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Current time:0:00Total duration:8:14

Video transcript

so what if we had a truck or a bunch of trucks and inside the trucks we have boxes and and the boxes are carrying money so we're going to make this interesting and we're going to talk about trucks that are delivering money and these trucks are being loaded right they're being loaded at their warehouse at their warehouse and from the warehouse they're shipping out the money to different places so they're shipping out money to the government right because the government needs money and they're shipping it out to stores right and I don't know to two people right people people people and of course some of the money also has to go back to the warehouse because all of these entities from the government to people to the warehouse need the money to survive to function so it's not too hard to understand this whole setup right but it actually bears a striking resemblance to our own circulatory systems let's take a look at what our circulatory system looks like well in our blood instead of having trucks we have red blood cells so that's these things over here and these red blood cells carry lots and lots of oxygen and so the oxygen is kind of like money in this situation but the oxygen doesn't just float around in the red blood cell willy-nilly instead it's really neatly packaged and really neatly bound to hemoglobin so hemoglobin is this molecule in the center and you can see that each molecule of hemoglobin is bound to four molecules of oxygen okay and just like the trucks were loaded up at the warehouse these red blood cells are loaded up with oxygen at a warehouse of sort so first the red blood cells are loaded up with oxygen at the lungs and then after being loaded up they're sent to the heart which pumps the red blood cells out to the rest of the body okay so now these red blood cells are filled up with oxygen which they then deliver to all of the different organs and tissues throughout the body so for example they deliver oxygen to the brain right because the brain needs lots and lots of oxygen to the kidneys right to the kidneys to the skin to the skin and of course some of the oxygen or or actually a lot of the oxygen has to come back to the heart right into the lungs so all the organs all the tissues all of the cells in our body absolutely need oxygen to survive in to function and that's what makes it so important so so that's what the circulatory system is all about but let's talk about the topic of this video we were supposed to talk about anemia so what is anemia well anemia is a shortage or a reduction in the number of red blood cells so there aren't as many red blood cells in the body as we need and as you can imagine this leads to a decrease in the oxygen delivery the oxygen delivery to tissues to tissues okay and really it's the decrease in the oxygen delivery to the tissues that accounts for all of the symptoms of anemia so for example if the brain if there's not enough oxygen being delivered to the brain you get symptoms such as fatigue right so you start to feel really tired right um dizziness dizziness dizziness a patient can start to feel person can start to feel really dizzy if their brain isn't receiving enough oxygen and it can become really difficult right difficult to think and to concentrate to concentrate trait okay what about if the heart doesn't receive enough oxygen well well that leads to chest pain chest pain and as you can imagine chest pain really starts to occur in situations where the heart is working harder than it usually does so situations such as exercise because when we exercise our heart beats not only faster but it beats stronger than it does at rest and that means that the heart needs more oxygen than it does at rest so if the person who's exercising also suffers from anemia right in which there is a reduction in the number of red blood cells and a reduction in the oxygen being delivered to the heart that can precipitate an episode of chest pain and that also happens in situations of emotional stress because we know that when we're freaking out our heart starts to beat really fast and of course that means it needs more oxygen and again chest pain becomes a problem and another thing that happens is is when there aren't enough red blood cells the skin starts to appear pale that's called pallor okay when the skin kind of loses its color that's called pallor so I made a big fuss I made a big deal to say that oxygen is really important for the functioning and the survival of all the tissues in the body so you better believe that the body recognizes immediately when there isn't enough oxygen being delivered to the tissues and it does its absolute best to fix that problem okay it does that in a bunch of different ways I think that's a lot easier to understand if we go back to this truck analogy so what if you were the manager of this whole system and all of a sudden your customers the government stores and the people weren't getting enough money because there was a shortage in the number of trucks what would you do well you might start off by saying hey we need to increase the amount of money that we pack into each of these trucks so that each truck is carrying more money and that would be a great idea but after a short while you'd recognize that hey the trucks are packed full of money they can't hold anymore so you got to come up with another solution and that other solution might be to make these trucks dry faster so you would increase the speed at which these trucks are traveling so that they can reach the customers more quickly turn right back around get loaded up with money at the warehouse and then go right back out there to deliver that money once again so you'd be increasing so increasing the speed speed of the trucks to increase this to increase the amount of money being delivered per unit time would also be a good idea and finally when you have a second you'd get right on the phone with a guy who supplies you with your trucks and you tell him to increase his production his production of trucks so that his production of trucks and send them your way so that you can you can address the problem at the source right well that's exactly how our body I mean exactly how our body deals with the situation of anemia so first it addresses the issue by increasing the amount of oxygen that's brought into the body how can we possibly do that well you can do that by breathing faster or increasing our respiratory rate or the rate at which we breathe okay second thing that the body does is it says hey let's pump out these red blood cells from the heart faster so that they can deliver the oxygen to the tissues come right back get loaded up in the lungs and then get pumped out again okay so the heart says I'm going to send these out with a greater velocity I'm going to pump faster I'm going to increase the heart rate okay and then finally the body tries to address the issue at it's very core so it tries to increase red blood cell production production to sort of counteract the anemia and we'll talk a little bit more later about how that's possible how you can go about increasing red blood cell production and whether that works or not whether the body responds by making more red blood cells or not