receptor protein. chemical messenger(ligand) , ligand for chemical messenger(ex: ions, hormones ,( chemical binding ot receptor protein). - Overall process : G-protein coupled receptor:most general pathway ligand binds to receptor protein (ligand) causing receptor protein change shape acitivates a protein to a G-protein. After G-protein activated binds to a 2nd integral protein an effector protein(carries out a resnpose) effector protein activated by G-protein,produces a 2nd messanger ( some type of molecule)- - 2nd emssnager -subsyance produced by effector protein- 2nd messenger function to activate or deactivate enzymes on inside of the cell, once kinase enzyme activtaed carry out a specific reaction leading to a large amount of some substance. Beneficial to body cell: energy saving mechanism (G-prtoein) b/c one ligand binding at start, at the end creating large product amounts. To produce whatever don’t wnt 2 produce a lot of it b/c leads to large amoitn being produced ( - Ligand : diffenret types of cell have different receptor protein that bind to same ligand: - Same ligand can bind 2 different body cells and have different cell; (what type of enzymes does it produce, ex: insulin effect of increasing uptake by cells), either type of ligands and bodies can do more thigs( simualtory) or can slow down acitivty dpeneding on the receptor protein, ligand protein can have the same effect. - Chemical signaling happens Tissues- Nervous Tissue(sending and receiving messages to various parts of body(to regulate and contorl diff type of body functions, receiving info about other parts of body and telling cells what they should be doing) Musle tissue- movement of other body parts which can be voluntiary/involutiary 2 cell type found in nevrous/tissue good at excibaility/responviness Epithaeltial tissue: Connective tissue: Tissues are aggravation of cells, organs made up of at least 2 different types of tissues, with more speci. Tissue formation benefical b/c of specialized b/c idnviudal tissue types can carry out, can carry out body complex functions. - Drawback: related to disease if indivudal has disease (can be genetic, acuqired in lifetime, or acquired by pathogen) or if indivudal has homostais imbalance htat wipes out one of the the cell types-> wiping out one cell type in tissue can no longer - carry out what’s needed. ->some type of problem won’t be deadly but other types of tissues Eptiehtal tissue: most is a covering tissue: - Boudnayr fomring tissue covering organs 2 separate them from one another Conencitve : support used to hold other parts of bdy togther, holds organs together preventing them from coming apart easily Nervous tissue: Neuron good at changing resting potential: good at changing own voltage that electrical impulse is created. (message is) - Supporting cells: nonconducting cells(don’t produce electrical impulses that neurons do, don’t send or receive messages, support neurons to hold neurons in place, physicoally wrap around neurons to protect or insulate the neurons, allow neurons to gain neutrons, ions, oxygen, dispose of waste products that they need in order ot survive, Muscle tissue that allows for movement of various body parts ( can control when muscle tissue contract so other nervous system body controls it) - Specialized organells (microfilaments) Actin and mysoin interaction allows muscle tissue to contract - Muscle tissue - - skeletal muscle tissue (voluntialry type of tissue control their own cell to muscle tissue, how much force ,can contract) - Cells have striped appearance(striations) that sketcal muscle tissue have. In order 4 skeletal muscle function to move body parts has to attach to bones. Muscle attaches to bones through tendons.every time sketlal muscle contract pulls on the bones. Skeletal msucle tissue needs smth solid ot push/ pull on i=on to generate movement. - Skeleton to contract muscle needed to move Cardinal Muscle tissue _> found only in heart muscle, cardiac muscle have strations but involuntary don’t control how forcefully heart or often heart beats( parts of brains that do this autmocially) Smooth muscle tissue: (no striations) found in all walls of hollow organs (except heart) like urinary bldder, disgetive organs, reproducitve organs, -> involuntialry don’t control - Hwo frequently/forcefully good at control itself - Determining contraction of smooth muscle tissue how full(more stuff,-.> going to contract more freuqerntly and forcefully) the organ is Specailzied: Epthailieal found in all body parts Epithelial tissue boundary forming tissue :seperates one body part from another body part but when substances have to pass. Any substance given from 1 part of the body has to pass through any body part has to pass through eptihetial tissue to get through. - Two forms f eptithetial tissue Covering eptihetilum: boundary forming eptihailim, internally separates one body part form another, outside separates our body from external environment, all hollow organs have covering epthium on their inner most surface. Glandaur eptiheiulm: makes up different body glands All features epthiulm layers: Apical surface polarity: determines which side of body is in ocnatct with conrtective tissue Lumenempty space on inside of organ (ex: body travels through lumen for organs) b/c lumen empty space “free surface” d Microvilli0- plasma membrane extension from epithelial cell( to leave or enter the cell ahs to move through cell membrane, more cell membrane you have more substance to pass- microvilli is for) increase surafce of cell by adding extra plasma membrane so transports substances through epitheital (in small intense cells responsible for absoring nutrients from digestive tract into bloodstream) Cilla- tiny hairlike projections that come off form aplical surface that move. As cilla beat back and forth create current in the movement that is used to move substances. Basal surface as a non-ceullar adhesive sheet, sticky + holds epythiteal sheet in place, preventing it for moving or shifting - A basal lamina, a filter in basal surface that determines what can or cna’t enter basal surface from underlying tissue - Use interceullar junctions for epthiteal sheets - Tight junctions (riveting cells together-aprt of body don’t want material passing between cells) - demomoes : good for preventing cells from pulling apart(mechincal stress) - Dsome epthtietal tissue have both types- Epithelial layers hope to hel them in place with basal surface Basement membrane - basal side - working w/ interceullar junctions(physcially lock cells together) but basmeent membrane reinforces them and prevents the mechanical stress , forms true boydanry btwn connective tissue and other part Epthitela basal lamina part of basal layer to reinforce sheet Reticular lamina part of connective tissue- has fibers to strength it. Contincous fibrous retricular fibers with fibers in connective tissue All epthetial layers: - Avascular no direct supply to epitheilum - Still need oxygen/nutrins/need to dispose of wate- so b/c no blood supply use diffusion to do this with underlying connection tissue (b/c underlying conencitve tissue has blood supply) - Innerveted- supplied with nerve fibers and allwos brain to recivee info about epthieal High capacity 4 regeneration: covering eptheital (has lots of friction, abrasive) so cells tend to get destroyed or restored. Epthieal cells regenerate damage cells so no loss of function with epthiteal. - Skin flakes off and cells from environmental factors so repleinsh eptiheital layers to help esmnure these work Classify by thickness(layrrs of cells in eptihteal Simple layers- single layer of cells in epthital(lower of # of layers, faster the things that get passed form epthiteal is(b/c usually passing from point A to pint B) - Absorption, filtration,secretion Stratified- eptitheal with 2 layers of cell - Seen where abrasion/friction most common - Multiple layers of cells prevents from using epthital tissue in short time period. Even though eptheial have high capacity regeneration cells cna be rubbed off faster than regeneration can happen, so have multiple cell layers Squomous- thin, cubidoal - dimensions more equal to one another Columnar cells- column shaped (more taller than wide) Simple squamous eptihtiulm- very thin which qallows substances 2 get passed in very faster Uses: absorption, filtration, secretion - Found in lung tissue ( oxygen + Co2 across urface of lungs, faster respiratory gases move better to prevent waste buildup, lining of lungs where gas exhchange happens imple squous SImpe squaous given specific names - Mesotheilium: serous membranes ( visceral peridcaium, peritnoeum) simple layers of squamous cells. Important for keeping serous memrbanes thin sheet so don’t affect funciton. Serous membrane separated by serous fluid (so don’t slide against each other) - Endothelium: inner most lining of blood cells, make slick/slippery important for blood flow - Since inner of blood slippery blood flows easier thorugh cardiovadcular system(less work heart has to do) Simple cuboidal epitheiulium: mostly absorption, and secretion - Thicker so movement is less fast - Tends to form rings, ex: simle cubodial epthieulm in kidney tubles (filter blood, remove/add toxins to blood) - Ovary surface im[prtant for horomoen release Simple columnar epithelium: absorption and secretion - Cell shape modification to surface with the columnar cells (tend to have microvilli or cilla- - digestive tract to increase absorption in the blood - Bronci important for gas exchange - Fallion tubes have - Internal uterus part also have this cell type Psudeostraifited columnar membrane- nuclei displaced Only 1 layer of cells since every cell has contact with basement membrane When tall cells damaged, short cells grow in size to replace them. - In repsitorary tract, cilla to move debris out of lungs - Male ducts: repducitve system - Ducts of larger glands Stratified squamous epithelium:found more freuqnrltly b/c multiple layers protective without being thick enough too ruin function:(apical cells most likely to get rubbed off so cells closer to th ebasal side reproduces what gets lose) - Used for protective, found where abrasion is frequent so regenrative capacity is high - Regenerative from bottom( to apyical surface - Epthieulm no blood supply so get needs form diffusion: if straifed too thick dead b/c diffusion can’t happen so cells die b/c can’t get nutrients needed - Linngs of mouth, passage of solid waste, epidermis, (outermost layer of skin) tends to rub off Stratified columnar + cuboidal epithelium: - If large of large cell types, epithelium gets oto big for anything too function, ducts of sweat glands relatively large in size., mammary glands , columnar Columnar- only 1 layer of cell si column shape, layer of cell closer to lumen, Basal cells more cuboidal in shape to decrease the thickness of the eptiethulim, tends to be found in male urethra, upper region of throat, some ducts in larger glands Transitional epithelium: looks a mess of cells, multiple layers so true stratified eptiheliu layers, but shape of cells doesn’t follow any rules Found in inner most lining of urinary organs which are tubes conenct kidneys to the bladder Human bladder changes size/shape throughout the day-> thetranstional epithelium no rules so change size/shape with bladder so changes size/shape with the bladder throughout the day but ensures that can return to it’s original size after the day Glandular eptihelum: indivudal cells that produce secret specific products Serecetion: tends to be liquid(made mostly of water of volume of secretion) - Although secretion althoug mostly made of watr whasr makes them individual is the proteins and everyhting added to it after like proteins, ion makes up cell types Glands: the location released, the cell numbers used to make up the glands endocrine glands-NOT GLANDULAR EPTHEIULM - Do not have any ducts so not glandular epehtiulm - Collection fo cells used to release a cell that uses as the Mode of release exoocytosis which is then placed into the bloodstream without a duct - Used to release/make hormones to bloodstream - Travels elsewhere after being released into bloodstream Most endocrine form a collection of cells that make either same type/similar type of homornoes Endocrine diffuse organs- individual cells that can be scattered throughout the body or in different parts of the body Exocrine glands- glandular eptieium - Require gland use since released onto surface. tube released from glands to surface - Ex: sweat glands produces through ducts to empty out on surface of skin Can have uniceullar - release things through exocyotiss without a duct, diffuse in nature, individual cell sctatered through the wall of a cell - Goblet cels: found in lining stomach - Mucus cells: produce musuc in repsiroarty - Globet and Musucus both produce mucin that when combined with water creates mucus. - ex:mucus coats inside of sromach to prevent inside of stomach preventog ot from blocking lungd to ensure gas exchange cna take place Multiceullar exorocrine glands require the duct, need duct to go onto surface Ex:exocrine glands: human liver, pancreas, salivayr glands, oil glands - Mutliceullar- have acinus : the specifc unit of a cell that makes the secretion(so liek with mucus) - The duct(empty tube) to allow serecetion to go through acinus to the correct release surface Different classification: by structure + ways that it gets of release Simple vs compound: only care abt duct branching - Compound endcoire glads greater is size and structure and means it branches at least one - Tubular vs alvweolar(rounder) Mode of secretion: - mecorcrine glands- make secretion into veschiles passage up then Exocytosis via acini - Holocrine glands: don’t use exocytosis: acini cells product secretion as it builds on inside of cell until cell rips open and replaced later by a diff cell (ex:oil glands produce and release oil to skin surface so the skin surface do not dry out) - Aporcine glands: don’t use exocytosis, producing substance/secretion building/building on inside of cell, cell membrane tears open but doens’t rip in half, tiny little tear in the membrane. As soon as enough of stuff released, plasma membrane will restich it up.( so partially repaired, cell can fix it) ex: (mammarry glands-produce breast/milk so wouldn’t be mght be but not deteriiiend unsure if they Connective tissue: widespread and found everywhere of all tissues. The amount depends on the organ. In skin and muscle tissue more conencitve tissue, the central nervous system and brain lack of this (to send message to the body brain has to make a electrical impulse so no conencitve tissue since it would hinder the ability to send and communicate) so lack - All have extracellular matrix- helps with tissues found in cell - All tissues come from the same embryonic cell during development-> thai specific embryonic tissue is called messiac Connective tissue: All have extracellular matrix and maasai The extracellular matrix has the ground substance(the fluid portion of connective tissue The fluid portion is extraceullar fluid-> interisstal fluid, water based. Interstitial fluid is so diffusion through tissue happens, living tissues throughout cell that need to expel of waste to enter/leave the cell pass through interstitial fluid Cell-adhesion protein that help/attach living cell tissue to help these living cell tissue in their place in the interstitial fluid. proteogloYCANS: protein core with polysacchrdige attachment (extraceullar protein) - Contirbute to consisteny to ground substance (more fluid/thick(viscous))-> more proteholoycasn in ground substance the thicker the ground tissue will be - A lot of protegloycans much more solid than others types Extraceullar matrix non-living; fibers which long linked strands of protein - Strcually important use to hold conenctvie tissue preventing it from being damaged - Collagen fibers: made of the protein collagen,(the collagen link up end 2 end to form a long strand).when fiber is formed randomly crossed links with the surrounding collagen fibers. - The thickness and the cross-link with nerbighoring fibers-> difficult to break strong, resist pulling forces. Strong and flexible. Collagen fibers often found in skin(to be strong), muscle and bones(tendons and ligaments- prevents muscle form being pulled away from a close bone) Elastic fibers also made of protein chains called elastin protein. Elastic fibers strethy. Important can stretch without breaking and can return to original length after the stretch happens, this makes sure certain body parts do not get stretched out. Found in skin, lungs (when breathing lungs stretch in (to accept oxygen coming in) and then breath out) since both of these are frequently streched. Respiration hard on exhaling, lungs would not be able to remove air without this. retciular fibers: shorter than the other fibers and thin, branch a lot (spider web) through tissue, supportive, continuous with collagen fibers,(reticular lamina has rectangular fibers used ot hold epitheital sheet in place), reticular fibers used to connect or hold two separate body parts together. Homeostasis imbalance: marfan syndrome: affects connective tissue developing and the way it’s function, genetic disorder that affects body tissue. Genetic mutation in a gene in FBN1(under normal cir-> coodes for fibrillin-> improtant for elastic fibers to form). People with this marfan produce a elastic fibers that are not as elastic as normal - loose flexibility and strongness. Considered multisystemic affecting severals body system since elastic tissue is found everywhere. More elastic fibers tissue is more affected than one without. - Respiratory tracts affected (people with marfan since elastic ifbers loose elastic unable to bring in air/dispose of the co2) - Eyes/vision- lens of eye suspended in the middle by fibers. Lens used to focus light. People with this are unable - cardiovascular/bllod vessel and arties, the aorta. Every time heart beats the aorta stretches out to make sure every time heart beats aorta expands then empties blood to return to normal size. Enlarged for people with marfan, permentaly larger the aorta, stretched aorta wall thinner with time increase the risk of the aorta rupturing. If aorta rupture person will bleed out. - bones/joint- fibers including elastic to allow for mobility, without the elastic fibers don’t return to their normal size, so people with amrfan tend ot have long fingers, toes, hands and toes. Deformation of skeleton people with marfan can move their joins but dislocate. - Chest plate sternum, ppl with this have eithersternum poke out or sternum inwards making it push up against heart and lungs. Cells are the living part of connective tissue.mature/immature cells - If cell ends with blast-> immature cell type - Immature cell type: mitotic (making more cell that are specific to the tissues) - Immature blast cell produce ground substances and proteins needed to make fibers. Blast cells making the tissue. - Some cell type of connective tissue end in cyte. Mature cell type - cyte cell respobule to maintain nebgihroing conencitve tissue that immediately surrouunds them. Can communicate cyte with blast clels to produce the right amount fo fibers, to maintain the right amotn of connective tissue structural integrity. Connecitve tissue proper: any connective tissue not blood, bone or caritlalge - Loose connective tissue: fibers present in cell spread far apart making loose empty space. - Loose areola tissue: Loose empty tissue, most common of connective tissue propeller, fibers produced by fibroblast. Help to hold other parts body together to hodl different tissues and organs together. - Nourishes: cell found in areolar , due to the large empty diffusion happens. Loose areolar connective tissue white blodo cell can monitor and travel through the tissue but not part of. Due to all thsi itntersistral fluid empty space a lot of water,ions, can be stored in the intersital fluid(empty space.)\ - A lot of ground substance between fibers and cell: loose areolare conencirve lots of thicker b/c of protecglocyan(contribute to ground sub tissue) thicker in cocnsitency b/c of that Adipose tissue: fat tissue - adipocyte - store large volume of triglyerics (triglyerics cna be used for ATP produciton when body is short on glucose). So fast easy energy soruce). Quick metabloic rate a triglyerics , fat tissue using trigylerics and replacing it with what you eat. - In adipose the white space: adipose entirely lipids composed, so white space made of triglyerics (takes nucleus and shoves ot cell side b/c so fill) - Most subcutonaneous-> located underneath skin surface - Body fat %- people same size/height, all adults of roughyl adipose how much lipids is being stored. Peopel with higher body fat % have more triglyercious - Just underneaht skin surface, most organs have fat tissue assoicated not a problem until too much of fat tissue around organs. This imppairs the funciton fo adipose Reticular conenctive tissue: has reticular fibers - Formed stroma( blood cell support hold in place). - Not as widespread comapred to other forms. Usually in blood cells, like lymphones (improtant 4 immnue system so support white blood cell in place), spleen (where red and old dying red destroyed). - Seen in bone marrow where all blood cells develop/start (blood latees, red and white blood cells develop in bone marrow) so stroma is in bone marrow to ensure they develop coreectlty and to hold in place Dense connective tissue: fiber cells packed tighetly together (not a lot of ground substance, v - Dense regular connective tissue: chief cell is fibroplast that lay down collagen fibers. All collagen fibers go acorss from left ro right. All collagen fibers in the same direction. b/c collagen fibers packed tighyl together benefits sinc emore fibers contributes to the strength. Dense regular tissue : can pull tissue b4 it breaks, if fibers all in the same direction dense regular tissue can also be pullied in one direction means if pull in wrong direction these fibers are more likely to break Found in Tendons attach muscles to bones( the achilles tendon, ligaments (attach one body 2 a different bone) Aponeuroses flat sheet tendons Dense irregular connective tissxsue: collagen fibers here thicker even when compared with dense regular conective tissue due ot thicker collagen fibers - In this tissue, the collagen fibers go in several different directions, dense irregular tissue can be pulled in different directions without running the risk of breaking - Found in parts of body frequently pulled in multiple directions, (skin) Elastic connective tissue: lot of elastic fibers - leading to tissue that cna stretch and return to normal size and shape meaning lungs have a lot of conencitve tissue Chondro-> somehow relevant to carillage Cartilage- made of chondroblats/chondorcyte - Ground substance packed with progloyeans and different proteins, so conencitve tissue type cartilage stiffest type.can bend less than other conencitve tissue types Cartilage no blood supply - avascular , thin sheet so diffusion cna supply to all the cells, no nervous cell, The chondorblasts/chondorcyte get the nutrinets from diffusion Cartilage three major types: Hyaline cartialge(most abundant cartilage of 3 types)- cells spread farther apart, can bend it (firm), found in end of nose , trachea, Elastic cartilage: most flexible, found in body parts where strength and flexibility(outer ear-can twist it and goes back to normal shape) Fibrocartialge(cells and fibers really packed tightly very little ground substance)- arrangement of cells and fibers. Cell and fibers rotate through cartillage leading to a dense packing of fibers and cell is and tighyl packed of fibers can withstand a lot of mechanical stress like pressure. Can push fibrocartialeg in body parts where pressure or weight barring is common. Osseous tissue(bone) – bones compared to cartigalge/proper bone is hard (ex:skeleton) , bone is hard. the fibers in bone inorganic calcium salt phosphate sticks to fibers leading to fibers loosing mobile bendable making this harder. - innerveated - nervous system supply to the bones - Highly vascularized- lots of blood supply to bones (osteoblats/osteocytes). Bone marrow inside of cell is where blood cells is produced. If boen marorw made inside of bones, need blood supply to get to cardivassuclar. From the bone marrow in skeelton, dfifnerne tblod cells arise Blood is considered a tissue since it coves from mesenchyme. Erythrocytes most common. ( other things smaller). Plasma proteins,w ater based. Blood is connective tissue present with fibers, fibers not evident in cardiovadulcar unless damaged blood vessles. Fibers in blood are souble. Nesscary to stop bleeding. Important in undamaged blood vessles, proteins remain soulbule. Blood cells would get stuck in fibers so thsi would sotp blood flow altogether so fibers have to be soubule (unless blood clot formation) so blood cna go through. - Major blood function is transport: cardivadcualr is transport system - Tissue type: simple organs made of epithelial tissue and connective to form covering and lining membranes. - Cutaenous covering for skin. The skin largest human body organ. Outermost portion made of stratified squamous epithelium kertainzied. The outermost layer exposed to external enviroemtn so kertanizied makes the skin tough,kertain(so kills it before it gets sick) makes outermost laye rof skin dry. Pathogens and microorganisms /bacteria are not able to survive on dry skin- so prevents it Mucous membrane: lining body cavities(so example the mouth lining is mucous membrane, if hole) lead into/out of body, tend to secrete subtance so not dry. To be attached with a lamina propia ( areolar connective tissue special type). Big function of mucpsu membrane secretion, stomach liningn absorb nutrients and costal membrane of small intestine Serous membranes: line closed body cavities so no hole into or out of the cavity. Serous membrane either by what they are attached to or where the ar efound. Simple membrane with cells that produce and secret serous membrane that prevents parietal and visceral from rubbing against one another. Human body good at preventing tissue , musucs in lung tissue to prevent debris from escpaing Small injuries highly localized reponse: inflammatory response only occur immedialtey where infection/injury happened.Regentration- For minor repairs surrodunign tissue cells can divide to fill in where the gap happened For more serve infections the immnue system is needed since greater pathogen entry to body. Larger injuries damage greater tissue bodily amounts. Less likely that surorudnign tiseues can fill in the gap. Since normal body cells can’t complete regneraiton on their own so scar tissue formation(fibrosis). Bleeding occurs with larger infection and requires blood clotting (stop blood loss). Fibrosis sealing off larger damaged areas. 1- inflammation Broken blood vessels release inflammoatry chemicals- cause surroduning non-damaged blood vessles to increase in diamater(dilate) to increase blood flow to the area. Blood flow used to build in certain protein/blood type for repair to occur. Blood flow increase bring in blood clotting proteins rto stop blood loss. Brings white blood cell to areas, cut in skin easier for pathogen/bacteria to enter so white blood celsl go at the point of entry to prevent things form getting in. When inflammaiton :if cut skin then area surroudnng it is red in color since increase in blood flow, and puffy since increase in fluid to the skin - Portion of clot at the surface, that clot part exposed to dry area around it. Forms a scab, this scab also dry to help to prevent infection and sealing off wound to prevent further blood loss or damage Organzation lay down repair foundations. Increase in blood supply to damaged skin parts. All of this body supply is due to granular tissue. Gradnular tissue brings in more blood vessles which brings in more blood to. Grandular tissue brings in fibroblasts which lay down fibers. These fibers bridge from one injury end ot another to prevent further destruction. Grandular tissue brings in maxarophage that specialize in mworisoai. Skin damage from injury get in the way of repair so macorphages get in the way of repair. So anything that blocks repair is destroyed. Surface epehtiulm cells divide to replace to cover underlying fibrous area. Everyhting above is new eptheiulm. everyhting under is sealed off b//c of new eptheiulm so no longer need scab and scab can natrually detach frin scab on their own. When scab falls on new surface eptiehulm, underneath fibers that run undeneath skin, chunks of collagen fibers holding tissue. Fibers strands contract to pull damaged area even tigther. Scar formation fibrous area underneath the skin. Scar tissue Cancer: - In healthy tissue body, set number of times to divide before stops divison. Cancerous cells divide off as many times- unregulated growth, cells located close to one another form neoplasm. - Neoplasm is a tumor. Either benign(harmless)- benign neoplasm slow growing, compact cells of neolasm, isolated, neoplasms don’t spread throughout tissues or malignant Malignant tissues found in cells metastatic. Some cells of metastatic tumor cna break free from tumor and travel to dfiferent part of body can implant itself there. Uncontrolled regulated almost due to genetic mutation, if these genes are mutated cell no longer has it’s things tellign to do Proto- Oncogenes- normal/healthy genes that tell cells when and how to divide. Problem sensitive to mutation, once it mutator it becomes a oncogenes. No way of regulating cell-dvision Tumor suppressor genes if mutated, Common cancer forms:Tumor, vape pen, radiation, or ultraviolent radiation from the sun, Chronic viral infection (heptasis B and C)- can lead to cancer Chronic HEV increases risk of surgical cancer Chronic tissue can lead to mutations altering DNA IBS/Chron’s tissue constant flame up increasing risk of developing colon cancer. Skin cancer most common form and colon cancer common, Chemo and radation want to kill neoplasm cells. Cheimcals will kill cancerous cells and kill of multi-bodu cells. People wuth ch Chapter 5: Integument: Structrually important, outermost covering protecting body from external environment. - Function: proprection skin is tough/skin which makes it hard for bacteria and other microorganisms tend to not be able to surivvie on these kind of cells. - Sweat that goes onto the skin is acidic and kills bacteria since have a hard tiem surviving in acidic - Oil on skin-> kills bacteria - Melanin- dark colored polymain released by cells. Dark color is able ot asbrobrd Ultraviolet radiation this then makes sure your DNA cells can’t mutuate - Different immunye stsem cells type: dendritic cells: found in dermis (which is in integument), stop things passing into the body - Macrophages: larger pathogens and can also be important for clearing debris soo can’t cause infection or for fix. Temperature regulation on skin: Sweat:(absorbs heat and evoprates which removes heat) sensible perspiration: producing sweat to skin surface and can feel. Can maintain to internal temperature, sweat more removing more heat. Prevent large scale body temperature changes Insensible perspiration: Need this for small body changes. the sweat released to the body when doing nothing Blood suplply to control bodily heat: water absorbs heat and blood is watery and warm since blood absorbs heat. Heat goes from high to low. Blood vessles in skin decrease in size (less blood gets sent to the skin) so unable to loose heat if no exhcnage between blood so body temoertaure doens’t change. So insteasd this blood is sent to the visceral organs to prevent heat loss with the extneral enviroment. When body temperature is too warm, external termaptrues increase and blood vessles increase making blood so the blood gets blown off so this can be sent to external enviroment for heat ot sent off. Sensation: exetrocrecptors: receptors that respond to stiumuli that are outside of body (external environment) - Mechanorecpotrs- respond to touch like mechinas - Thermo: no temperature of environment - Noicetpors: receptors responsible for damage in body-> pain - Metablic functions: the skin gets vitiam C production from the sun. Viticam C is important so calcium can get absorbed from the digestive system. Calcium in opsphate tissue makes skeleton it’s skeeltoal, and calcium for neurotransmitters release Blood supply that goes to integuemtn: blood resorviors skin because the skin is 5% of blood supply and this can be changed by your internal body temperature. Skin- sweat on skin surface has nitrogenous waste like urea, ammonia this helps to reduce waste. Nitrogens waste majority is removed via the peing system Skin: Integuemtn layers - Most superficial(outermost layer): epidermis: strafiied squamous epthelium: epithelium asvacular, no blood supply to the epidermis. Dermis: thicker than epidermis and the majority of the epidermis is made up of the dermis. The dermis is made up of connective tissue and asvcular , blood supply to supply body. - Inside of dermis: adipose tissue in dermis is hypodermis: NOT PART OF INTEFGUMENT = composed of adipose tissue: energy storage for glucose needed for ATP produciton, protective to absorb shock and prevent force from internal organs absorbing shock. Insulating so cruical for lots