[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:01.00,0:00:04.00,Default,,0000,0000,0000,,Let's say that this is you. You're enjoying a nice sunny day
Dialogue: 0,0:00:04.00,0:00:09.00,Default,,0000,0000,0000,,and you decided to take a nice long deep breath of air.
Dialogue: 0,0:00:09.00,0:00:15.00,Default,,0000,0000,0000,,And of course when I say air the part that you \Nprobably care the most about is just the oxygen,
Dialogue: 0,0:00:15.00,0:00:21.00,Default,,0000,0000,0000,,part of that air, that's the part that \Nwe as humans need to survive.
Dialogue: 0,0:00:21.00,0:00:24.00,Default,,0000,0000,0000,,So you take a deep breath. \NLet's say you take it through your mouth,
Dialogue: 0,0:00:24.00,0:00:26.00,Default,,0000,0000,0000,,you take a deep breath through your mouth.
Dialogue: 0,0:00:26.00,0:00:30.00,Default,,0000,0000,0000,,And then lets say you take one more deep breath, \Na second deep breath,
Dialogue: 0,0:00:30.00,0:00:31.00,Default,,0000,0000,0000,,and then you take that one through your nose.
Dialogue: 0,0:00:31.00,0:00:36.00,Default,,0000,0000,0000,,And you might think, "Well, these are two totally \Ndifferent ways of getting in air."
Dialogue: 0,0:00:36.00,0:00:40.00,Default,,0000,0000,0000,,That's certainly how it looks when \Nyou look at the mouth and nose.
Dialogue: 0,0:00:40.00,0:00:42.00,Default,,0000,0000,0000,,They don't look like they have much in common.
Dialogue: 0,0:00:42.00,0:00:45.00,Default,,0000,0000,0000,,But the truth is that actually if you follow the air,
Dialogue: 0,0:00:45.00,0:00:50.00,Default,,0000,0000,0000,,it almost follows an identical path.
Dialogue: 0,0:00:50.00,0:00:56.00,Default,,0000,0000,0000,,The air is gonna go into the back of the throat \Nreally regardless of how you took it in.
Dialogue: 0,0:00:56.00,0:00:59.00,Default,,0000,0000,0000,,So here we have air coming in from the nose,
Dialogue: 0,0:00:59.00,0:01:03.00,Default,,0000,0000,0000,,in here yet air coming in from the mouth \Nand they meet up in the back of throat.
Dialogue: 0,0:01:03.00,0:01:10.00,Default,,0000,0000,0000,,And then they go down down down,\Nthey go towards this thing that we call the Adam's apple.
Dialogue: 0,0:01:10.00,0:01:14.00,Default,,0000,0000,0000,,I'm gonna bring it up a little bit, you can see it more easily.
Dialogue: 0,0:01:14.00,0:01:19.00,Default,,0000,0000,0000,,But basically you bring up this, you see \Nthis Adam's apple right there.
Dialogue: 0,0:01:19.00,0:01:22.00,Default,,0000,0000,0000,,And actually you can go ahead and \Ntake a feel of you own Adam's apple.
Dialogue: 0,0:01:22.00,0:01:27.00,Default,,0000,0000,0000,,It's a pretty cool structure in the middle of your throat
Dialogue: 0,0:01:27.00,0:01:30.00,Default,,0000,0000,0000,,and everybody has it, that's the first thing I want to tell you,
Dialogue: 0,0:01:30.00,0:01:34.00,Default,,0000,0000,0000,,that everybody has it, not just men, women have it too.
Dialogue: 0,0:01:34.00,0:01:41.00,Default,,0000,0000,0000,,And the reason it's called an Adam's apple \Nis because "Adam" is generally a boy's name.
Dialogue: 0,0:01:41.00,0:01:49.00,Default,,0000,0000,0000,,And so it's to remind us that usually men or boys \Nhave larger Adam's apples than girls.
Dialogue: 0,0:01:49.00,0:01:54.00,Default,,0000,0000,0000,,And if you're trying to find it, \NI also want to point that it's a notch here.
Dialogue: 0,0:01:54.00,0:01:57.00,Default,,0000,0000,0000,,And you if you can feel the notch with your fingers,
Dialogue: 0,0:01:57.00,0:02:00.00,Default,,0000,0000,0000,,in that case you have a nice clue as to where it is located.
Dialogue: 0,0:02:00.00,0:02:06.00,Default,,0000,0000,0000,,This is Adam's apple and what it does is, \Nit helps you control your voice.
Dialogue: 0,0:02:06.00,0:02:08.00,Default,,0000,0000,0000,,And actually there's another name for Adam's apple.
Dialogue: 0,0:02:08.00,0:02:13.00,Default,,0000,0000,0000,,Another name for it, sometimes \Npeople call it the voice box. The voice box.
Dialogue: 0,0:02:13.00,0:02:21.00,Default,,0000,0000,0000,,And of course air is passing through the voice box \Nin this kind of the entry way into the trachea.
Dialogue: 0,0:02:21.00,0:02:28.00,Default,,0000,0000,0000,,And so it actually allows me to make my voice \Nvery high or make my voice very low,
Dialogue: 0,0:02:28.00,0:02:34.00,Default,,0000,0000,0000,,depending on how you change \Nthe muscles around in that Adam's apple.
Dialogue: 0,0:02:34.00,0:02:39.00,Default,,0000,0000,0000,,So that's actually kind of a first cool thing I want to point out to you, that you can actually control your voice.
Dialogue: 0,0:02:39.00,0:02:44.00,Default,,0000,0000,0000,,I'm sure you knew this already but what you're using \Nis the Adam's apple, your voice box.
Dialogue: 0,0:02:44.00,0:02:49.00,Default,,0000,0000,0000,,Now air keeps going, air is just gonna \Nkeeps making its journey down and
Dialogue: 0,0:02:49.00,0:02:54.00,Default,,0000,0000,0000,,specifically of course the part of air I said, \Nyou know, we care about is the oxygen.
Dialogue: 0,0:02:54.00,0:02:58.00,Default,,0000,0000,0000,,It's gonna keep making its journey \Ndown into the lung areas,
Dialogue: 0,0:02:58.00,0:03:05.00,Default,,0000,0000,0000,,now the lung areas, it's gone down the trachea and it goes into the two lungs, the right and left lungs.
Dialogue: 0,0:03:05.00,0:03:11.00,Default,,0000,0000,0000,,This is the left lung, I'm gonna put L for left \Nand this is the right lung, I'll put R for right.
Dialogue: 0,0:03:11.00,0:03:14.00,Default,,0000,0000,0000,,And immediately you'll think, \N"Wait a second, aren't they switched?"
Dialogue: 0,0:03:14.00,0:03:19.00,Default,,0000,0000,0000,,Now I want you to remember that this is from the perspective of the person who owns the lungs.
Dialogue: 0,0:03:19.00,0:03:23.00,Default,,0000,0000,0000,,So that's why I put it in left where I put it, \Nin right where I put it.
Dialogue: 0,0:03:23.00,0:03:26.00,Default,,0000,0000,0000,,Now we should probably go ahead and \Nstart labelling some of these.
Dialogue: 0,0:03:26.00,0:03:30.00,Default,,0000,0000,0000,,You can see that the lungs actually \Ndon't look identical, right?
Dialogue: 0,0:03:30.00,0:03:34.00,Default,,0000,0000,0000,,They look slightly different, for example, \Nthis one has three lobes.
Dialogue: 0,0:03:34.00,0:03:40.00,Default,,0000,0000,0000,,The right side has three lobes called \Nthe upper lobe, middle lobe and lower lobe.
Dialogue: 0,0:03:40.00,0:03:45.00,Default,,0000,0000,0000,,And the left one only has two lobes, \Nthat's the first kind of a big difference.
Dialogue: 0,0:03:45.00,0:03:53.00,Default,,0000,0000,0000,,And the other difference is that you actually have \Nthis thing in the middle that we call a cardiac notch.
Dialogue: 0,0:03:53.00,0:03:57.00,Default,,0000,0000,0000,,This thing right here, this is called the cardiac notch.
Dialogue: 0,0:03:57.00,0:04:03.00,Default,,0000,0000,0000,,And the reason we call it that is that \Nit's a little spot that gets formed
Dialogue: 0,0:04:03.00,0:04:07.00,Default,,0000,0000,0000,,because the heart is literally kind of peeking out here.
Dialogue: 0,0:04:07.00,0:04:11.00,Default,,0000,0000,0000,,And as a result it's kind of makes a notch \Nin the lung where it develops.
Dialogue: 0,0:04:11.00,0:04:15.00,Default,,0000,0000,0000,,So the heart takes a little space here, this is the heart.
Dialogue: 0,0:04:15.00,0:04:22.00,Default,,0000,0000,0000,,And as a result, it takes or makes that notch. \NSo this is our heart space there.
Dialogue: 0,0:04:22.00,0:04:27.00,Default,,0000,0000,0000,,So on the other side you've got of course \Nyour two lobes, your upper and lower lobes.
Dialogue: 0,0:04:27.00,0:04:31.00,Default,,0000,0000,0000,,And these are exclusive, you see a lung \Nthat's kind of sitting by itself.
Dialogue: 0,0:04:31.00,0:04:36.00,Default,,0000,0000,0000,,And you want to figure out whether \Nit's the left lung or the right lung,
Dialogue: 0,0:04:36.00,0:04:40.00,Default,,0000,0000,0000,,you can look for the lobes, the number of lobes, \Nor you can look for that cardiac notch.
Dialogue: 0,0:04:40.00,0:04:45.00,Default,,0000,0000,0000,,Now around here, around these lungs, you've got ribs.
Dialogue: 0,0:04:45.00,0:04:52.00,Default,,0000,0000,0000,,You've got ribs here and between the ribs \Nyou've got rib muscles and of course on both sides.
Dialogue: 0,0:04:52.00,0:04:59.00,Default,,0000,0000,0000,,And below the lungs and below the heart, \Nyou've got a muscle, a big muscle.
Dialogue: 0,0:04:59.00,0:05:05.00,Default,,0000,0000,0000,,Actually it's gonna come through here, \NI'm just gonna kind of go through the word heart,
Dialogue: 0,0:05:05.00,0:05:08.00,Default,,0000,0000,0000,,and it basically becomes the floor.
Dialogue: 0,0:05:08.00,0:05:14.00,Default,,0000,0000,0000,,So the heart and the two lungs sit on this floor \Nthat made up of this muscle
Dialogue: 0,0:05:14.00,0:05:21.00,Default,,0000,0000,0000,,and this muscle is the diaphragm muscle. \NSo this diaphragm muscle makes up the floor;
Dialogue: 0,0:05:21.00,0:05:26.00,Default,,0000,0000,0000,,the ribs make up the walls. So what do we have?
Dialogue: 0,0:05:26.00,0:05:32.00,Default,,0000,0000,0000,,We have basically a room, we have a giant room \Nwith walls and the floor.
Dialogue: 0,0:05:32.00,0:05:36.00,Default,,0000,0000,0000,,And this entire room we actually call the thorax.
Dialogue: 0,0:05:36.00,0:05:40.00,Default,,0000,0000,0000,,So within this room then you have \Nyour two lungs and your heart.
Dialogue: 0,0:05:40.00,0:05:46.00,Default,,0000,0000,0000,,So, so far so good, but I haven't done a very nice job \Nof actually showing you where the air goes.
Dialogue: 0,0:05:46.00,0:05:51.00,Default,,0000,0000,0000,,I just kind of pointed that it goes to the two lungs, \Nwe don't have to get to see where it goes after that.
Dialogue: 0,0:05:51.00,0:05:53.00,Default,,0000,0000,0000,,So let me actually, I'm gonna erase a lot of these.
Dialogue: 0,0:05:53.00,0:05:59.00,Default,,0000,0000,0000,,I’m gonna reveal to you what it would look like. \NIf you could slip on some X-ray glasses
Dialogue: 0,0:05:59.00,0:06:03.00,Default,,0000,0000,0000,,and look into your two lungs, \Nthis is kind of what it would look like.
Dialogue: 0,0:06:03.00,0:06:11.00,Default,,0000,0000,0000,,You've got all these interesting architecture and \Nthe easiest way to kind of think about this,
Dialogue: 0,0:06:11.00,0:06:14.00,Default,,0000,0000,0000,,probably the simplest way to think about this, \Nis to imagine a tree,
Dialogue: 0,0:06:14.00,0:06:19.00,Default,,0000,0000,0000,,to imagine a tree, and that tree \Nhas been flipped upside down,
Dialogue: 0,0:06:19.00,0:06:24.00,Default,,0000,0000,0000,,so you've got all these branches of that tree \Nand they are branching and branching.
Dialogue: 0,0:06:24.00,0:06:31.00,Default,,0000,0000,0000,,And if you flip this tree upside down, you start seeing that it looks a lot like what we have in our lungs.
Dialogue: 0,0:06:31.00,0:06:37.00,Default,,0000,0000,0000,,Our lungs basically look like a flipped up or \Na flipped upside down tree and we even call that,
Dialogue: 0,0:06:37.00,0:06:42.00,Default,,0000,0000,0000,,we even call this entire structure, \Nwe call it a bronchial tree.
Dialogue: 0,0:06:42.00,0:06:47.00,Default,,0000,0000,0000,,So when you look at the lungs and \Nthey look kind of messier and complicated.
Dialogue: 0,0:06:47.00,0:06:52.00,Default,,0000,0000,0000,,Just think of them as an upside down bronchial tree \Nand all of a sudden
Dialogue: 0,0:06:52.00,0:06:57.00,Default,,0000,0000,0000,,it'll look much simpler with basically \Nin the middle you've got this nice trunk,
Dialogue: 0,0:06:57.00,0:07:01.00,Default,,0000,0000,0000,,this is our trunk, and then it's kind of \Nbranching from there.
Dialogue: 0,0:07:01.00,0:07:06.00,Default,,0000,0000,0000,,So air goes down this main trunk, this trachea, \Nand they kind of start splitting up.
Dialogue: 0,0:07:06.00,0:07:12.00,Default,,0000,0000,0000,,And each of this kind of colored regions, the green region and the purple region serve a different lobe.
Dialogue: 0,0:07:12.00,0:07:18.00,Default,,0000,0000,0000,,So this green region serves the lower lobe down here, \Nthe purple serves the upper lobe.
Dialogue: 0,0:07:18.00,0:07:23.00,Default,,0000,0000,0000,,And on this side, you've got an upper, \Na middle and a lower lobe.
Dialogue: 0,0:07:23.00,0:07:25.00,Default,,0000,0000,0000,,Now I know it looks a little bit strange because
Dialogue: 0,0:07:25.00,0:07:30.00,Default,,0000,0000,0000,,you’ve got some green branches in what should be \Nthe middle lobe like right here;
Dialogue: 0,0:07:30.00,0:07:34.00,Default,,0000,0000,0000,,you've got some orange branches in what \Nlooks like the upper lobe like right there.
Dialogue: 0,0:07:34.00,0:07:39.00,Default,,0000,0000,0000,,But what you have to remember, this is kind of tricky, \Njust try to play it in you head,
Dialogue: 0,0:07:39.00,0:07:45.00,Default,,0000,0000,0000,,what you have to remember is that, what you have \Nis basically a three dimensional lung.
Dialogue: 0,0:07:45.00,0:07:48.00,Default,,0000,0000,0000,,So you have to imagine that we are literally \Nlooking at the front side,
Dialogue: 0,0:07:48.00,0:07:52.00,Default,,0000,0000,0000,,but of course that middle lobe does go back.
Dialogue: 0,0:07:52.00,0:07:57.00,Default,,0000,0000,0000,,And if you went back then you'd make perfect sense\Nwhy the orange branches are where they are at.
Dialogue: 0,0:07:57.00,0:08:01.00,Default,,0000,0000,0000,,Now let me continue the air journey because \NI wanna make sure we finish it off.
Dialogue: 0,0:08:01.00,0:08:05.00,Default,,0000,0000,0000,,So let's say we take a little branch like that, we expand it.
Dialogue: 0,0:08:05.00,0:08:09.00,Default,,0000,0000,0000,,We keep zooming into it, zooming into it, zooming into it,
Dialogue: 0,0:08:09.00,0:08:12.00,Default,,0000,0000,0000,,until it's microscopic, you cant see it \Nwith your eyes any more;
Dialogue: 0,0:08:12.00,0:08:16.00,Default,,0000,0000,0000,,but you could see it under a microscope. \NIt would look like this.
Dialogue: 0,0:08:16.00,0:08:21.00,Default,,0000,0000,0000,,It would basically in a microscope, \Nit would look like a bunch of little sacs like these.
Dialogue: 0,0:08:21.00,0:08:27.00,Default,,0000,0000,0000,,And these sacs, we call these alveoli. Alveoli.
Dialogue: 0,0:08:27.00,0:08:30.00,Default,,0000,0000,0000,,And the air, it actually kind of runs into the alveoli.
Dialogue: 0,0:08:30.00,0:08:34.00,Default,,0000,0000,0000,,It has a dead end and then it comes back around.
Dialogue: 0,0:08:34.00,0:08:37.00,Default,,0000,0000,0000,,And then you breathe it out. So that's how breathing works.
Dialogue: 0,0:08:37.00,0:08:42.00,Default,,0000,0000,0000,,The air goes all the way from the mouth down \Nto the alveoli, takes a U-turn and it goes back out.
Dialogue: 0,0:08:42.00,0:08:49.00,Default,,0000,0000,0000,,But before it does that, before it leaves-\NVery close to the alveoli is blood.
Dialogue: 0,0:08:49.00,0:08:55.00,Default,,0000,0000,0000,,Let's say blood is coming this way and going that way, \Nand what will happen is that,
Dialogue: 0,0:08:55.00,0:08:58.00,Default,,0000,0000,0000,,actually out of the or into the blood, let's do that first.
Dialogue: 0,0:08:58.00,0:09:05.00,Default,,0000,0000,0000,,We've got oxygen, oxygen will actually go into the blood, and out of the blood will be waste.
Dialogue: 0,0:09:05.00,0:09:09.00,Default,,0000,0000,0000,,So you'll have some carbon dioxide waste \Nthat your cells have been making.
Dialogue: 0,0:09:09.00,0:09:14.00,Default,,0000,0000,0000,,And that waste actually then \Ngets thrown back into the alveoli.
Dialogue: 0,0:09:14.00,0:09:18.00,Default,,0000,0000,0000,,So now you can see how oxygen \Ngets from the outside world,
Dialogue: 0,0:09:18.00,0:09:21.00,Default,,0000,0000,0000,,gets breathed into the lungs when you inhale,
Dialogue: 0,0:09:21.00,0:09:25.00,Default,,0000,0000,0000,,gets down into the alveoli, exchanges with the blood;
Dialogue: 0,0:09:25.00,0:09:28.00,Default,,0000,0000,0000,,and then you exhale and let all that carbon dioxide out.