Circulatory System | Pulmonary Circulation

all right Ninja nerds in this video we're going to talk about the pulmonary circulation the pulmonary circulation is extremely important within the body because its function is to be able to take blood from the right side of the heart to the lungs for the lungs to get oxy the lungs to oxygenate the blood so we need to take the oxygen from the lungs and put it into the blood that the next thing that's also really important for the pulmonary circulation is to take the CO2 out of the blood and put it into the lungs so

that the lungs can actually exhale it and then take that new oxygenated blood and deliver it to the left side of the heart so recap that purpose of the pulmonary circulation is to pump blood from the right side of the heart to the lungs where in the lungs the the blood is going to pick up the oxygen drop off the CO2 and be taken to the left side of the heart let's go ahead and discuss this in detail so what we're going to do is we're going to actually follow each one of these vessels and

Chambers and valves that we're going to move through but we're just going to number it for right now and then we're going to write down what each number represents so starting the circuit off here at the first position here is going to be within What's called the right ventricle okay so we always want to start a circuit at the pump because he's the one who's actually driving the circuit so the right ventricle is going to be the actual starting point for the pulmonary circulation so this next thing is from one we got to pump it

from the right ventricle up into the pulmonary trunk but in order to do that I got to pump it through these valves these pulmonary semi lunar valves so the second thing is I'm going to have to move through the pulmonary semi lunar valves okay so first is right ventricle second is the pulmonary semi lunar valve then when I pump it up through the pulmonary semi lunar valves I pumped into this big old trunk so they call this the pulmonary trunk so this third position right there is the pulmonary trunk then the pulmonary trunk gets to

this bifurcation point where it can split going to the actual vessels on this side since you guys are looking at the camera and we're looking at like in this orientation we're going to say this is the right side and this over here is the left side so when it splits it goes into a right pulmonary artery and a left pulmonary artery okay so for these guys we're just going to number it only on this side because we're focusing more on this side but understand that it would be the same thing over here so again right

ventricle through the pulmonary semilunar valve into the pulmonary trunk and from that it splits into right and left pulmonary arteries now you guys might be looking at this and saying whoa why aren't arteries supposed to be red no not in this situation because the pulmonary arteries are actually carrying deoxygenated blood so because they're carrying deoxygenated blood that's why we're representing it here in blue another example of this is actually going to be the fetal circulation where the umbilical veins were actually oxygenated and the umbilical artery was deoxygenated just remember that arteries are taking blood away

from the heart and veins are bringing blood back to the heart okay so that's really crucial to understand so now we got the pulmonary arteries right and left the pulmonary arteries will come into the lungs where like in a root kind of structure through the the highis of the lung which is like a little slit-like potential space when it moves in it gives off another Branch so it gives off a couple branches here and these are these guys here you can see it one two three these are called your pulmonary arterials these are just small

arteries very very high resistance vessels anytime you hear the word arterial think about a resistance vessel so it controls the actual constriction and dilation responses then from here the arterial branches into these nice little capillary exchange vessels these are going to be very very important why because at the capillary exchange site that is where we said we're picking up oxygen and then what are we dropping off we're dropping off CO2 okay so that's crucial there so just remember that that in these capillary vessels here as we go from the pulmonary arterials to the pulmonary capillaries

what's happening in the pulmonary capillaries we're picking up lungs I'm sorry we're picking up oxygen and dropping off the CO2 okay so this is the oxygenation process or the gas exchange process and it's the gas exchange is actually occurring between a small little structural unit within the lungs called the alvioli okay sweet deal then what happens is from these pulmonary capillaries they drain into these individual little things that you see here you see this red one there red one there red one there these guys number seven is going to be your pulmonary venules okay so

these are called your pulmonary venules they're small veins so we have pulmonary arterials which are small arteries then we go into these guys here which are called your capillaries or the exchange vessels and then we go into the small veins which are called pulmonary venules then the pulmonary venel 1 2 3 come together and make up a nice big old vein this is called the pulmonary veins and when you take the pulmonary vein the pulmonary vein you're going to notice oh it's red that means it's oxygenated that's because we picked up oxygen and dropped off

CO2 the pulmonary veins are going to do what then they're going to bring the blood out of the lungs they're going to take the actual blood out of the lungs and drop it off back to the heart but now on what side of the heart now we're on the left side of the heart the left side of the heart is the oxygenated side the right side of the heart is the deoxygenated side so now the ninth Point here is we're going to be in the right atrium okay I'm sorry left atrium okay so the next

point we're going to be at is the left atrium then from the left atrium we got to push the blood down through these valves you see these little valves right there these are important little guys especially on the left side it has two names you can either call it the the actual bicuspid valve or you can call it the mital valve okay so from there we're going to go from to the left atrium the left atrium is going to pump it down through the mitro valve and into this nice little chamber here which is called

the left ventricle all right so like always repetition is the key to being able to remember these things because unfortunately it's just it's just a lot of raw memorization so let's go ahead and get started in here so to kind of recap it all we're going to start off with number one what is number one here it's going to be the right ventricle so the right ventricle was the pump it was starting the circuit the second point was going to be going through the pulmonary semi lunar valve that was the next structure that we had

to go through then after that we had to pump it into the pulmonary trunk so then that was the next one so from the from that into the pulmonary trunk then what then from the pulmonary trunk we distributed into the right and left pulmonary arteries so I'm going to put here pulmonary arteries then from that we had to go to the next point the pulmonary arteries broke down into different types of smaller arteries called pulmonary arterials so then we went to pulmonary arterials then from the pulmonary arterials we go into these nice little capillary exchange

vessels to be able to pick up the oxygen and drop off the CO2 so the sixth Point here is going to be the pulmonary capillaries then after that after the exchange has occurred we're going to take it out of these pulmonary capillaries and into these small little veins what are those called postcapillary venal they're actually going to be called in this case since they're postc capillary venal we call them pulmonary venal so we're going to call this pulmonary venules then from the pulmonary venules these venules are going to come all together and form one big

old fat vein that's called the pulmonary vein so then you're going to go into What's called the pulmonary vein then from the pulmonary vein the pulmonary vein is going to bring the blood back to the left atrium so it's going to bring it to the left side of the heart and this is going to be the left atrium from the left atrium we're going to pump the blood down through what valve it's called the mital valve or the bicuspid valve so we're going to call this one the mital or bicuspid valve then from that we're

going to go into the last structure here and the last structure that we're going to enter into is going to be the left ventricle so the last one that we'll go into is What's called the left ventricle left ventricle is going to end the pulmonary circuit but begin another circuit it can actually begin the systemic or even the coronary circuit because he's in responsible for the systemic circulation the right ventricle is primarily important for the pulmonary circulation Allon Engineers I hope all of this made sense I really do hope that you guys enjoyed it if

it did make sense please hit the like button comment down in the comment section and please subscribe as always engine nerds until next time