WEBVTT - Genes 101 0:00:00.160 --> 0:00:07.400 Brought to you by Toyota. Let's go places. Welcome to 0:00:07.560 --> 0:00:14.079 Forward Thinking. Hey there, and welcome to Forward Thinking, the 0:00:14.120 --> 0:00:16.119 podcast that looks at the future and says, carry on 0:00:16.200 --> 0:00:19.079 my wayward son. I'm Jovin Strickland, I'm Lauren Bocubon, and 0:00:19.160 --> 0:00:21.599 I'm Joe McCormick. And we wanted to kind of talk 0:00:21.640 --> 0:00:25.520 about genes and genetics and d n A and chromosomes. 0:00:25.520 --> 0:00:28.720 And it's because we have this whole podcast where we're 0:00:28.760 --> 0:00:32.000 going to be talking about gene therapy coming up. But 0:00:32.600 --> 0:00:35.279 really to understand gene therapy, we kind of need to 0:00:35.520 --> 0:00:38.720 lay that foundation first, so a little bit. And yeah, 0:00:39.440 --> 0:00:41.640 so for those of you, those of you who who 0:00:41.720 --> 0:00:44.760 have been out of middle school science for quite some time, 0:00:44.840 --> 0:00:48.559 like me, might need a refresher course, or maybe you 0:00:48.720 --> 0:00:51.600 never really studied this. For those of you who have 0:00:52.400 --> 0:00:55.920 a significant grounding in this, either educationally or perhaps professionally, 0:00:56.760 --> 0:00:59.280 just humor us because we wanted to make sure that 0:00:59.360 --> 0:01:02.840 we define in some terms and understood things before we 0:01:02.920 --> 0:01:05.760 launched into a full gene therapy discussion. Come on, that 0:01:05.840 --> 0:01:08.080 makes it sound a little dry and sterile. We're we're 0:01:08.120 --> 0:01:11.840 about to talk about some really huge molecules. I mean, 0:01:11.880 --> 0:01:16.000 I mean big, big molecules, Yes, big enough where if 0:01:16.040 --> 0:01:18.040 they weren't so darn thin, you would be able to 0:01:18.080 --> 0:01:20.440 see them with the naked eye once they are unfurled, 0:01:20.920 --> 0:01:24.080 because DNA molecules could be a couple of centimeters long, 0:01:24.120 --> 0:01:29.560 depending upon what you harvested them from. Ye, but they're 0:01:29.640 --> 0:01:33.080 very very thin, so they wouldn't see them anyway. But 0:01:33.120 --> 0:01:37.600 they're quite long. Um. So, early days of modern biology, 0:01:38.000 --> 0:01:44.080 you had scientists looking at cells through microscopes, and uh, 0:01:44.400 --> 0:01:47.080 normally you wouldn't be able to see things like chromosomes 0:01:47.120 --> 0:01:51.840 within the nucleus of a cell except during cellular division, 0:01:52.240 --> 0:01:54.440 because at that point the chromosomes kind of get all 0:01:54.520 --> 0:01:57.200 compact and they get dark enough where you can see them. 0:01:57.720 --> 0:02:02.880 So that led people to think. Specifically, scientists think, huh, 0:02:03.040 --> 0:02:06.120 I wonder what that stuff is around around What part 0:02:06.120 --> 0:02:08.640 of the timeline was this did you, oh, gosh, this 0:02:08.639 --> 0:02:11.720 would be in the nineteen well, nineteen thirties and forties really, 0:02:11.760 --> 0:02:16.040 But if you want to talk about the actual evolution 0:02:17.880 --> 0:02:22.120 of of of genes and heredity and this sort of 0:02:22.160 --> 0:02:24.160 these sort of concepts, you actually have to go back 0:02:24.480 --> 0:02:28.160 quite some ways to the mid nineteenth century. Actually this 0:02:28.240 --> 0:02:30.160 is interesting and a lot of people don't even know this. 0:02:30.240 --> 0:02:35.200 Charles Darwin didn't know anything about jenes no, well maybe 0:02:35.480 --> 0:02:38.520 sort of as a concept like the idea of inherited traits, 0:02:38.560 --> 0:02:40.880 but didn't know anything about d n A. Right, he 0:02:40.919 --> 0:02:43.600 had this practical evidence that that he was being presented 0:02:43.639 --> 0:02:46.160 with and that he was thinking about really hard. But 0:02:46.160 --> 0:02:48.320 but they had no way of knowing what the discreet 0:02:48.480 --> 0:02:52.320 element of transferral of traits actually was. And in fact, 0:02:52.639 --> 0:02:56.160 there there were other people working on learning about, you know, 0:02:56.200 --> 0:02:59.080 how traits are passed down at the same time, at 0:02:59.120 --> 0:03:03.040 the same time, and they didn't. They didn't they didn't 0:03:03.080 --> 0:03:07.000 match up. In fact, the first one really Gregor Mendel, 0:03:07.360 --> 0:03:11.520 who was an Austrian monk, and uh he decided that 0:03:11.560 --> 0:03:15.200 he was going to investigate how traits were passed down 0:03:15.240 --> 0:03:19.520 by using hybridized p plants, and he wanted to just see, 0:03:19.919 --> 0:03:24.120 you know what determines how certain traits get passed down. 0:03:24.600 --> 0:03:28.760 And a lot of experiments in these early days would 0:03:28.840 --> 0:03:33.000 only last a few months, maybe a year, and so 0:03:33.080 --> 0:03:34.880 you would only have a certain number of generations of 0:03:34.920 --> 0:03:37.920 plants to work with. And the general thinking at that 0:03:37.960 --> 0:03:41.240 time was that you would get these unusual traits that 0:03:41.240 --> 0:03:43.760 would pop up in plants, but that the hybrids would 0:03:43.800 --> 0:03:47.760 eventually revert back to the original form of the plant 0:03:47.920 --> 0:03:50.480 several generations down the line, like like it would just 0:03:50.480 --> 0:03:53.000 be a little side step, but then it would re 0:03:53.120 --> 0:03:57.240 orient itself. That well, Gregor Mendel decided to kind of 0:03:57.280 --> 0:03:59.720 really look at this, and over the course of about 0:03:59.760 --> 0:04:05.200 eight years and thousands and thousands of plants, he discovered 0:04:05.240 --> 0:04:08.400 that there were some interesting things going on, that that 0:04:08.960 --> 0:04:11.960 there were different types of traits that were being passed on, 0:04:12.280 --> 0:04:14.720 and actually started to lay the groundwork for things like 0:04:15.080 --> 0:04:19.440 dominant traits versus recessive traits, things that you know, if 0:04:19.640 --> 0:04:22.440 if a p plant had once certain type of trait 0:04:22.839 --> 0:04:25.160 that was more likely to be passed down than other ones. 0:04:25.200 --> 0:04:28.200 And he really started to put all this together, but 0:04:29.120 --> 0:04:32.920 no one really gave it much thought, including including himself. 0:04:33.000 --> 0:04:35.440 He thought that this was an interesting thing, but didn't 0:04:35.720 --> 0:04:40.720 apply it to a wider range of life forms beyond 0:04:40.760 --> 0:04:44.039 pe plants. Well, he didn't know about DNA either. No, No, 0:04:44.120 --> 0:04:46.840 this is men daily in genetics. So again it's just 0:04:46.960 --> 0:04:51.960 based on um sort of phenotypical markers that show up 0:04:52.000 --> 0:04:55.040 things you can see with the naked eye parent physical traits. 0:04:55.120 --> 0:04:58.240 So he he did, he did figure out the or 0:04:58.279 --> 0:05:01.320 he did lay the groundwork for pre dominant traits versus 0:05:01.640 --> 0:05:04.800 recessive traits. And he also figured out that the traits 0:05:04.839 --> 0:05:09.320 were not necessarily dependent upon one another, right, they were independent. 0:05:09.560 --> 0:05:12.400 A lot of traits just had one set of traits 0:05:12.400 --> 0:05:14.720 and another set of traits didn't necessarily have to be 0:05:14.839 --> 0:05:19.720 present for the next generation to start to exhibit them. 0:05:19.760 --> 0:05:23.440 So that was also interesting. Uh. In eighteen sixty nine, 0:05:24.160 --> 0:05:27.720 that's when Friedrich Mischer, who was a German chemist, was 0:05:27.760 --> 0:05:32.200 the first person to isolate DNA from cell nuclei that's 0:05:32.400 --> 0:05:37.640 where you would find DNA generally speaking, And uh, he 0:05:38.120 --> 0:05:41.240 wasn't sure what the heck it was, this this sort 0:05:41.279 --> 0:05:45.400 of white, acidic substance, and no one was really sure 0:05:45.400 --> 0:05:48.120 if it even had a purpose. In fact, for for 0:05:48.279 --> 0:05:50.920 years they just sort of discounted it as just like 0:05:50.960 --> 0:05:53.320 this is just something that's in cells, but it doesn't 0:05:53.320 --> 0:05:59.440 do anything important, and uh, but it's understanding. There was 0:05:59.480 --> 0:06:02.799 no way from him to know really. Inties and forties, 0:06:02.839 --> 0:06:06.159 that's when you had scientists really looking at it and 0:06:06.640 --> 0:06:10.240 trying to figure out exactly what this stuff was. What 0:06:10.400 --> 0:06:13.160 was important about it. They began to learn that DNA 0:06:13.320 --> 0:06:16.680 was made up of a five sided sugar uh, and 0:06:16.800 --> 0:06:20.680 that it also had these base pairings of well, they 0:06:20.680 --> 0:06:22.120 didn't even know what it was pairings at the time. 0:06:22.120 --> 0:06:26.560 They knew that there were these other polynucleotides inside DNA, 0:06:27.080 --> 0:06:29.760 they didn't know the significance of it. And they also 0:06:29.839 --> 0:06:33.760 knew that DNA had a protein involved with it. The 0:06:33.760 --> 0:06:38.000 protein is the scaffolding that DNA wraps itself around, but 0:06:38.279 --> 0:06:41.159 they didn't they weren't sure what significance any of that was. 0:06:41.839 --> 0:06:43.800 To take get to about nineteen fifty, that's when a 0:06:43.880 --> 0:06:48.800 check scientist named Irvin Cargoff discovered the base composition of 0:06:48.880 --> 0:06:51.960 DNA and measured the amount of the four nucleotides you 0:06:51.960 --> 0:06:53.920 can find in DNA. And I'll cover that in a minute. 0:06:54.920 --> 0:06:58.279 And he also noticed that something interesting that you know, 0:06:58.320 --> 0:07:01.480 the four nucleotides, we generally call them A, T, C, 0:07:01.720 --> 0:07:04.960 and G for their names. And again I'll go through 0:07:05.000 --> 0:07:07.880 the names when I can get my tongue around them. 0:07:07.920 --> 0:07:10.640 Can I try? Can I try go for it? Okay, 0:07:10.680 --> 0:07:21.240 it's uh oh manin, thiamine, adeni ad and id ad 0:07:21.280 --> 0:07:28.559 anine and oh guanne Okay, so how close was I 0:07:28.600 --> 0:07:33.920 think I was messing up some idine thymine citazine gun 0:07:34.720 --> 0:07:37.720 And then if you're going with RNA, which of course 0:07:37.920 --> 0:07:41.440 is the other component we have to talk about eventually, Uh, 0:07:41.600 --> 0:07:44.000 arny doesn't have thymine, but it does have ur a 0:07:44.080 --> 0:07:47.960 cell and your cell ends up acting pairing, pairing with 0:07:48.000 --> 0:07:50.240 at an in the same way thyman does. So it's 0:07:50.280 --> 0:07:55.560 you don't have you're really uh, consult your physician. No, 0:07:56.440 --> 0:08:00.760 your cell it fulfills that same purpose because what happens 0:08:00.800 --> 0:08:04.760 is these these based nucleotides pair with one another. Now, 0:08:04.760 --> 0:08:06.880 at this point in nineteen fifty, they didn't know anything 0:08:06.880 --> 0:08:10.960 about pairing. What Chargov saw was that if you looked 0:08:10.960 --> 0:08:14.720 at the ending and the thyming nucleotides, they were roughly 0:08:14.760 --> 0:08:17.480 equivalent to each other. And the same was true for 0:08:17.520 --> 0:08:20.880 the site of zine and guani nucleotides. Those were equivalent 0:08:20.920 --> 0:08:25.480 to one another. And so this, uh, this gave rise 0:08:25.520 --> 0:08:28.680 to what is now known as Chargovs rules, which was 0:08:28.720 --> 0:08:31.040 just that if you find a certain amount of one, 0:08:31.120 --> 0:08:33.480 then you know that that's the same amount for the 0:08:33.640 --> 0:08:37.199 other one. And it also laid the groundwork for later 0:08:37.440 --> 0:08:40.880 scientists to kind of figure out about this nucleotide pairing 0:08:41.080 --> 0:08:44.760 that the reason why there are equal amounts is because 0:08:45.120 --> 0:08:47.679 they pair up in a strand of DNA. So that 0:08:47.760 --> 0:08:50.400 takes us up to that. Nineteen fifty two, that's when 0:08:50.400 --> 0:08:54.679 Alfred Hershey and Martha Chase really uh they got behind 0:08:54.679 --> 0:08:58.040 the idea that it was DNA that carried genetic information, 0:08:58.480 --> 0:09:02.480 that it carried this hereditary information, rather than the protein 0:09:02.640 --> 0:09:05.560 scaffolding that the DNA was wrapped around, because at the 0:09:05.600 --> 0:09:08.320 time no one was really sure and there were some 0:09:08.400 --> 0:09:11.240 people who were saying, it's the protein that carries the 0:09:11.240 --> 0:09:16.280 hereditary information, not the DNA molecule. And uh so they decided, 0:09:16.520 --> 0:09:18.680 should we sort that out? Now? Are we getting to that. 0:09:18.880 --> 0:09:21.320 We'll get to it. We'll get to never you fear 0:09:21.520 --> 0:09:26.720 trust in Jonathan, Yes, but but trust in specific instant. 0:09:26.760 --> 0:09:28.680 There's a lot of molecules in here, all right, all right, 0:09:28.720 --> 0:09:31.760 to be fair, all right, So the protein is the 0:09:31.800 --> 0:09:35.680 scaffolding that the DNA wraps itself around. Okay, so, and 0:09:35.800 --> 0:09:40.920 DNA itself at least is in the business of making proteins. Yes, yes, 0:09:41.160 --> 0:09:44.280 so it makes proteins. What technically, what does is really 0:09:44.280 --> 0:09:47.320 gives the instructions for amino acids. Which amino acids are 0:09:47.320 --> 0:09:51.200 the building blocks for proteins. But I'll get there, trust 0:09:51.320 --> 0:09:55.200 me anyway. So, uh, they weren't sure whether or not 0:09:55.280 --> 0:09:57.880 it was the protein element or the DNA element that 0:09:57.920 --> 0:10:02.960 actually passed down U hereditary information. And so they Hershey 0:10:03.040 --> 0:10:05.520 and Chase, who thought it was DNA, decided they would 0:10:05.559 --> 0:10:07.679 do an experiment, and so I think there was. They 0:10:07.720 --> 0:10:11.360 got some They got some DNA and they from a 0:10:11.440 --> 0:10:14.480 bacterial virus called T two. Actually, uh, it would raise 0:10:14.520 --> 0:10:18.280 its thumb as it was lowered into lava. Uh. The 0:10:18.400 --> 0:10:20.800 T two virus, Actually it has a shred of it's 0:10:20.880 --> 0:10:22.720 it's a virus that has a shred of DNA inside 0:10:22.800 --> 0:10:25.640 and a little tiny piece of protein inside it as well. 0:10:26.080 --> 0:10:29.199 So what Chase and her She did or hers Chase 0:10:29.240 --> 0:10:32.319 because it's usually called Hershey Chase experiment. They ended up 0:10:32.360 --> 0:10:36.680 inserting a radioactive tag in the DNA of this virus 0:10:36.720 --> 0:10:38.280 and then allowed the virus to go ahead and do 0:10:38.320 --> 0:10:40.560 its a little viral thing where it would go and 0:10:40.679 --> 0:10:43.319 replicate replicate itself. And then they noticed that all the 0:10:43.440 --> 0:10:46.480 viruses that were replicated also were radioactive. They had this 0:10:46.559 --> 0:10:51.200 radioactive tag. They repeated the experiment by tagging the protein 0:10:51.880 --> 0:10:54.880 with this radioactive tag and did the same thing and 0:10:54.920 --> 0:10:58.400 saw that the the next generation of viruses did not 0:10:58.760 --> 0:11:02.400 have the radioactive tag. Uh huh. They say, this shows 0:11:02.440 --> 0:11:05.239 that the DNA is what's passing down this hereditary information, 0:11:05.280 --> 0:11:09.000 not the protein. So bite me, although they said in 0:11:09.040 --> 0:11:13.040 a much nicer way scientific yes, that was probably whatever 0:11:13.080 --> 0:11:15.520 the latin is for biting me, right, it's it's pure viewed. 0:11:15.720 --> 0:11:19.719 So that brings us to nineteen fifty three, and this 0:11:19.800 --> 0:11:23.160 is when the probably the most famous of the discoveries, 0:11:23.360 --> 0:11:25.920 um you could argue for for the whole history of 0:11:26.000 --> 0:11:28.960 DNA and jeans it comes about. And that's when the 0:11:29.000 --> 0:11:34.199 actual molecular structure of DNA was discovered. The soul Watson, Crick, Franklin, 0:11:34.760 --> 0:11:38.160 and Wilkins. Yes, James Watson and Francis Crick are the 0:11:38.200 --> 0:11:41.680 one to who are normally credited. It's Watson and Crick. 0:11:41.720 --> 0:11:44.640 You always hear Watson and Crick, but they their work 0:11:44.720 --> 0:11:47.679 was made possible by the work of two other scientists, 0:11:48.160 --> 0:11:52.040 Rosalind Franklin and Maurice Wilkins, who all had been working 0:11:52.080 --> 0:11:55.800 on this And without the work of Wilkins and Uh 0:11:55.840 --> 0:12:00.160 and Franklin, you wouldn't have had the information Watson Krick 0:12:00.200 --> 0:12:02.720 wouldn't have had the information they needed to learn the 0:12:02.760 --> 0:12:05.920 actual structure of DNA. UH. Franklin had been using X 0:12:06.000 --> 0:12:08.800 ray diffraction to observe living cells and it was that 0:12:08.800 --> 0:12:11.640 that gave them the ability to take a look at, uh, 0:12:11.720 --> 0:12:17.000 this double helix structure that DNA has, and they could 0:12:17.240 --> 0:12:19.960 tell that it was this double helix structure that would 0:12:19.960 --> 0:12:24.719 pull apart to make copies of itself during cellular division. UH. 0:12:24.760 --> 0:12:27.440 And then if you wanna, you know, the next big, big, 0:12:27.480 --> 0:12:31.160 big moment in genes, which will talk about more in 0:12:31.200 --> 0:12:33.680 another episode, it was the ninety seven which was the 0:12:33.679 --> 0:12:36.840 first sequencing of a complete genome, which was the bacteria 0:12:36.920 --> 0:12:41.640 fage f x one seven four. So, um, now we're 0:12:41.640 --> 0:12:43.640 going to talk a little bit about what these structures 0:12:43.679 --> 0:12:46.440 actually are and what you know, the define some more 0:12:46.600 --> 0:12:49.040 terms because there's a lot of confusion when it comes 0:12:49.080 --> 0:12:52.840 to DNA, genes, genome, chromosomes, and just kind of use 0:12:52.880 --> 0:12:55.839 them interchangeably, right, and and you know it helps to 0:12:55.960 --> 0:12:59.600 get get a little more precise. Okay, Well, one clear 0:12:59.640 --> 0:13:03.360 distinct shinn' make I think is that gene is sort 0:13:03.400 --> 0:13:07.439 of a classification where that we have whereas d N 0:13:07.520 --> 0:13:12.320 A as a molecule UM and what so the structure 0:13:12.360 --> 0:13:14.600 of DNA, we could talk about that for a little. Sure, 0:13:14.679 --> 0:13:16.480 it's like it's like you said, it's a double helix, 0:13:16.480 --> 0:13:20.920 so you'd have to imagine kind of a twisted ladder. 0:13:22.200 --> 0:13:23.959 Take a ladder and twist in a right handed or 0:13:24.000 --> 0:13:27.400 clockwise direction, and so correct me if I'm wrong. But 0:13:27.440 --> 0:13:30.079 I think I just I just realized for the first 0:13:30.080 --> 0:13:32.760 time that what the ladder is actually built of is 0:13:32.800 --> 0:13:36.920 that the sides of the ladder are basically just sugar molecules, 0:13:37.360 --> 0:13:40.800 and it's the wrongs of the ladder that contain the 0:13:40.880 --> 0:13:46.440 crucial genetic information. Those are the that's the nucleotide pairings. Yeah, so, yeah, 0:13:46.480 --> 0:13:48.880 you've got the and. And the reason why the nucleotide 0:13:48.920 --> 0:13:52.719 pairings have to be A and T and C and 0:13:52.800 --> 0:13:55.680 G is that if you tried to put up any 0:13:55.679 --> 0:13:58.640 other type of pairing, the wrongs would be the wrong 0:13:58.640 --> 0:14:02.280 width and you wouldn't have of a a stable structure anymore. 0:14:02.720 --> 0:14:05.640 The only way the wrungs are of the correct width 0:14:05.679 --> 0:14:08.559 so that this double helix structure can remain stable and 0:14:08.880 --> 0:14:11.520 remain intact is to have it paired up the way 0:14:11.559 --> 0:14:15.480 I said a t n C. And it's the only way. Uh. 0:14:15.800 --> 0:14:19.600 DNA of course stands for de oxyde de oxy ribonucleic acid. 0:14:19.640 --> 0:14:21.000 I knew I was going to mess that up before 0:14:21.040 --> 0:14:25.480 I could get through it once. But deoxy acid. Yeah, 0:14:25.640 --> 0:14:28.480 you know, you just had the benefit of hearing me 0:14:28.520 --> 0:14:34.800 say it twice. Mr Adenine thyming that one. So they 0:14:35.800 --> 0:14:39.880 the acid here has this, Uh, the base pairings they 0:14:40.000 --> 0:14:45.040 bond with hydrogen bonds the four nucleotides, right, And it's 0:14:45.080 --> 0:14:49.680 the sequence of bonds, the sequence of pairings that create 0:14:49.800 --> 0:14:56.160 genetic information. Uh. Not all of DNA is encoded genetic information. 0:14:56.240 --> 0:14:58.320 Some of it is behaving in a way that we 0:14:58.360 --> 0:15:01.680 don't fully understand yet. It's sometimes it's called junk DNA. 0:15:02.440 --> 0:15:05.680 Sometimes it's called non coded DNA. At any rate, it 0:15:05.760 --> 0:15:09.200 almost seems like it's, you know, gibberish. That's just there 0:15:09.240 --> 0:15:11.720 to break up the genetic coding. Now, when I say 0:15:11.760 --> 0:15:13.960 just there to break up, that's what I'm saying from 0:15:13.960 --> 0:15:17.120 a from an uninformed perspective, that's what it looks like. 0:15:17.160 --> 0:15:19.040 But we may learn in the future that it has 0:15:19.040 --> 0:15:24.560 a very specific purpose that we just don't know about yet. Right, Okay, Well, 0:15:24.600 --> 0:15:27.040 I think we don't hear the term junk DNA is 0:15:27.080 --> 0:15:31.120 often these we just don't know what, so we often 0:15:31.160 --> 0:15:33.800 call it noncoding because we we don't recognize it as 0:15:33.840 --> 0:15:38.560 coding for specific type of protein. So one, what what 0:15:38.640 --> 0:15:41.760 makes DNA so special is a molecule. What makes it 0:15:41.800 --> 0:15:44.160 not like any other molecule. There's a lot of things 0:15:44.160 --> 0:15:46.200 that make it not like any other molecule. For the fact, 0:15:46.320 --> 0:15:49.560 one thing is that this the sequence of bonds, can 0:15:49.600 --> 0:15:54.480 actually pass on actual information. These instructions for creating amino acids, 0:15:54.480 --> 0:15:57.040 which in turn create proteins, and the proteins are pretty 0:15:57.120 --> 0:15:59.800 much what tell your cells what to do and when 0:16:00.080 --> 0:16:02.600 they're what makes your body go. It's it's right, it's 0:16:02.640 --> 0:16:05.000 it's it's what makes you grow. What makes your your 0:16:05.480 --> 0:16:07.640 you know, body parts develop into the body parts that 0:16:07.680 --> 0:16:11.200 they are, rather than makes you be you is when 0:16:11.240 --> 0:16:14.960 it really comes down, it's the size of your brain pan. 0:16:15.480 --> 0:16:18.840 It's also the DNA is in most of our cellular nuclei, 0:16:19.360 --> 0:16:22.720 and so essentially the entire record of what makes you 0:16:22.720 --> 0:16:26.960 you is in every single nuclei of these cells. Did 0:16:27.000 --> 0:16:30.880 you know, though, that the nuclear nuclei aren't the only 0:16:30.960 --> 0:16:35.240 part of your cells that have DNA shut your mouth, Yeah, yeah, 0:16:35.320 --> 0:16:37.080 that's right, which you get from your mom and not 0:16:37.160 --> 0:16:39.960 from your dad at all. Really. Yeah, So you get 0:16:40.000 --> 0:16:44.080 your nucleic DNA that that comes from your mom and 0:16:44.160 --> 0:16:46.200 your dad, and that's in the nucleus of your cells 0:16:46.200 --> 0:16:48.440 and tells tells the rest of your body how to 0:16:48.480 --> 0:16:51.120 make itself and what to do. That comes from both parents, 0:16:51.160 --> 0:16:54.400 but just from your mom. You get mitochondrial DNA, and 0:16:54.440 --> 0:16:57.280 that's a separate little bit of DNA that lives in 0:16:57.320 --> 0:16:59.840 the mitochondria and the cells, and the mitochondria of a 0:17:00.000 --> 0:17:03.120 all is sort of like the power plant. Sure, yeah, yeah, exactly, 0:17:03.160 --> 0:17:05.600 And when you talk about genes, you're really talking about 0:17:05.600 --> 0:17:09.280 a specific strip of DNA. It's sort of a think 0:17:09.280 --> 0:17:12.439 of it like magnetic tape. For for if you're a 0:17:12.480 --> 0:17:16.000 computer storage kind of person. So this would be a 0:17:16.160 --> 0:17:19.359 length of magnetic tape upon which there are instructions, and 0:17:19.400 --> 0:17:22.359 then there would be noise between the instructions and the 0:17:22.400 --> 0:17:25.760 next set of instructions, which are for something totally different, right, 0:17:25.880 --> 0:17:28.800 some other some other process. Now, in this case, the 0:17:28.840 --> 0:17:31.960 process we're talking about, it's usually to create proteins through 0:17:32.440 --> 0:17:36.320 the production of amino acids UM. Now the other thing 0:17:36.359 --> 0:17:39.000 you can the other thing that's really important to remember 0:17:39.240 --> 0:17:42.919 that genes are like the fundamental unit of heredity. Okay, 0:17:42.960 --> 0:17:44.520 so that's sort of like you can think of a 0:17:44.560 --> 0:17:48.840 gene as the equivalent of an atom, but only when 0:17:48.880 --> 0:17:51.439 we're talking in terms of of heredity. So this is 0:17:51.920 --> 0:17:56.959 as small as it gets. Uh. The relationship between genes 0:17:57.000 --> 0:18:00.920 and traits is very complex. Uh. There our genes that 0:18:01.000 --> 0:18:05.880 can manifest in several different traits. Uh, and then there 0:18:05.880 --> 0:18:09.360 are some traits that require multiple genes to manifest, so 0:18:09.760 --> 0:18:12.760 it's not a one to one relationship at all. Right. 0:18:13.520 --> 0:18:16.480 One thing you can think of making a gene discrete 0:18:16.520 --> 0:18:18.679 is that a gene is sort of a section of 0:18:18.760 --> 0:18:23.040 information that can have different what are called alleles, and 0:18:23.080 --> 0:18:26.600 so that's a different variation on that set of information. 0:18:26.960 --> 0:18:30.560 And in a gene pool, there will be multiple alleles. 0:18:30.560 --> 0:18:33.040 So you can have one gene and then a different 0:18:33.119 --> 0:18:35.680 version of that gene, different version of that gene found 0:18:35.720 --> 0:18:38.679 in different individuals. All right. So a human gene is 0:18:38.720 --> 0:18:42.840 typically between twenty seven thousand and two million base pairs. Okay, 0:18:42.840 --> 0:18:45.840 so those nucleo tide pairings, that's how many are in 0:18:45.880 --> 0:18:48.400 a typical gene. Between twenty seven thousand, two million, which 0:18:48.400 --> 0:18:51.119 is a huge range. And it's also interesting to know 0:18:51.320 --> 0:18:54.720 that a thousand base pairs would technically be enough to 0:18:55.200 --> 0:18:58.960 encode most proteins. And that's what these genes are doing 0:18:59.000 --> 0:19:03.320 there for the most part, they're meant to encode proteins. Uh. 0:19:03.359 --> 0:19:08.080 And so it's interesting to think that the typical genes 0:19:08.119 --> 0:19:11.400 and the human seem to be really inefficient. And that's 0:19:11.400 --> 0:19:13.360 because there are large parts of genes that are not 0:19:13.520 --> 0:19:17.600 meant to encode, and they're they're also really complicated. Most 0:19:17.600 --> 0:19:19.480 of them make more than one protein the average is 0:19:19.600 --> 0:19:23.200 three actually, right and um and and they are not 0:19:24.000 --> 0:19:26.760 they're not really discrete units. They interact with each other 0:19:26.840 --> 0:19:29.920 in interesting ways, right and so so here's how they 0:19:29.960 --> 0:19:33.919 actually work. So cells make a copy of the gene 0:19:34.320 --> 0:19:36.840 through you know, they take the length of DNA where 0:19:36.880 --> 0:19:41.919 the genetic information is relevant. This whole process is called transcription. 0:19:42.680 --> 0:19:44.600 That copy ends up moving to another part of the 0:19:44.640 --> 0:19:46.520 cell where it's used to create a chain of protein 0:19:46.560 --> 0:19:51.960 subunits amino acids. That parts called translations. So transcription uses RNA, 0:19:52.440 --> 0:19:55.760 that's the copy that is created out of this RNA 0:19:55.920 --> 0:19:59.680 is made up of ribonucleotides, and so those bases U 0:20:00.040 --> 0:20:02.320 compliment the ones in DNA. But like we said earlier, 0:20:02.640 --> 0:20:05.960 there's no thymine, so they uses eurusil instead, which you 0:20:06.119 --> 0:20:10.879 and A buying together. So there's no real problem there. Uh. Now, 0:20:11.040 --> 0:20:15.520 the genes have protein coding sections called xns and non 0:20:15.600 --> 0:20:19.280 coding segments called in tron's. So the RNA section RNA 0:20:19.400 --> 0:20:23.280 sections that correspond to in trons, the non coding parts. 0:20:23.480 --> 0:20:26.480 Those parts get generally they get removed from the RNA. 0:20:26.640 --> 0:20:29.480 It's called splicing. It splices out. It's kind of just 0:20:29.520 --> 0:20:31.639 like you know you're splicing film. You take out the 0:20:31.640 --> 0:20:33.480 part you don't want, and then you merge the other 0:20:33.520 --> 0:20:35.879 two pieces together. So that way you just have the 0:20:35.880 --> 0:20:39.760 coding parts left, the xns in other words, and that 0:20:39.800 --> 0:20:43.840 becomes what is known as messenger RNA. Well, then you've 0:20:43.880 --> 0:20:49.600 got these other bits of RNA, uh, the the the 0:20:49.640 --> 0:20:53.040 transfer ribonucleic acid or t RNA. So you've got your 0:20:53.040 --> 0:20:57.960 messenger RNA, you got your transfer ribonucleic acid. Uh. You 0:20:58.000 --> 0:21:00.120 get the two of them together, and it's like a 0:21:00.160 --> 0:21:05.160 spaceship docking with a space station. So you look at 0:21:05.160 --> 0:21:08.639 these three base pair will not even base pair uh 0:21:08.880 --> 0:21:13.440 three exxons. So you code this by the three letters 0:21:13.480 --> 0:21:15.679 that they might be like g G G or it 0:21:15.720 --> 0:21:19.600 could be g U A or so anyway, you you 0:21:19.640 --> 0:21:24.520 get those those three codes, the appropriate t RNA will 0:21:24.680 --> 0:21:26.800 doc with that, and that gives the t RNA the 0:21:26.920 --> 0:21:31.000 instruction to make the amino acid whatever it's supposed to 0:21:31.080 --> 0:21:34.280 be according to the messenger RNA. So the messenger RNA 0:21:34.480 --> 0:21:37.600 is essentially the recipe. The t RNA all will only 0:21:37.640 --> 0:21:40.320 produce one specific amino acid, and it only will work 0:21:40.359 --> 0:21:42.600 if they can doc with that part of the m RNA. 0:21:43.359 --> 0:21:46.840 It'll build a protein based on all these amino acid chains. 0:21:47.640 --> 0:21:50.480 And uh, and that's the basis there. So you've got 0:21:50.480 --> 0:21:54.160 your amino acids and proteins. That gives the instructions for 0:21:54.240 --> 0:21:57.400 everything else that's going on. Really and uh, there's your 0:21:57.440 --> 0:22:01.080 there's your basic genes and how those genes work and 0:22:01.080 --> 0:22:05.840 how they replicate proteins. Now, let's talk about chromosomes. So 0:22:05.880 --> 0:22:09.080 we've we've got DNA. That's the molecule. We've got the genes. 0:22:09.119 --> 0:22:12.240 That's lengths on the molecule that give instructions for things 0:22:12.320 --> 0:22:19.040 like protein generation. Chromosomes are essentially packages of genes, all right, 0:22:19.200 --> 0:22:23.760 so life forms have chromosomes, they don't all have the 0:22:23.840 --> 0:22:27.840 same types of chromosomes or the same number of chromosomes. Uh. 0:22:28.080 --> 0:22:30.639 Humans have twenty three pairs of chromosomes, one pair of 0:22:30.680 --> 0:22:35.199 that sex chromosomes. So uh, that's different if you're female 0:22:35.280 --> 0:22:38.880 or male. Obviously for females too, X chromosomes. If you're male, 0:22:38.880 --> 0:22:43.199 it's an X and Y chromosome. Why because we like you. 0:22:43.440 --> 0:22:49.320 And then the rest of the chromosomes are all other types, right, 0:22:49.359 --> 0:22:52.639 And you've got these are the ones that uh, you 0:22:52.760 --> 0:22:56.119 have one pair you have inherited from your father, and 0:22:56.160 --> 0:22:58.840 one pair you've inherited from your one half of the 0:22:58.840 --> 0:23:02.080 pair I should say you've inherited from your mother. And 0:23:02.160 --> 0:23:06.679 so you've got these packages of genes. They are of 0:23:06.720 --> 0:23:10.720 different sizes. Uh, they have different types of genes in them. 0:23:11.200 --> 0:23:16.720 Things that would be important for very related elements in 0:23:16.760 --> 0:23:21.000 our lives, like things that might be uh important instructions 0:23:21.040 --> 0:23:23.879 for the production of one type of cell that's very 0:23:23.920 --> 0:23:26.119 similar to another type of cell could be found in 0:23:26.160 --> 0:23:29.320 totally different chromosomes. So it's not like, you know, it's 0:23:29.320 --> 0:23:31.760 not like you would go to a library and pick 0:23:31.800 --> 0:23:34.480 out a book and like everything. There's no decimal system 0:23:34.640 --> 0:23:37.520 new it's kind of all jumbled up, but it makes 0:23:37.560 --> 0:23:41.240 sense to biology it were, or sense in the sense 0:23:41.280 --> 0:23:45.160