WEBVTT - Selects: Does the body replace itself? 0:00:00.760 --> 0:00:03.880 Hey, everybody, it's your old pal Josh for this week's select. 0:00:03.920 --> 0:00:07.400 I've chosen Does the body replace itself every seven years? 0:00:07.840 --> 0:00:10.000 Sounds like a medical episode, and it kind of is. 0:00:10.280 --> 0:00:12.720 But after a little while it turns into a brainbuster 0:00:12.800 --> 0:00:15.840 of a head scratcher of a philosophical bent that I 0:00:15.880 --> 0:00:18.880 think you're gonna love. I hope you enjoy the living. 0:00:18.840 --> 0:00:19.599 Heck out of it. 0:00:24.200 --> 0:00:29.920 Welcome to Stuff you Should Know, a production of iHeartRadio. 0:00:33.640 --> 0:00:36.120 Hey, and welcome to the podcast. I'm Josh Clark with 0:00:36.240 --> 0:00:39.159 Charles W. Chuck Bryant and guest producer. 0:00:38.840 --> 0:00:41.640 Nol Knowle's in the house. 0:00:41.880 --> 0:00:44.920 It's the it in the new studio. Yeah, man, this 0:00:45.040 --> 0:00:47.199 place is comfy, cozy. I like it. 0:00:47.240 --> 0:00:49.920 I wish I'm I don't know, I wish there was 0:00:49.960 --> 0:00:52.160 a chair version of a waterbed. 0:00:52.240 --> 0:00:54.800 I know this is a napish little place. 0:00:54.920 --> 0:00:58.600 Yeah, especially today, I think I'm dragging all apologies. 0:00:59.320 --> 0:01:01.960 Yeah, same here. So if we're talking kind of slow 0:01:02.160 --> 0:01:05.319 or low, or we just stopped talking for a little while, 0:01:05.360 --> 0:01:07.039 it's we're as tired. 0:01:07.800 --> 0:01:10.080 Yeah, bumped into you at the Hawks game last night. 0:01:10.160 --> 0:01:11.600 I know, Hey, how many is that? 0:01:11.680 --> 0:01:14.640 You know? Yeah, just at the bump in yep. 0:01:15.080 --> 0:01:16.840 We were both at the Hawks gaming and the Hawks. 0:01:16.840 --> 0:01:19.800 One didn't even know we were going. Look over in line, 0:01:20.000 --> 0:01:24.200 there's Josh and Yumi. Yeah that's great. There's Chuck and Eddie. 0:01:24.480 --> 0:01:30.880 Yep in an arena of eighteen thousand bumping into someone? 0:01:31.080 --> 0:01:31.520 Is that it? 0:01:31.560 --> 0:01:32.400 That's all it holds? 0:01:32.680 --> 0:01:35.280 I think it's something like that. It's a good lot 0:01:35.280 --> 0:01:35.640 of people. 0:01:35.680 --> 0:01:36.400 It's a good arena. 0:01:36.560 --> 0:01:38.400 Yeah. But you had box seats because you're special. 0:01:38.720 --> 0:01:40.720 They were free out. 0:01:40.800 --> 0:01:42.600 Mine were free to in. The nose bleeds. 0:01:43.560 --> 0:01:45.400 I liked just about every seat in that place. 0:01:45.520 --> 0:01:46.720 Yeah, it's not too bad. I was. 0:01:46.800 --> 0:01:50.720 I was laughing about the nosebleeds going in, But then 0:01:50.720 --> 0:01:51.200 I got up there. 0:01:51.240 --> 0:01:53.560 I was like, this is great. Yeah you can see everything. 0:01:53.640 --> 0:01:56.200 Did you nose actually bleed just twice? 0:01:56.440 --> 0:02:00.840 Yeah, once out of its sheer excitement and then once 0:02:00.960 --> 0:02:03.560 from the altitude and that was more of a spray, 0:02:03.840 --> 0:02:05.720 rightah yeah. 0:02:05.000 --> 0:02:07.760 Just covering everyone that was like go Hawks. 0:02:08.720 --> 0:02:09.680 Boy, what a weird intro. 0:02:09.919 --> 0:02:12.480 It's a little weird, but I mean it kind of 0:02:13.040 --> 0:02:17.920 jibes a little bit because we're talking. Yeah you're mentioning blood. 0:02:18.040 --> 0:02:20.320 Sure, it was shedding cells and blood. 0:02:20.400 --> 0:02:23.040 You were like, blood is made up of cells and 0:02:23.080 --> 0:02:26.240 we shed tons of cells. But before we get to that, right, 0:02:26.280 --> 0:02:30.600 there's the fact that the podcast you shed cells. I 0:02:30.639 --> 0:02:33.079 want to mention this one thing I read. Yeah, it's 0:02:33.120 --> 0:02:36.000 called I think the title of the article is the 0:02:36.120 --> 0:02:38.520 Self is Moral. It's about like where we get our 0:02:38.560 --> 0:02:42.400 identity of self from, like where it's rooted. It was 0:02:42.440 --> 0:02:45.519 written by a person named Nina Stromyer. I believe it 0:02:45.560 --> 0:02:48.120 was on AON magazine. Yeah, just type in the self 0:02:48.200 --> 0:02:50.840 is Moral aon it'll come up. 0:02:50.840 --> 0:02:51.560 I'll get you there. 0:02:52.040 --> 0:02:58.960 Uh. And towards the beginning, the author says, there's this 0:02:59.280 --> 0:03:03.040 very famous philosophical exercise, which you know, philosophers love to do, 0:03:03.080 --> 0:03:04.320 like mental exercises. 0:03:04.440 --> 0:03:06.000 Yeah, that's what that's all they hashened. 0:03:06.120 --> 0:03:10.120 So imagine you have like a kind of imagine you 0:03:10.200 --> 0:03:13.360 have like a ship, right, like a boat. Yeah, a 0:03:13.480 --> 0:03:19.280 nice Yankee clipper, okay, okay. And this Yankee clipper is slowly, 0:03:19.360 --> 0:03:23.520 over time kind of salvage for parts. But rather than 0:03:23.600 --> 0:03:26.040 just being stripped, like every time a part is taken out, 0:03:26.480 --> 0:03:30.040 it's replaced, and then over the course of like fifty 0:03:30.080 --> 0:03:33.480 one hundred years, is each plank, as each bolt, as 0:03:33.520 --> 0:03:37.800 each like mast head, even the thing. The carved lady 0:03:37.880 --> 0:03:41.640 in front eventually just gets replaced with something else. 0:03:41.720 --> 0:03:44.600 Yeah, a new carved lady that speaks of the time. 0:03:44.840 --> 0:03:48.640 Right, you know? Is it still though, after every single 0:03:48.640 --> 0:03:51.800 part has been replaced, the same ship that it was before? 0:03:52.960 --> 0:03:55.440 Yeah? I see what you mean. I don't think that 0:03:55.520 --> 0:03:56.640 can be possible. 0:03:58.560 --> 0:04:01.440 Why not, especially if it has the same name and 0:04:01.480 --> 0:04:03.840 it's the same ship in the same place as before. 0:04:03.960 --> 0:04:08.760 It was just slowly, over time moved out. True, where 0:04:08.760 --> 0:04:09.880 does the self lie? 0:04:10.320 --> 0:04:13.320 Yeah, that's a good point, man, Like redoing a house, 0:04:13.320 --> 0:04:15.480 same thing, Yeah, I mean, like they saw the floors 0:04:15.480 --> 0:04:18.040 and the walls and the windows, Like, when does it 0:04:18.080 --> 0:04:21.240 cease to become that same house that was built in 0:04:21.360 --> 0:04:22.640 nineteen thirty exactly. 0:04:22.680 --> 0:04:23.240 Isn't that cool? 0:04:23.360 --> 0:04:24.240 Yeah? It is really cool. 0:04:24.240 --> 0:04:26.560 And the reason that it applies to this episode is because, 0:04:26.680 --> 0:04:32.000 over the course of your lifetime, a significant portion, pretty 0:04:32.040 --> 0:04:35.200 much all of the cells in your body are going 0:04:35.279 --> 0:04:41.120 to be replaced. Yeah, so that the person even after 0:04:41.160 --> 0:04:46.279 you reach your adult self. Yeah, physically, by the time 0:04:46.279 --> 0:04:51.240 you die, assuming you're gonna die much later, you are 0:04:51.480 --> 0:04:54.560 essentially a different person, at least on the cellular level. 0:04:55.400 --> 0:04:58.080 Yeah, thirty seven trillion cells. 0:04:58.880 --> 0:04:59.880 Ish that's how many we have. 0:05:00.400 --> 0:05:03.119 Yeah, that's what they estimate. And I did a little 0:05:03.160 --> 0:05:03.839 looking into. 0:05:03.680 --> 0:05:06.720 Lifespans, like an estimate. 0:05:07.080 --> 0:05:09.240 Thirty seven trillion. Yeah, what do you want like to 0:05:09.520 --> 0:05:10.240 like give or take? 0:05:10.560 --> 0:05:14.200 Yeah, I did a little research into lifespans just because 0:05:14.200 --> 0:05:19.200 this all sort of comes back to like your death basically, 0:05:19.320 --> 0:05:23.240 because that's all death is, is your your cells, you know, 0:05:23.800 --> 0:05:25.799 dying little by little. 0:05:26.240 --> 0:05:28.400 Well yeah, I mean if you think about it, Chuck, 0:05:28.440 --> 0:05:29.360 one of the things that. 0:05:29.600 --> 0:05:30.440 Like why do we die? 0:05:30.520 --> 0:05:33.520 If our we'll get to all that, Oh okay, but 0:05:33.560 --> 0:05:36.080 it's intriguing, you know it is it started, you know, 0:05:36.760 --> 0:05:39.880 questions started popping up. So apparently we gained about three 0:05:39.920 --> 0:05:45.480 months every three months of life humanity every year that 0:05:45.520 --> 0:05:48.560 we progress. 0:05:47.440 --> 0:05:50.640 Like the average life span spans by three months. 0:05:50.720 --> 0:05:52.680 Yeah, Like if you were born in twenty twelve, the 0:05:52.720 --> 0:05:55.360 average lifespan is now and this is the United States, 0:05:55.480 --> 0:05:57.960 is seventy eight point eight. If you were born in 0:05:58.040 --> 0:06:00.760 nineteen oh one, it was about forty seven and fifty 0:06:00.839 --> 0:06:04.240 years for men and women respectively. But if you look 0:06:04.320 --> 0:06:07.360 at the ratio, it's still about three months. Despite all 0:06:07.400 --> 0:06:13.200 our technologies, three months a year, every year, every year. 0:06:13.240 --> 0:06:14.479 Just slowly creeping along. 0:06:14.600 --> 0:06:16.840 Yeah, because I think the article it was like when 0:06:16.880 --> 0:06:19.040 we're going to live to be one hundred by average, 0:06:19.040 --> 0:06:21.240 and they say by the year twenty one hundred, if 0:06:21.240 --> 0:06:25.160 things hold, then the average human or American will be 0:06:25.240 --> 0:06:26.360 about one hundred years old. 0:06:26.520 --> 0:06:29.120 I thought that, so I guess that will if things 0:06:29.120 --> 0:06:32.560 are steadily progressing. I had heard that like our generation 0:06:32.680 --> 0:06:36.680 would be either the last or the first, the last 0:06:36.760 --> 0:06:41.760 to not hit triple digits or the first two on average. Yeah. 0:06:41.880 --> 0:06:44.320 Yeah, I guess these are all gases, you know, so 0:06:44.360 --> 0:06:51.000 who knows. Plus if you believe in like things speeding science, 0:06:51.000 --> 0:06:51.520 speeding up? 0:06:51.560 --> 0:06:52.760 Yeah, what is that? Moore's law? 0:06:53.160 --> 0:06:56.080 Yeah? Is that it? Yeah, applied to computers, so in 0:06:56.080 --> 0:06:56.760 that case. 0:06:56.560 --> 0:07:00.599 Right, right, but I mean you cantend it other stuff. 0:07:00.680 --> 0:07:02.680 Yeah, then you might think, you know it's it's but 0:07:03.480 --> 0:07:05.640 you know, they say it's not increasing like that. 0:07:06.279 --> 0:07:07.440 No, at least not so far. 0:07:07.600 --> 0:07:10.800 Moore's law is exponential growth just adding three months every 0:07:10.920 --> 0:07:15.440 year's yeah, non exponentials geometric. I think we're still at 0:07:15.440 --> 0:07:20.400 non exponential growth definitely. Yeah, we're just adding three months. Yeah, 0:07:20.400 --> 0:07:23.520 it's not bad though, that's pretty good average every four years. 0:07:23.520 --> 0:07:26.000 It's an extra year, yeah, well, and it's interesting to 0:07:26.040 --> 0:07:28.720 think about. You know, people that were born you know, 0:07:28.760 --> 0:07:32.080 a lot of our colleagues like eight years behind us, 0:07:32.840 --> 0:07:34.440 are going to live an average of. 0:07:34.400 --> 0:07:35.120 Two years longer. 0:07:36.160 --> 0:07:39.200 Yeah, that seems unfair, sad. 0:07:39.320 --> 0:07:41.440 Yeah, I know, what did they do to. 0:07:41.320 --> 0:07:47.240 Observe that we're we're thinking about our own deaths today? Yeah, 0:07:47.280 --> 0:07:53.760 and chuck that there's this rumor theory, legend maybe okay, 0:07:54.080 --> 0:07:58.480 that your body regenerates itself ninety percent of your body 0:07:58.520 --> 0:07:59.920 regenerates itself every year. 0:08:01.360 --> 0:08:02.240 Yeah that's not true. 0:08:02.320 --> 0:08:04.200 No, it's not true, but it was a very long 0:08:04.240 --> 0:08:07.080 standing rumor, and it was actually based on science. Yeah, 0:08:07.480 --> 0:08:10.360 you know, not just the idea that, oh yeah, ourselves regenerate. 0:08:10.440 --> 0:08:14.000 So back of the envelope estimate is that, you know, 0:08:14.080 --> 0:08:16.640 we regenerate ninety five or ninety eight percent of ourselves 0:08:16.640 --> 0:08:23.760 every year. It was early experimentation by injecting radioactive isotopes 0:08:23.800 --> 0:08:26.840 into human beings, yeah, and then following their course and 0:08:26.880 --> 0:08:30.320 then making estimates based on that led to this idea. 0:08:30.440 --> 0:08:33.400 It's called pulse labeling, is it. It's like tagging an 0:08:33.400 --> 0:08:35.240 animal in the wild basically. 0:08:34.920 --> 0:08:36.520 Right, but you're just tagging a cell. 0:08:36.800 --> 0:08:37.040 Yeah. 0:08:37.040 --> 0:08:38.280 The specific types of cells. 0:08:38.360 --> 0:08:40.959 Yeah, they don't do that to humans anymore. No, it's 0:08:41.080 --> 0:08:42.959 very animals. I think it's a very dumb thing to do. 0:08:43.320 --> 0:08:45.360 Sure, injecting radiation exactly. 0:08:45.440 --> 0:08:50.520 Yeah, unless, of course, you know it's radiation treatment that's true, 0:08:50.559 --> 0:08:52.200 which is still a really weird thing if you think 0:08:52.240 --> 0:08:52.640 about it. 0:08:52.640 --> 0:08:54.440 It's Yeah. I have a feeling it's gonna be like 0:08:54.440 --> 0:08:55.800 one of the things we look back on. 0:08:56.240 --> 0:08:59.160 As like a primitive treatment. Yeah, yeah, yeah, I hope so. 0:09:00.760 --> 0:09:03.959 But there was this long standing science for decades or 0:09:04.000 --> 0:09:08.720 this idea, scientific idea that we regenerated ourselves by ninety 0:09:08.760 --> 0:09:11.680 five ninety eight percent. Finally, and I think two thousand 0:09:11.679 --> 0:09:20.040 and five there was a a researcher named doctor Jonas Friesen. 0:09:20.559 --> 0:09:21.320 He's Swedish. 0:09:21.559 --> 0:09:22.200 Dude's awesome. 0:09:22.920 --> 0:09:26.800 He said, this whole urban legend is really bringing me down. 0:09:27.280 --> 0:09:31.280 I want to figure out a way to really track 0:09:31.880 --> 0:09:35.080 how often the human body regenerates itself. 0:09:35.520 --> 0:09:40.520 Yeah, and the biggest question has been the brain, specifically 0:09:40.800 --> 0:09:45.120 the cerebral cortex and the heart and the heart muscles. 0:09:45.360 --> 0:09:47.240 I mean, they want to know all this stuff, but 0:09:47.240 --> 0:09:48.640 those were the two biggest mysteries. 0:09:48.679 --> 0:09:51.000 I think, right, there's still the mysteries, but if you 0:09:51.040 --> 0:09:53.319 went back to prior to two thousand and five, in 0:09:53.400 --> 0:09:56.400 doctor Friesan's research, it was all a mystery. Yeah, he 0:09:56.520 --> 0:10:00.600 figured out. He basically put a very act curate time 0:10:00.679 --> 0:10:05.720 stamp on how often human tissue and human cells regenerate themselves. Right, 0:10:06.120 --> 0:10:09.559 So the way he did this is very clever. For 0:10:10.679 --> 0:10:15.560 a long time, botanists knew that the trees around the 0:10:15.600 --> 0:10:20.880 world contained a spike of carbon fourteen radiation. 0:10:21.000 --> 0:10:23.880 Yes, thanks to humans and nuclear bombs. 0:10:23.960 --> 0:10:27.400 Exactly from nineteen fifty four to nineteen sixty three, tree 0:10:27.480 --> 0:10:32.040 rings for tree growth around the world show a big 0:10:32.080 --> 0:10:35.960 spike in carbon fourteen. Carbon fourteen is naturally occurring too, 0:10:36.760 --> 0:10:40.400 So like just cosmic rays from the sun bombarred Earth's 0:10:40.440 --> 0:10:46.440 atmosphere and create radioactive isotopes by knocking electrons from particles 0:10:46.440 --> 0:10:53.360 in Earth's atmosphere, right, those radioactive particles become carbon fourteen, 0:10:53.679 --> 0:10:57.560 which is radioactive, and in the atmosphere, carbon fourteen binds 0:10:57.600 --> 0:11:02.160 to oxygen and creates carbon dioxide, which comes to Earth. 0:11:02.559 --> 0:11:06.640 Every living thing breathes this stuff in, whether it's a plant, 0:11:06.920 --> 0:11:10.840 whether it's a human like we just have see fourteen 0:11:10.960 --> 0:11:11.720 in our bodies. 0:11:11.840 --> 0:11:15.360 We also eat plants exactly contain the sea fourteen besides 0:11:15.400 --> 0:11:15.920 breathing it in. 0:11:15.960 --> 0:11:18.040 And we also eat the animals that eat the plants 0:11:18.080 --> 0:11:22.360 that in just see fourteen. Right, So like we got 0:11:22.480 --> 0:11:28.000 carbon fourteen in our bodies, that's right. But because of 0:11:28.080 --> 0:11:31.079 the spike in carbon fourteen that was introduced to the 0:11:31.280 --> 0:11:38.280 atmosphere from nuclear testing, there is a spike in humans 0:11:38.320 --> 0:11:41.200 as well. So you can roughly age like a human 0:11:41.400 --> 0:11:45.920 compared to another human if they were born in say 0:11:46.240 --> 0:11:48.920 nineteen fifty nine, and one who was born in nineteen 0:11:48.960 --> 0:11:52.720 seventy after there was that spike of carbon fourteen had 0:11:52.720 --> 0:11:56.640 gone away. Right, that's pretty cool. But what doctor Friesen 0:11:56.720 --> 0:11:59.960 did is even cooler. He basically went back to those 0:12:00.080 --> 0:12:03.120 tree trunks, those tree rings that show a spike in 0:12:03.200 --> 0:12:09.880 carbon fourteen, and created a calendar of carbon fourteen decay 0:12:10.120 --> 0:12:15.400 and basically said, okay, on this date, this is how 0:12:15.480 --> 0:12:20.080 much carbon fourteen was on Earth. And if I take 0:12:20.160 --> 0:12:23.560 this cell and compare it, knowing that carbon fourteen decays 0:12:23.600 --> 0:12:27.120 at a constant rate, I can tell you exactly how 0:12:27.120 --> 0:12:31.040 old this cell is exactly. And he used it to 0:12:31.200 --> 0:12:34.240 date cells and tissues and all sorts of cool stuff. 0:12:34.320 --> 0:12:37.480 Yeah, he was He went looking for a marker, and 0:12:37.559 --> 0:12:41.680 he found one due to our atomic testing program, which 0:12:41.720 --> 0:12:44.679 is pretty weird. You just released all that junk in 0:12:44.720 --> 0:12:47.640 the atmosphere and now all these years later it has 0:12:47.640 --> 0:12:48.320 a nice use. 0:12:48.840 --> 0:12:50.240 Yeah, you know it does. 0:12:50.880 --> 0:12:52.880 So we now know when we're going to die, right 0:12:53.480 --> 0:12:55.640 sort of. And the reason he was able to use 0:12:55.679 --> 0:13:00.439 this as a marker, Chuckers, is that when you take a. 0:13:00.400 --> 0:13:03.440 Breath of life, your first breath of life, that's right, 0:13:04.040 --> 0:13:06.679 and you get some you get some of that C 0:13:06.840 --> 0:13:11.280 fourteen into your DNA, and a steady amount stays in there, 0:13:11.320 --> 0:13:14.280 like you don't keep ingesting C fourteen as far as 0:13:14.320 --> 0:13:17.439 I understand, as far as your DNA goes, Oh okay, 0:13:17.559 --> 0:13:22.040 once it's in your DNA, as your cells divide, that 0:13:22.200 --> 0:13:27.800 original amount becomes divided evenly. So the less C fourteen 0:13:27.840 --> 0:13:32.760 that's in tissue, the older that cell line is. Where 0:13:32.800 --> 0:13:36.640 then the younger the actual cells are. Right, Is that right? 0:13:36.960 --> 0:13:39.640 I think so, which would mean the new cell the 0:13:39.720 --> 0:13:42.959 marker would be a fresh batch of the C fourteen. 0:13:43.280 --> 0:13:45.280 No, it have less C fourteen. 0:13:45.440 --> 0:13:49.320 Oh really, yeah, let's say you have because the cell divided, yes, exactly, Yeah. 0:13:49.440 --> 0:13:52.880 Like you have ten grams of C fourteen, which you don't. 0:13:53.880 --> 0:13:56.240 I can't imagine what that would be. Like. Let's say 0:13:56.280 --> 0:13:59.520 your your one cell that's never divided has ten Yeah, 0:13:59.559 --> 0:14:02.320 when it into two, it's each of those two cells 0:14:02.440 --> 0:14:05.079 is going to have five grand and then two and 0:14:05.120 --> 0:14:07.160 a half, and then one point seventy five and so 0:14:07.200 --> 0:14:10.160 on and so on. So since you know that C 0:14:10.320 --> 0:14:13.160 fourteen is generated at a constant rate, you know that 0:14:13.200 --> 0:14:15.640 it decays at a half life of fifty seven hundred 0:14:15.679 --> 0:14:20.560 and thirty years, you can look at the amount of 0:14:21.480 --> 0:14:25.720 C fourteen and then also the decay of it as well. Yeah, 0:14:25.760 --> 0:14:27.800 you can date things that are no longer living too, 0:14:28.120 --> 0:14:31.560 to see when the when they ingested that C fourteen. 0:14:31.360 --> 0:14:33.760 Was Yeah, he's a little like a bingo card. He 0:14:33.880 --> 0:14:36.080 just from the calendar that he made with the trees, 0:14:36.520 --> 0:14:38.400 and he holds it up in the light, and that's 0:14:38.440 --> 0:14:39.440 how he determines it. 0:14:39.280 --> 0:14:41.040 It's not true. 0:14:41.040 --> 0:14:44.240 But what he did determine though, was which is really cool, 0:14:44.400 --> 0:14:46.200 And this is sort of what we've been building toward, 0:14:46.440 --> 0:14:52.240 is that most of your cells are about seven to 0:14:52.240 --> 0:14:55.560 ten years old, yes, in the body, and there are variances, 0:14:55.560 --> 0:14:57.000 and of course we're going to talk about all that, 0:14:57.160 --> 0:15:00.600 and right after this break, we're going to give you 0:15:00.640 --> 0:15:01.840 a little primer on cells. 0:15:02.280 --> 0:15:03.360 So you know what all this means. 0:15:03.600 --> 0:15:27.960 Right, All right, Josh, were promised to sell primer, and 0:15:28.000 --> 0:15:29.640 we like to deliver on those promises. 0:15:29.960 --> 0:15:31.000 Here stuff you should know. 0:15:31.720 --> 0:15:34.960 So I guess we started off by saying there are 0:15:35.000 --> 0:15:39.200 thirty seven trillion cells about in the human body. Yeah, 0:15:39.240 --> 0:15:42.840 give or take, give or take, and water makes up 0:15:42.840 --> 0:15:43.640 about two thirds of. 0:15:43.600 --> 0:15:47.880 The weight of those cells. Oh yeah, that's right. They're tiny. 0:15:48.520 --> 0:15:51.480 You need a microscope to see them, and it's like 0:15:51.560 --> 0:15:53.720 it's the tiniest thing that can still reproduce. 0:15:54.000 --> 0:15:54.240 Yeah. 0:15:54.440 --> 0:15:57.000 And even though we have many different kinds of cells, 0:15:57.080 --> 0:16:01.640 I think two hundred types, and within those cells there 0:16:01.640 --> 0:16:04.440 are differences, but there are a lot of similarities with 0:16:04.520 --> 0:16:09.160 all cells in their structure. Namely, they have a cell membrane, 0:16:09.320 --> 0:16:11.360 they have a nucleus, have a nucleus, some have more 0:16:11.400 --> 0:16:15.320 than one. And these membranes are what allows nutrients to 0:16:15.360 --> 0:16:18.760 pass in and out, waste to pass out water through 0:16:18.800 --> 0:16:25.520 osmosis travels in reverse, osmosis travels out. 0:16:25.720 --> 0:16:27.240 Yeah. 0:16:27.480 --> 0:16:30.680 And what else, We got your mitochondria as well. That's 0:16:30.720 --> 0:16:33.720 where this is the important, really important thing, which is 0:16:33.920 --> 0:16:35.720 basically what keeps your cells alive. 0:16:35.960 --> 0:16:37.600 That's the power center, right. 0:16:37.480 --> 0:16:40.960 Yeah, and that's you know, your cells need food to 0:16:41.040 --> 0:16:43.720 live just like your body does. But you can't pass 0:16:43.800 --> 0:16:47.400 that that hamburger straight into your cell, right. It needs 0:16:47.440 --> 0:16:49.280 to be broken down so your cell can use. 0:16:49.160 --> 0:16:54.800 It exactly into what adenosne triphosphate ATP is like the 0:16:56.000 --> 0:16:58.320 universal cell fuel, right. 0:16:58.400 --> 0:16:58.720 Yeah. 0:16:58.840 --> 0:17:02.280 So there's a lot of stuff that the body does make. 0:17:02.440 --> 0:17:06.439 I think you need like twenty three I think you 0:17:06.480 --> 0:17:09.719 need twenty three amino acids, and like nine of them 0:17:09.800 --> 0:17:12.240 your body doesn't really manufacture. So those are the nine 0:17:12.280 --> 0:17:15.720 non essential amino acids, right. And you use amino acids 0:17:15.720 --> 0:17:20.520 to build proteins, and use proteins for everything from making muscles, 0:17:20.600 --> 0:17:25.840 to making red blood cells to you're mounting and immune response. 0:17:25.880 --> 0:17:29.760 Proteins are very very vital in some of them you 0:17:29.840 --> 0:17:32.760 have to build by eating stuff from your environment, right. 0:17:32.960 --> 0:17:33.400 Yeah. 0:17:33.520 --> 0:17:35.160 So you go out and you find yourself a nice 0:17:35.200 --> 0:17:38.359 pig and you cut off its back leg. You say, sorry, pig, 0:17:38.840 --> 0:17:41.880 here's a pig leg for you. But I need this leg. 0:17:42.200 --> 0:17:44.399 I'm gonna eat this leg. And what I'm really eating 0:17:44.440 --> 0:17:48.359 is the muscle. What I'm really really eating is the glutamine. Yeah, 0:17:48.440 --> 0:17:50.720 and in my body's going to take this glutamine. It 0:17:50.760 --> 0:17:52.679 can make it itself. But it doesn't hurt to have 0:17:52.720 --> 0:17:54.119 an extra little bit of glutamine. 0:17:54.160 --> 0:17:56.160 Yeah, it does to have that pig leg And you're 0:17:56.240 --> 0:17:57.160 exactly right. 0:17:57.280 --> 0:17:59.760 So I'm chomping on the pig legs. The pigs must 0:18:00.080 --> 0:18:02.679 and listeners by the way, right, just use your imagination 0:18:02.800 --> 0:18:07.159 for a second. Sure, And yes, I'm sorry too. So 0:18:07.240 --> 0:18:10.359 you're eating the pig like and you're gaining this glutamine 0:18:10.359 --> 0:18:13.240 as a result, and your body's metabolizing the glutamine and 0:18:13.240 --> 0:18:16.679 then reusing it, right, And it can be glutamine, it 0:18:16.720 --> 0:18:21.320 can be anything. If we're ingesting a protein, if we're 0:18:21.440 --> 0:18:25.359 ingesting amino acids, if we're eating any kind of food, sugars, whatever, 0:18:25.760 --> 0:18:29.000 our bodies break it down into its constituent parts, and 0:18:29.040 --> 0:18:32.959 then a lot of those constituent parts become part of 0:18:33.000 --> 0:18:37.480 our bodies. So if you think about it in this sense, 0:18:37.560 --> 0:18:41.560 when we eat, when we breathe, we're taking in stuff 0:18:41.600 --> 0:18:44.879 we need from the environment, and that stuff that we 0:18:45.000 --> 0:18:47.200 take in from the environment becomes a part of us 0:18:47.359 --> 0:18:50.960 literally physically on the molecular level, it becomes a part 0:18:50.960 --> 0:18:51.439 of us. 0:18:51.400 --> 0:18:53.400 For better or worse, depending on what it is. Of course. 0:18:53.520 --> 0:18:56.520 Yeah, that's a great I think that's ultimately one of 0:18:56.560 --> 0:18:59.160 the side lessons of this whole thing is we should 0:18:59.200 --> 0:19:03.199 take care of ourvironment because that environment becomes us and 0:19:03.240 --> 0:19:05.639 we either suffer or thrive as a result of it. 0:19:05.720 --> 0:19:07.480 You ever heard the expression you are what you eat? 0:19:07.920 --> 0:19:08.400 Exactly? 0:19:08.560 --> 0:19:09.720 Know, you literally are what. 0:19:09.640 --> 0:19:13.200 You eat, quite literally. And then also chuck, it goes 0:19:13.240 --> 0:19:17.120 the other way as well. When we excrete waste, when 0:19:17.160 --> 0:19:20.800 we exhale CO two that's taken up by other things 0:19:20.800 --> 0:19:23.399 in the environment, is deposited into the environment and it 0:19:23.440 --> 0:19:27.440 becomes part of the environment itself. So not only do 0:19:27.480 --> 0:19:33.800 we regenerate our cells, regenerate tissue on average seven to 0:19:33.840 --> 0:19:39.200 ten years, become almost wholly a new version of ourselves. 0:19:41.240 --> 0:19:46.560 Were also the boundary between us and the surrounding environment 0:19:47.200 --> 0:19:53.639 is really nonexistent because there's a constant exchange of molecules. 0:19:53.960 --> 0:19:57.159 Yeah, we lose on average, they say nine the average 0:19:57.160 --> 0:20:02.480 adult male loses ninety six million cells per minute, But 0:20:03.119 --> 0:20:07.760 we also replace those at the rate of ninety six 0:20:07.800 --> 0:20:09.679 million per minute, yeah roughly. 0:20:09.880 --> 0:20:12.280 Yeah. Yeah, so that's the good news. 0:20:12.440 --> 0:20:14.440 So we've got all these cells that we're losing. We've 0:20:14.440 --> 0:20:16.359 got all these new cells that are replacing them. And 0:20:16.520 --> 0:20:18.800 I think, like you said earlier before the break, that 0:20:19.840 --> 0:20:24.359 these the different types of cells and then hence different 0:20:24.440 --> 0:20:27.399 tissues regenerate at a different rate, right. 0:20:27.480 --> 0:20:30.760 Yeah, And they all have specialized jobs, and the cells 0:20:30.760 --> 0:20:34.000 are often built in such a way to aid that 0:20:34.119 --> 0:20:38.600 job physically, you know, different to make that job easier. 0:20:38.280 --> 0:20:41.040 Which is really cool too, right, shows how versatile they are. 0:20:42.119 --> 0:20:44.840 Yes, you know, like stem cells are very versatile. 0:20:45.080 --> 0:20:45.480 Super. 0:20:46.200 --> 0:20:51.200 So let's say your skin, Yeah, your skin regenerates every 0:20:51.760 --> 0:20:54.880 two to four weeks. I think, yeah, exactly, you get 0:20:54.920 --> 0:20:58.440 a new healthy coating of skin every two to four 0:20:58.480 --> 0:21:04.200 weeks because you're epithal cells are particularly good at regenerating themselves. 0:21:04.520 --> 0:21:07.960 That's right, And that is well, I guess that would 0:21:07.960 --> 0:21:11.760 fall on the low side, obviously, if we're talking seven 0:21:11.800 --> 0:21:14.560 to ten years. On the super low side, you have 0:21:14.600 --> 0:21:17.200 the cells that line like you're intestine in your gut, 0:21:17.920 --> 0:21:20.760 and those things don't last long at all because it's 0:21:20.800 --> 0:21:23.360 such a harsh environment. You know, you wouldn't expect them 0:21:23.359 --> 0:21:25.800 to last like weeks and months and years. 0:21:26.400 --> 0:21:27.920 I think, how long is it? Five days? 0:21:28.160 --> 0:21:29.720 Yeah, that's nothing but the. 0:21:29.680 --> 0:21:34.399 Structure of your guts that are beneath that membrane lining 0:21:34.440 --> 0:21:39.320 that turns over five days. They last about fifteen years. 0:21:39.560 --> 0:21:44.920 Yeah, it's such a like a beautiful, elegant system. Yeah, 0:21:44.920 --> 0:21:47.879 that we have right to keep us alive. Red blood 0:21:47.880 --> 0:21:50.880