Flow through the Heart, Saúde e Medicina Khan&DuoLingo*Igor_MSA

So what you're looking at is one of the most amazing organs in your body. This is the human heart. And it's shown with all the vessels on it and you can see the vessels coming into and out of it but the heart at its core is a pump and this pump is why we call it one of the hardest working organs in your body, because the heart starts pumping blood from the point where you're a little fetus and you're eight weeks old all the way until the point when you die. So this organ I think it will be really cool to look at it in detail but it's hard to do that looking just at the outside, so what did is I actually drew what it might look like at the inside. So let me just show you that now and it will follow the path of blood through the heart using this diagram. Let me start with the little picture in the corner so let's say we have a person here this is teir face, this is their neck and I'm gonna draw their arms and they have in the middle of their chest their heart. So the whole goal was to make sure that blood from all parts of the body, including their legs will make its way back to the heart first of all and then get pumped back out to the body. So blood is gonna come out from this arm let's say dumped into the air and the same on this side, and it's gonna come from their head and all three sources two arms and a head are gonna come together into one big vein. And that's gonna be dumping into the top of the heart. And then separately you have veins from the legs. Meaning veins from the belly. Coming into another opening into the heart. So that's how the blood gets back to the heart. And anytime I mention the word vein, I just want to make sure you think of blood going towards the heart. Now If blood is going towards the heart, after the blood is pumped by the heart, it´s gonna have to go out to the heart. Right it´s gonna have to go away from the heart. So that´s the aorta. The aorta actually has the little arch like that. We call that the aortic arch. And it sends off one vessel to the arm, one vessel up this way, the vessel over this way and then this arch gonna go down and splits like that. So this is kind of simplified version of it. You can see how there are definetely some parallels between how the veins and arteries are set up. And arteries or anytime I mention the word artery, I want you to think about the blood going away from the heart. And easy way to remember that is that both start with the letter "A". So going to the big diagram we can see that blood´s coming this way and blood´s coming this way is ending up with the same spot. It´s going to end up at the, maybe I should draw it here, it´s ending up with the right atrium. That´s just the name of the chamber where the blood ends up in. And it came up in the right atrium from a giant vessel up top called the superior vena cava. And this is a vein of course because it´s bringing blood towards the heart. And down here the inferior vena cava. So these are the two direction the blood is going to be flowing. And once the blood is in right atrium, it´s going to head down into the right ventricle. So this is the right ventricle, down here. This is the second chamber of the heart. And it gets there by passing through the valve. And this valve and all valves in the heart are basically there to keep blood moving in the right direction. So it doesn't go to backwards direction. So this valve is called the Tricuspid valve. And it´s called that because it´s basically got three little flaps. That´s why they call it tri-. And I know you can only see two in my drawing and that´s just because my drawing is not perfect.

And it´s hard to show kind of flap coming out of juby you can imagine it.

So blood goes into the rigt verticle and where it goes next.

Well after that it´s gonna go this way: it´s going to go to this vessel and it´s gonna split.

But before it goes it has to passed another valve.

So this is a valve right here.

Call it Pulmonary valve.

And it gives you the clue where the things we are going to go next.

Because the word pulmonary means lungs.

And so if this is my lung on this side. This is my left lung.

And this is my right lung on this side.

Then these vessels and all that they trying to get will be called, these vessels, this will be my, make sure I get my right and left straight, this is my left pulmonary artery.

And I hesitated there just to make sure I got that because it´s taking blood away from the heart.

And this is my right pulmonary artery.

So this is my right and left pulmonary artery.

As the blood goes down into my lungs, right. these the lungs that kind of nessel into my thorax, where my heart is sitting, goes into my lungs

and remember this blood is blue.

Why is it blue? Well,it´s blue because it doesn´t have very much oxygen.

So one thing that I need to pick up is oxygen.

So that´s one thing what the lungs gonna help me pick up and I´m gonna write O2 for oxygen.

An it´s also blue and that reminds us that it´s full of carbondioxides, full of wastes.

Because it´s coming from the body.

Well the body made a lot of carbondioxides that it's trying to get rid of.

So in the lungs you get rid of the carbondioxides and you pick up oxygen.

So that´s why I switch it in this point blue colored vessel to red colored vessel.

So now blood comes back this way and this way and dumps into this chamber.

So what is that - that is our left atrium.

So just like our right atrium we have one on the left.

And it goes down into, you can probably guess how this one is called, is our left ventricle.

So just like before where we went from the right atrium to the right vertricle, now we´re going from the left atrium to the left ventricle.

And it passed through the valve here. So this valve is called the Mitral valve.

And it´s job is of course to make sure the blood does not go from the left ventricle back to the left atrium by accident.

Wants to make sure there is forward flows.

And then the final valve, I need to find a nice spot to write it maybe to right here, this final valve that passes through is called the Aortic valve.

And the Arotic valve is going to be what divides the left ventricle from this giant vessel that we talked about earlier.

And this is of course the aorta. This is my aorta.

So now blood is gonna go through the aorta to the rest of the body.

So you can see how blood now flows from the body into the four chambers.

The first into the right atrium. This is chamber number one.

And then it goes into the right ventricle. This is chamber number two.

It goes to the lungs and then back up to the left atrium. So this is chamber number three.

And then the left ventricle.

And this happens every moment of every day, everytime you heard your heart beating, this process is going on.