1 00:00:01,000 --> 00:00:04,000 Let's say that this is you. You're enjoying a nice sunny day 2 00:00:04,000 --> 00:00:09,000 and you decided to take a nice long deep breath of air. 3 00:00:09,000 --> 00:00:15,000 And of course when I say air the part that you probably care the most about is just the oxygen, 4 00:00:15,000 --> 00:00:21,000 part of that air, that's the part that we as humans need to survive. 5 00:00:21,000 --> 00:00:24,000 So you take a deep breath. Let's say you take it through your mouth, 6 00:00:24,000 --> 00:00:26,000 you take a deep breath through your mouth. 7 00:00:26,000 --> 00:00:30,000 And then lets say you take one more deep breath, a second deep breath, 8 00:00:30,000 --> 00:00:31,000 and then you take that one through your nose. 9 00:00:31,000 --> 00:00:36,000 And you might think, well, these are two totally different ways of getting in air, 10 00:00:36,000 --> 00:00:40,000 that's certainly how it looks when you look at the mouth and nose, 11 00:00:40,000 --> 00:00:42,000 they don't look like they have much in common. 12 00:00:42,000 --> 00:00:45,000 But the truth is that actually if you follow the air, 13 00:00:45,000 --> 00:00:50,000 it almost follows an identical path. 14 00:00:50,000 --> 00:00:56,000 The air is going into the back of the throat really regardless of how you took it in. 15 00:00:56,000 --> 00:00:59,000 So here we have air coming in from the nose, 16 00:00:59,000 --> 00:01:03,000 in here yet air coming in from the mouth and they meet up in the back of throat. 17 00:01:03,000 --> 00:01:10,000 And then they go down down down, they go towards this thing that we call the Adam's apple. 18 00:01:10,000 --> 00:01:14,000 I'm gonna bring it up a little bit, you can see it more easily. 19 00:01:14,000 --> 00:01:19,000 But basically you bring up this, you see this Adam's apple right there. 20 00:01:19,000 --> 00:01:22,000 And actually you can go ahead and take a feel of you own Adam's apple. 21 00:01:22,000 --> 00:01:27,000 It's a pretty cool structure in the middle of your throat 22 00:01:27,000 --> 00:01:30,000 and everybody has it, that's the first thing I want to tell you, 23 00:01:30,000 --> 00:01:34,000 that everybody has it, not just in men, women have it too. 24 00:01:34,000 --> 00:01:41,000 And the reason it's called an Adam's apple is because Adam is generally a boy's name. 25 00:01:41,000 --> 00:01:49,000 And so it's to remind us that usually men or boys have larger Adam's apples than girls. 26 00:01:49,000 --> 00:01:54,000 And if youre trying to find it, I also want to point that its a notch here. 27 00:01:54,000 --> 00:01:57,000 And you if you can feel the notch with your fingers, 28 00:01:57,000 --> 00:02:00,000 in that case you have a nice clue as to where it is located. 29 00:02:00,000 --> 00:02:06,000 This is Adam's apple and what it does is, it helps you control your voice. 30 00:02:06,000 --> 00:02:08,000 And actually theres another name for Adam's apple. 31 00:02:08,000 --> 00:02:13,000 Another name for it, sometimes people call it the voice box. The voice box. 32 00:02:13,000 --> 00:02:21,000 And of course air passing through the voice box in this kind of the entry way into the trachea. 33 00:02:21,000 --> 00:02:28,000 And so it actually allows me to make my voice very high or make my voice very low, 34 00:02:28,000 --> 00:02:34,000 depending on how you change the muscles around in that Adam's apple. 35 00:02:34,000 --> 00:02:39,000 So that's actually kind of a first cool thing I want to point out to you, that you can actually control your voice. 36 00:02:39,000 --> 00:02:44,000 I'm sure you knew this already but what youre using is the Adam's apple, your voice box. 37 00:02:44,000 --> 00:02:49,000 Now air keeps going, air is just gonna keeps making its journey down and 38 00:02:49,000 --> 00:02:54,000 specifically of course the part of air I said, you know, we care about is the oxygen. 39 00:02:54,000 --> 00:02:58,000 Its gonna keep making its journey down into the lung areas, 40 00:02:58,000 --> 00:03:05,000 now the lung areas, it's gone down the trachea and it goes into the two lungs, the right and left lungs. 41 00:03:05,000 --> 00:03:11,000 This is the left lung, I'm gonna put L for left and this is the right lung, I'll put R for right. 42 00:03:11,000 --> 00:03:14,000 And immediately you'll think, "Wait a second, aren't they switched?" 43 00:03:14,000 --> 00:03:19,000 Now I want you to remember that this is from the perspective of the person who owns the lungs. 44 00:03:19,000 --> 00:03:23,000 So that's why I put it in left where I put it, in right where I put it. 45 00:03:23,000 --> 00:03:26,000 Now we should probably go ahead and start labeling some of these. 46 00:03:26,000 --> 00:03:30,000 You can see that the lungs actually don't look identical, right? 47 00:03:30,000 --> 00:03:34,000 They look slightly different, for example, this one has three lobes. 48 00:03:34,000 --> 00:03:40,000 The right side has three lobes called the upper lobe, middle lobe and lower lobe. 49 00:03:40,000 --> 00:03:45,000 And the left one only has two lobes, that's the first kind of a big difference. 50 00:03:45,000 --> 00:03:53,000 And the other difference is that you actually have this thing in the middle that we call a cardiac notch. 51 00:03:53,000 --> 00:03:57,000 This thing right here, this is called the cardiac notch. 52 00:03:57,000 --> 00:04:03,000 And the reason we call it that is that it's a little spot that gets formed 53 00:04:03,000 --> 00:04:07,000 because the heart is literally kind of peeking out here. 54 00:04:07,000 --> 00:04:11,000 And as a result it's kind of makes a notch in the lung where it develops. 55 00:04:11,000 --> 00:04:15,000 So the heart takes a little space here, this is the heart. 56 00:04:15,000 --> 00:04:22,000 And as a result, it takes or makes that notch. So this is our heart space there. 57 00:04:22,000 --> 00:04:27,000 So on the other side you've got of course your two lobes, your upper and lower lobes. 58 00:04:27,000 --> 00:04:31,000 And these are exclusive, you see a lung just kind of sitting by itself. 59 00:04:31,000 --> 00:04:36,000 And you want to figure out whether its the left lung or the right lung, 60 00:04:36,000 --> 00:04:40,000 you can look for the lobes, the number of lobes, or you can look for that cardiac notch. 61 00:04:40,000 --> 00:04:45,000 Now around here, around these lungs, you've got ribs. 62 00:04:45,000 --> 00:04:52,000 You've got ribs here and between the ribs you've got rib muscles and of course on both sides. 63 00:04:52,000 --> 00:04:59,000 And below the lungs and below the heart, you've got a muscle, a big muscle. 64 00:04:59,000 --> 00:05:05,000 Actually it's gonna come through here, I'm just gonna kind of go through the word heart, 65 00:05:05,000 --> 00:05:08,000 and it basically becomes the floor. 66 00:05:08,000 --> 00:05:14,000 So the heart and the two lungs sit on this floor that made up of this muscle 67 00:05:14,000 --> 00:05:21,000 and this muscle is the diaphragm muscle, so this diaphragm muscle makes up the floor. 68 00:05:21,000 --> 00:05:26,000 The ribs make up the walls, so what do we have? 69 00:05:26,000 --> 00:05:32,000 We have basically a room, we have a giant room with walls and the floor. 70 00:05:32,000 --> 00:05:36,000 And this entire room we actually call the thorax. 71 00:05:36,000 --> 00:05:40,000 So within this room then you have your two lungs and your heart. 72 00:05:40,000 --> 00:05:46,000 So, so far so good, but I haven't done a very nice job of actually showing you where the air goes. 73 00:05:46,000 --> 00:05:51,000 I just kind of pointed that it goes to the two lungs, we don't have to get to see where it goes after that. 74 00:05:51,000 --> 00:05:53,000 So let me actually, I'm gonna erase a lot of these. 75 00:05:53,000 --> 00:05:59,000 I'm gonna reveal to you what it would look like if you could slip on some X-ray glasses 76 00:05:59,000 --> 00:06:03,000 and look into your two lungs, this is kind of what it would look like. 77 00:06:03,000 --> 00:06:11,000 You've got all these interesting architecture and the easiest way to kind of think about this, 78 00:06:11,000 --> 00:06:14,000 probably the simplest way to think about this, is to imagine a tree, 79 00:06:14,000 --> 00:06:19,000 to imagine a tree, and that tree has been flipped upside down, 80 00:06:19,000 --> 00:06:24,000 so you've got all these branches of that tree and they are branching and branching. 81 00:06:24,000 --> 00:06:31,000 And if you flip this tree upside down, you start seeing that it looks a lot like what we have in our lungs. 82 00:06:31,000 --> 00:06:37,000 Our lungs basically look like a flipped up or a flipped upside down tree and we even call that, 83 00:06:37,000 --> 00:06:42,000 we even call this entire structure, we call it a bronchial tree. 84 00:06:42,000 --> 00:06:47,000 So when you look at the lungs and they look kind of messier and complicated. 85 00:06:47,000 --> 00:06:52,000 Just think of them as an upside down bronchial tree and all of a sudden 86 00:06:52,000 --> 00:06:57,000 it'll look much simpler with basically in the middle you've got this nice trunk, 87 00:06:57,000 --> 00:07:01,000 this is our trunk, and then it's kind of branching from there. 88 00:07:01,000 --> 00:07:06,000 So air goes down this main trunk, this trachea, and they kind of start splitting up. 89 00:07:06,000 --> 00:07:12,000 And each of this kind of colored regions, the green region and the purple region serve a different lobe. 90 00:07:12,000 --> 00:07:18,000 So this green region serves the lower lobe down here, the purple serves the upper lobe. 91 00:07:18,000 --> 00:07:23,000 And on this side, you've got an upper, a middle and a lower lobe. 92 00:07:23,000 --> 00:07:25,000 Now I know it looks a little bit strange because 93 00:07:25,000 --> 00:07:30,000 you've got some green branches in what should be the middle lobe like right here. 94 00:07:30,000 --> 00:07:34,000 You've got some orange branches in what looks like the upper lobe like right there. 95 00:07:34,000 --> 00:07:39,000 But what you have to remember, this is kind of tricky, just try to play it in you head, 96 00:07:39,000 --> 00:07:45,000 what you have to remember is that, what you have is basically a three dimensional lung. 97 00:07:45,000 --> 00:07:48,000 So you have to imagine that we are literally looking at the front side 98 00:07:48,000 --> 00:07:52,000 but of course that middle lobe does go back. 99 00:07:52,000 --> 00:07:57,000 And if you went back then youd make perfect sense why the orange branches are where they are at. 100 00:07:57,000 --> 00:08:01,000 Now let me continue the air journey because I wanna make sure we finish it off. 101 00:08:01,000 --> 00:08:05,000 So let's say we take a little branch like that, we expand it. 102 00:08:05,000 --> 00:08:09,000 We keep zooming into it, zooming into it, zooming into it, 103 00:08:09,000 --> 00:08:12,000 until its microscopic, you cant see it with your eyes anymore. 104 00:08:12,000 --> 00:08:16,000 But you could see it under a microscope. It would look like this. 105 00:08:16,000 --> 00:08:21,000 It would basically in a microscope, it would look like a bunch of little sacs like these. 106 00:08:21,000 --> 00:08:27,000 And these sacs, we call these alveoli. Alveoli. 107 00:08:27,000 --> 00:08:30,000 And the air, it actually kind of runs into the alveoli. 108 00:08:30,000 --> 00:08:34,000 It has a dead end and then it comes back around. 109 00:08:34,000 --> 00:08:37,000 And then you breathe it out. So that's how breathing works. 110 00:08:37,000 --> 00:08:42,000 The air goes all the way from the mouth down to the alveoli, takes a U-turn and it goes back out. 111 00:08:42,000 --> 00:08:49,000 But before it does that, before it leaves, very close to the alveoli is blood. 112 00:08:49,000 --> 00:08:55,000 Let's say blood is coming this way and going that way, and what will happen is that, 113 00:08:55,000 --> 00:08:58,000 actually out of the or into the blood, let's do that first. 114 00:08:58,000 --> 00:09:05,000 We've got oxygen, oxygen will actually go into the blood, and out of the blood will be waste. 115 00:09:05,000 --> 00:09:09,000 So you'll have some carbon dioxide waste that your cells have been making. 116 00:09:09,000 --> 00:09:14,000 And that waste actually then gets thrown back into the alveoli. 117 00:09:14,000 --> 00:09:18,000 So now you can see how the oxygen gets from the outside world, 118 00:09:18,000 --> 00:09:21,000 gets breathed into the lungs when you inhale, 119 00:09:21,000 --> 00:09:25,000 gets down into the alveoli, exchanges with the blood. 120 00:09:25,000 --> 00:09:28,000 And then you exhale and let all that carbon dioxide out.