what is hematopoiesis so this is probably our first nerdy word of this chapter so he motto or heme means blood boy means to make so this literally means the making of blood so this is a general term that's talking about making all of our all of our blood so red blood cells white blood cells and the platelets then we have a wreath row poises which arethe row coming from erythrocytes the red blood cells and poi meaning to make is focusing just on making the red blood cells so what causes all of this what is the stimulus for making a wreath recites if we're making 206 billion a day this is obviously a pretty big deal so this involves a hormone so I didn't put this with the endocrine system because let's face it we had enough hormones with this chapter and so we'll add other hormones and other chapters as we need them so this is one that I just didn't do before so this guy comes from your kidney this is a hormone erythropoietin so the hormones name at least tells me what it does so a wreath row red blood cell boy means to make so your kidneys are going to send this hormone out the liver helps with red blood cells to a certain extent as well but the kidneys are what kind of triggered this to happen so if the kidney cells become hypoxic that means the kidney cells are deprived of oxygen the kidney cells don't care why they're deprived of oxygen they just want their oxygen so they don't realize that you can become hypoxic for a lot of reasons right say if you're getting over a cold or the pneumonia if I'm having bronchitis or some other lung issue I'm not going to be breathing and bringing that oxygen in like my body's used to so the blood that's getting to my kidneys is going to be slightly hypoxic again the kidney cells don't care why they're hypoxic so the kidney cells don't care oh you have a head cold or bronchitis they just go where the hell's my oxygen high altitudes if you've ever been to the mountains I've been lucky enough to travel quite a bit and when like you go to Norway the air is different because the altitude is so high or if you go to Colorado you step off the plane and you feel like you're starting to pant almost because you're breathing a lot deeper because the air is thinner the air in Denver or Norway doesn't have as much oxygen in it as close to sea level sea level where we're at in Danville so again your kidneys are getting deprived of oxygen they don't realize you're on vacation they don't care they're just like where the hell's my oxygen if you start exercising good for you if you go from being a couch potato which is me to all of a sudden working out every day you're gonna have a higher demand for oxygen because your muscles are trying to keep up again depriving your kidneys of oxygen but they don't really care maybe you hemorrhaged maybe you had a blood loss from an accident or for some reason your livers destroying too many red blood cells and your spleen is destroying too many red blood cells or say you donated blood and so you lost a pint of red blood cells your kidneys are going to become hypoxic so the kidneys don't care but there's lots of reasons why your blood could be carrying less oxygen than usual but the end game is exactly the same the kidneys are going to release this hormone because they're gonna try to get you to make more red blood cells so you can inject a wreath ro coin and people do and it increases your blood volume you go from 45% roughly to about 65% red blood cells which sounds really good in theory because if you have more red blood cells you have more oxygen you can make more ATP ATP you'll have you know more energy but the price we pay is the Bloods already viscous the Bloods already thick and your heart's already pumping pretty hard well imagine now your blood is 65% sick that's kind of like trying to suck down a really thick milkshake it's like takes more effort right it's harder on the body so could lead to a stroke or a heart attack so it's not all what it's cracked up to be so the kidneys have to be happy the kidneys have to get their oxygen and if they're not then they're going to encourage your body to make more red blood cells so this is why after you get over a cold which I'm still kind of getting over a cold right now but if you've had a cold for like two or three weeks or if you've had breathing issues I had bronchitis once for over two months I felt like ass on a cracker for two months once I finally got over that bronchitis for about two weeks I felt like a friggin rockstar that's because as soon as I started breathing normal I had all those extra red blood cells that my kidneys had made when they were I popped hypoxic carrying oxygen for me now as soon as your oxygen levels return to normal your body will realize you have too many red blood cells and will target them for destruction so that kind of superhero effect after you get over being sick doesn't last forever same thing with if you travel to high altitudes like if you were to live in Colorado for a few years and then come down to sea level your body when you're in collar would make a lot of extra red blood cells since the air so thin when you came back to Danville you would be able to carry more oxygen for a couple of weeks again feeling like a rock star so this is why when the Olympics is in the mountains we always send our Olympic teams out there like several months ahead to train because otherwise they won't have their there whatever their natural abilities are will be affected by the fact that there's less oxygen in that environment where does blood come from well it comes from your bone marrow and all blood cells whether talking red or white and technically the platelets even though they're technically not cells are all begin beginning as these common stem cells so stem cells are cells that really haven't chosen what they're gonna be when they grow up so they can still become anything so fetal stem cells are a lot more powerful than adult stem cells we have adult stem cells it's kind of a bad name because as soon as you're born you have adult stem cells which seems strange that a one-day-old baby would have adult anything right so fetal cells are the stem cells that can become anything so when after fertilization when we're just a ball of cells for the first few weeks every single one of those cells has the potential to become any cell in the body so this is a very powerful thing and research has shown us that if I take a fetal stem cell and I put it in my brain it becomes a brain cell so a lot of stem cells are like teenage girls like when teenage girls are in groups they like mimic the group they're with and so their personality changes and you know ladies we do this their personality changes depending on what group they're hanging out with so fetal stem cells are almost magical in the fact that they will mimic the tissue that you put them with so if you inject them into a heart they become heart tissue so the medical like implications for stem cells is phenomenal however fetal stem cells have to come from a developing embryo and some people believe that life begins as soon as sperm meets the egg and so they have a efendim fundamental problem with fetal stem cell research my opinion not as your instructor but just as a person is we have millions and millions of embryos sitting in cryogenic freezers because of in vitro fertilization when a couple goes in for IVF they usually create between five and 20 embryos and say they get pregnant right away well then there's all these would be children that are just hanging out on ice and I hate to be insensitive but they can't last forever they'll eventually get the equivalent of freezer burn once there's ice crystals in that tissue the tissue dies so my personal opinion is I think it's a much better use of those embryos to maybe help people with spinal cord problems or Alzheimer's or heart attacks or muscular dystrophy Parkinson's disease all these horrible diseases that we have in people that are currently alive and living their lives than just letting these these cells die but again it's just my opinion so feel stuffy during the fetus during during kind of development here blood is very different when you're you know a fetus when you're an embryo when you're shortly born when you're an infant when you're a child versus when you're an adult because if you think about fetuses or you think about babies or you think about toddlers these kids are growing like insane right kids grow so fast and as they grow they have to fill in all those spaces with blood whereas as an adult I don't know what your kids are into but you shouldn't be like bleeding every day like most of us aren't going out and like you know racing motorbikes or whatever that gets us into shenanigans most of us are laying on the couch so like although you make clot occasionally you're probably not spending a big chunk of your time clotting and so we just need to maintain our blood because blood cells die every hundred and twenty days so we do need to keep up with the ones that are dying but it's not like we're trying to fill like a whole body with blood so as a fetus there are no there's no bones yet there's no bone marrow yet so the blood cells can't come from the bone marrow they come from your yolk sac which yes you have a yolk sac very early on in development and the liver in the spleen but after birth it's all red bone marrow if you remember from a EP one there's two types of bone marrow there's red and yellow yellows fat marrow and Redis is to make the blood so in an infant and growing child and toddler almost all of your bones have red bone marrow because almost all of your 206 bones need to be making blood because you've got to keep up with this intense amount of growth where as an adult we don't make blood from all of our bones so most of our red bone marrow which is what makes the blood is in the epiphysis of the long bones the epiphysis are the ends of the bones if you remember from a mp1 so especially like your hip if you're a member of that femur has that huge head on it in that ball and socket joint and so you make a ton of blood in your femur you make a ton of blood in your hip bones your vertebrae your sternum and your ribs and some of your skull bones so you don't need to know all these specific examples what I would want you to know is babies are making blood everywhere all of their bone marrow whereas adults we just don't need to so it's limited to a few bones red blood cell formation goes through these five steps I really only need you to know details about number one and number five so it starts out in your bone marrow as a pluripotent stem cell so you don't need the term pluripotent in your life but it's like I was saying on the last slide fetal cells are what we call totipotent they can totally which is how I remember it become any cell in your body so that's like when it when a baby is born we look at it and say you can be anything when you grow up because they can right a pluripotent stem cell is like you guys you've chosen medicine maybe you haven't committed to nursing a rad tech or dental hygiene or med school but you're not an A&P to for funsies this is not a fun class right it's hard class so you guys have at least committed to medicine most you are going to go into the medical field in some way I doubt there's too many art majors in this class so pluripotent means these guys can be any type of blood cell but they've at least committed to the blood these guys are in your bone marrow and they can be any blood cell and they still have a nucleus so like I said we don't need details about two three and four but two is what we call excuse me a colony forming unit so this cell has receptors for a wreath ro poitain so remember hormones we can dump a whole bunch of hormones into your blood and remember they only affect the tissues that have the right receptors like keys only open locks that fit them and so this guy is gonna respond to a wreath ro poitain to become a red blood cell so once he responds to that hormone he becomes a wreath wrote on a wreath robe last if remember blast means to build so now that he's chosen to become an erythrocyte he's got to make hemoglobin like crazy because that's his job the nucleus is also gonna shrivel up and get squirted out of the cell because you don't need it if you're gonna become a red blood cell right reticulocytes is the stage it goes through where it has tons and tons of ribosomes ribosomes make protein which is a big component of hemoglobin and then we have the mature erythrocytes so these are just the stage as it goes through but again I just care about stage one in stage five that it starts out as a pluripotent stem cell that has a nucleus because remember if these guys choose to become leukocytes they would need the nucleus but once this guy commits to become an erythrocyte he gets rid of his this picture is just showing the genesis of the red blood cell so you can see the pluripotent stem cell with its nucleus the colony forming unit which is going to start to respond to the hormone erythropoietin they read throw blasts which is going to start building that hemoglobin the reticulocytes with all the ribosomes because we're getting ready to make all these proteins and then the erythrocyte the mature cell no nucleus the most important chemical in your blood is hemoglobin so hemoglobin is abbreviated HB which has always driven me crazy but if you look at the periodic table of the elements HG is mercury so it's like that abbreviation was already taken so we're stuck with HB which I hate so this is a molecule if you look at the chemistry a crazy molecule that's inside your red blood cells it contains protein so if you look at the picture the yellow and the blue there it's like two strings of amino acids and then the very center if you look at the bottom picture has an Fe which is iron so there's one little iron in there and then all of the other proteins so this molecules shape is what we call tertiary and you don't have to know this but it's the or I'm sorry hah quaternary this guy has the fourth level of protein structure so you have primary secondary tertiary and quaternary so quaternary is the highest hemoglobin has the highest so for us because this isn't chemistry I just want you to know that hemoglobin is hella complicated so if you remember from a mp1 or from a biology class kind of talking about protein structure how there's 20 amino acids and it's also protein is the most complicated molecules in our body and because they're complicated they're really really sensitive to being broken down so hemoglobin is trapped inside your red blood cells which is trapped inside your arteries and veins deep inside your body to protect it from UV light because if if UV light strikes hemoglobin it destroys it so it's just it's a very very sensitive protein whereas proteins that have primary structure would be like your hair your hair is one straight row of amino acids whereas this is like curlicues of proteins and all kinds of other things going on I mean it's very very complicated so just looking at this molecule if I took out one of those bonds it would no longer be hemoglobin so it's just incredibly sensitive to being broken down which is why it's so protected but otherwise it's a genius molecule in the sense of transportation so one hemoglobin molecule which is shown there in letter B can carry four molecules of oxygen which makes sense structurally if you look at it looks like it could carry four things one red blood cell has 250 million hemoglobin molecules which means one red blood cell can carry a billion oxygen then you have twenty five trillion red blood cells so 25 trillion times a billion is a lot like I don't know what that is but that is a lot but then you think well we have to transfer oxygen 24/7 to every cell in our body I mean it has to be that way but it's still very impressive hemoglobin is the molecule but when it's bound to things its name changes so oxyhemoglobin is when hemoglobin has oxygen on it carb Amina hemoglobin which is kind of fun to say is when hemoglobin is bonded with carbon dioxide and then carboxyhemoglobin is when it's bonded with carbon monoxide which is the stuff that comes out of your tailpipe and kills you don't do that hemoglobin is such an important molecule but it's also a quote-unquote expensive molecule for our body to make because protein remember is hard to come by it's expensive to hit the meat department at Walmart whereas if I went down the pasta aisle I can buy a spaghetti for days right so anytime you have something that's protein based your body has a lot of effort invested in that so if I've got all these hemoglobins wrapped up inside red blood cells that are dying every four months I want to make sure I break that hemoglobin down and reuse it because remember I'm just gonna turn around in my bone marrow and make more red blood cells so I might as well recycle this hemoglobin so the organ that does the majority of this is your spleen so the spleen we call the red blood cell graveyard because that's his job he's breaking the red blood cells down he's also then gonna break down that hemoglobin so we can just reuse it what happens to the hemoglobin in the spleen well when you split it you're gonna get a heme and a globin which makes sense right so the heme is gonna be further broken down into iron and bilirubin so Billy Ruben remember we mentioned we were talking about hemolytic disease of the newborn so Billy Ruben is something that you your body can process and recycle if your liver is healthy because you take that iron and your Billy Ruben you take it to the liver it has kind of a yellowish pigment to it which is why people with jaundice get a buildup of bilirubin and like you can see the yellow in their eyes globin is a protein so if I break glob and down I'll just break it down into amino acids I can use those amino acids to build more globulin or I can just use those amino acids to build hair and skin and nails and everything else I mean your whole body's protein based right so recycling these amino acids you have endless uses for them once these things have gone to the liver we're going to convert them to useful forms the iron the iron we're gonna store it you do not need to know Hema sarahdan and ferritin but these are just the ways that we store iron it's kind of like you can store money in your sock drawer in a mason jar in your garden or in an IRA it's just different ways of storing money well there's different ways of storing iron but we just need to know we're gonna store the iron iron is kind of like proteins it's a very precious thing that you had to get from your diet so you definitely don't want to waste it when you're gonna turn a ride around and build more hemoglobin the bilirubin your liver converts to bile which is part of the name which helps you break down fat this diagram illustrates the life and death of a red blood cell so starting in the small intestine you have to absorb nutrients so these are the main nutrients that you need to make red blood cells we've got to have the amino acids for the proteins we got to have the iron for the hemoglobin folic acid is just a bite you know basically a vitamin that you have to have in order to make red blood cells as well as vitamin b12 so these are just components that you're gonna have to get in your diet like if I'm building something I have to get this stuff from Home Depot arethe row poises again is that nerdy word that just means the making of red blood cells begins then in the red bone marrow the erythrocytes circulate for about 120 days and then this next step see how the liver and the spleen are both in that picture the arrow is going directly to the spleen this is very important the spleen that's his main gig but you can be without your spleen right like if something happens and they have to take out your spleen you don't die because the liver could then step up so the liver is the backup for breaking down a wreath recites that's not the livers main job but he can do it if necessary so that's why he's kind of off to the side this is the spleens main gig so the hemoglobin is gonna get broken down so remember globin we're done we're breaking it down into amino acids like that little flowchart says and then it we're done whereas the heme we break down into bilirubin and iron technically it breaks down into billy verdun first but that's kind of a very quick molecule before it becomes bilirubin so most people just talk about bilirubin but Billy Verdun is kind of the precursor to bilirubin and Verde in Latin means green so this is why the bile is greenish the gallbladder is green which we'll eventually see on the cadaver and it's still green on them so that becomes bile again exits you know in your fecal matter eventually whereas the iron we want to keep because we're gonna store it we're gonna reuse it we're gonna store it we're gonna reuse it because we're going to make hemoglobin until we die but sometimes you do lose iron injury or if you donate blood you're not obviously holding on to that iron and ladyparts when we go the joy of menstruation the monthly period some women lose a lot of blood and especially if you're really skinny that blood loss could lead to an iron deficiency so some women take iron supplements because they lose so much blood during that time if the liver is not functioning properly basically if the liver ain't happy ain't nobody happy the liver does a lot of stuff okay but in this case if your livers not functioning we're talking about the blood you're not gonna convert that Billy Reuben to bile because that's the livers job so you get jaundice which the skin develops a yellow tint bilirubin starts to build up in the bloodstream lots of things can cause this hepatitis so any kind of liver diseases but it can also be a blockage of your bile ducts but or it can be like in babies babies get jaundice because the liver just kind of hasn't kicked into gear yet so lots of things could cause jaundice what are the jobs of a wreath Row sites we get obsessed with them carrying oxygen which is true that is their main gig and that's obviously the one we think that we need but they pick up the carbon dioxide as well so it's just important for the pizza man to bring me a pizza as it is for my trash man to take the pizza box away so they're carrying both oxygen and carbon dioxide this helps to balance your pH as we'll see basically carbon dioxide bonds with the water in your blood and forms a very weak acid so the point is we've got to get that carbon dioxide out of there otherwise we would acidify our blood they only live about 120 days although the previous slide talked about the spleen a little bit this is kind of showing you a picture of it we'll see it on the cadaver the cadavers have their spleens spleen is kind of a fun word so we mentioned it as where red blood cells get broken down but your white blood cells and platelets also get broken down here so he really is your blood graveyard as a fetus he produces red blood cells because remember a fetus doesn't have bone marrow yet and as an adult you store some blood here so basically if you go through a situation where you need some blood say you donate a blood or you got injured the spleen can spasm and squirt out its extra blood so it's almost like you give yourself a transfusion it also removes a lot of debris and foreign material so like if you have a bacterial infection or a virus phagocytosis occurs here my favorite science word remember is just like the little gobbling up so it does clean but because other organs do these jobs too you can live without your spleen it's not ideal but you can survive