| 00:10 | All right. You guys let's get started. Hopefully we'll get done before |
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| 00:15 | rain. I don't know if it's rain. It just looks like dark |
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| 00:18 | out there. It is a little . That's gonna change will be hot |
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| 00:25 | , Right? Um So just to off today, what we're going to |
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| 00:28 | ? Just brief P. S. . On on selecting a topic for |
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| 00:32 | paper that's coming up. Remember the for selecting a topic is on |
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| 00:36 | Uh And then what we're gonna do we're going to uh kind of wrap |
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| 00:40 | with the signaling molecules if we need because I remember I stopped someplace, |
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| 00:45 | I might have just like blah blah blah blah blah blah at the |
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| 00:48 | So, you may need to kind do a little bit of that. |
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| 00:50 | what we're gonna do um is we're jump in and start dealing with membrane |
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| 00:55 | and how action potentials work. I've got a hand up question. |
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| 01:01 | . Like Well, so All so, that's a good question. |
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| 01:06 | a fair question. So, on there are how many groups? I |
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| 01:10 | it every year? So like roughly? Nine. There might not |
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| 01:15 | all nine available at this point because the group fills up it disappears and |
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| 01:19 | can't see it. Alright. But , that's how you select your |
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| 01:21 | So, what I do is I through and I look to see that |
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| 01:25 | has that and that's where your grade from for the like the point 05 |
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| 01:30 | or whatever it is that it's All right. So the key thing |
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| 01:33 | that I want you to get is you know it used to be that |
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| 01:37 | would allow students to actually change topics later in the semester. Like I |
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| 01:41 | had a student change the topic before second paper was do you know I |
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| 01:45 | ? It was just like dude you're yourself and they wanted to. So |
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| 01:49 | know, I let them and they did miserable. So um So we |
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| 01:52 | do that anymore instead. What we do is you should be thinking ahead |
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| 01:57 | what you want to do. But is the key thing right? Here |
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| 02:00 | something you're actually interested in. You if your first choice isn't available, |
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| 02:04 | your second choice. If your second then your third, your fourth, |
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| 02:07 | fifth. You work all the way the list. Don't just pick something |
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| 02:10 | it sounds sexy. All right. mean because that can lead to a |
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| 02:15 | of problems, right? If you're interested in what you're working on, |
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| 02:19 | not gonna wanna work on. If don't want to work on it, |
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| 02:21 | not gonna do it. If you do it, you get bad |
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| 02:23 | you get bad grades, You fail of school, You fail at |
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| 02:25 | you go live under a bridge. it's just it's like giving a mouse |
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| 02:29 | cookie. Some of you guys know one. Alright. Alright. |
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| 02:34 | so you know that's the idea and of it is if you start looking |
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| 02:37 | something, you pick up, let's you pick something and you start reading |
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| 02:40 | it and it's like uh I don't this. That's okay. Pick another |
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| 02:43 | . Just tell me to drop you of the group that you're not |
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| 02:45 | I'm not gonna be mad at you you pick two groups right now. |
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| 02:48 | mean you should only pick one. if you change your mind, you |
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| 02:52 | remove yourself. I have to remove . So just let me know and |
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| 02:54 | just click the button and out you . All right? But make sure |
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| 02:57 | already in another group before I click out of a group because you'd hate |
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| 03:00 | lose your spot and find out the you're interested disappears and then you're |
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| 03:04 | you get the picture. Alright. . Uh In regards to the |
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| 03:08 | sources remember are due next friday. what do you have next Tuesday |
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| 03:14 | Oh my goodness. It's a test . Do we have to have |
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| 03:18 | Alright. Anyway, so you have that really the whole purpose here is |
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| 03:22 | get you to start thinking about your as you picked your topic. You |
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| 03:26 | have gone through a couple of papers starting to review through them. You're |
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| 03:30 | to understand a little bit about what's on and each of these start serving |
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| 03:35 | the foundation on what you're gonna build paper on All right. And if |
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| 03:39 | never written a scientific paper before. you haven't taken genetics 33 or whatever |
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| 03:44 | genetics lab, you have done 33 . You haven't learned how to write |
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| 03:47 | . Let me just point out a of things real quick. There's what |
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| 03:50 | refer to as good resources and what refer to as bad and just stupid |
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| 03:55 | have here ugly. All right. you haven't seen the movie, you've |
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| 03:58 | to go see the movie. Not the test. Wait till after the |
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| 04:01 | . Alright. But anyway, good things. This is the scientific |
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| 04:04 | . So, what we're looking at is the primary literature things where they |
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| 04:08 | do the research. If someone tells that cigarette smoke causes cancer, how |
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| 04:12 | you know that they're telling you the ? You have to look at. |
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| 04:18 | I mean, even if it's a it's a review article, how do |
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| 04:20 | know it's real because somebody interpreted So you don't know if they interpreted |
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| 04:26 | a little later on next next I'm gonna show you some data that |
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| 04:30 | been wrong for about oh, I know 80 years because someone misunderstood the |
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| 04:37 | paper and it's been worked its way physiology forever. You know, and |
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| 04:42 | get to reproduction. I'm gonna show another one. That's a that's a |
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| 04:45 | . So part of this is looking the the original literature and interpreting and |
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| 04:49 | do I understand And do I agree what's being interpreted or being said in |
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| 04:55 | paper? So that's what a really . So the primary literature is what |
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| 04:59 | going to use for your discussions. is where you get your data. |
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| 05:02 | the fact that you're talking about the literature is probably where you're going to |
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| 05:07 | that a little bit. Let me me explain. Alright look I understand |
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| 05:10 | guys are juniors not writing an actual article. Right? But what you |
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| 05:15 | with the secondary literature is it helps you to the primary literature. So |
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| 05:19 | say you read a review article that you that smoking causes cancer and then |
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| 05:23 | see the reference point you're like okay I think that's true. Then I |
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| 05:26 | and look up the original paper and said yeah I can see here where |
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| 05:29 | got that data. And so now can refer to the primary even though |
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| 05:33 | started in the secondary you see how did that. That's perfectly legal. |
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| 05:39 | anyway, so this stuff, the literature is where you start moving into |
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| 05:43 | introduction or talking about the background So if you're making broad claims like |
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| 05:49 | know just oh I don't know t are responsible for X, Y and |
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| 05:54 | . Right. Well where did you that from? Well you probably got |
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| 05:57 | from the secondary literature right? It's factory that's generally well known or generally |
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| 06:03 | in the field of immunology. And that's where secondary literature is helpful. |
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| 06:07 | that are bad. Don't use your even though this is a great |
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| 06:10 | it's still about 10, 15 years of date. Um so there might |
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| 06:15 | more new, newer, more nuanced . Wikipedia is actually really good for |
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| 06:20 | you find definitions of things, Especially in the sciences. I use |
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| 06:24 | all the time like, you right before the lecture on the |
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| 06:27 | I have to look up single lipids single time because I always forget structurally |
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| 06:31 | it looks like. So I have go look it up. So Wikipedia |
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| 06:33 | great, you know, but it's a good resource for writing a paper |
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| 06:39 | you've probably learned at some point. on the internet is usually lies and |
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| 06:44 | of lies. So internet textbooks fall that same category. And then these |
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| 06:49 | the absolutely useless stuff. If you across a blog, somebody's opinion, |
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| 06:54 | that has a dot com at the of their page. Web page, |
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| 06:56 | usually a company that's trying to make so you can trust them. And |
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| 07:01 | of course, I'm just gonna slam magazines. If we have any journalism |
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| 07:06 | here, I'm sorry. They are dregs of science stuff. I'm just |
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| 07:13 | with that because they don't understand what writing about. So they interpret things |
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| 07:17 | inappropriately or incorrectly. And so very you will see that the stuff they're |
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| 07:22 | about is absolutely wrong. So just away from that stuff. This is |
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| 07:26 | you want to spend most of your , if not all your time. |
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| 07:34 | , you have a link to a . What's your library? Library dot |
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| 07:41 | dot e D U right, You , you know pop man, you |
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| 07:46 | know pub med. Right, so google pub med, N C B |
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| 07:50 | dot nlm dot something dot gov I remember there's something in there that I'm |
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| 07:56 | but those are your that's your two where you want to go really. |
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| 07:59 | med is probably the number one and you've downloaded the Zoo Otero as I |
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| 08:04 | , you should go download that that in for your your browser. It's |
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| 08:09 | I found a source click. I a source click. I found a |
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| 08:12 | click. Ok, put all my in the proper order like a |
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| 08:17 | There you go. Easy peasy. squeezy. There we go. |
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| 08:25 | Like I said, no tarot is you're gonna go like I cannot believe |
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| 08:28 | got my entire college career without knowing Otero is. So where you find |
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| 08:33 | information? Here you go. Ah it is. There's pub med. |
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| 08:36 | I left at the NIH so there's med. Uh web of knowledge is |
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| 08:42 | search engine is science search engine, scholars. Another one you can |
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| 08:46 | I just don't find google scholar quite helpful but since you guys are the |
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| 08:49 | generation and they already know everything You go ahead and use them |
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| 08:53 | Um But the library, this is you can actually get access to |
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| 08:57 | If you're on campus and you access library you can download directly is not |
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| 09:01 | problem. You don't have to do . But if you're off campus, |
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| 09:03 | think you usually have to log into university be a cougar net to get |
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| 09:07 | . And that's just because they're they're your I. P. Your your |
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| 09:12 | address to see where you are. So we have a lot of journals |
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| 09:16 | you can access through that. And you're really really bored and want to |
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| 09:18 | pay for park, you can go to the medical center and go use |
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| 09:21 | text medical center. Library parking is expensive. All right. So |
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| 09:30 | and everything at this point is now e journal there. It's all digital |
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| 09:33 | when I started when I made this , you could still actually go down |
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| 09:36 | and ask for the paper copy. Also if you don't know what you're |
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| 09:41 | , if you've never done this guess what? Librarians are really really |
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| 09:44 | at answering questions about how to use the materials at the library. |
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| 09:50 | And also they're very sexy. So be afraid to ask them. So |
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| 09:53 | this is what the female library, is what the male libraries look |
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| 09:56 | If you don't believe me, go the library and find out if I'm |
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| 10:02 | just saying. Alright. But anyway also you you know when you're in |
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| 10:06 | group, I think the group discussion is still open if you guys want |
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| 10:09 | talk to each other. I've never the groups to actually talk to each |
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| 10:12 | . But if you're like that chatty that has questions and you want to |
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| 10:16 | of talk to your group mates, can't the point here. That's not |
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| 10:19 | . That's the idea here is just , hey man, I'm lost. |
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| 10:22 | you help me? That might be a good way to actually get a |
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| 10:25 | bit of help if they help Great. If not, sorry. |
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| 10:28 | You can also talk to me. I can clarify stuff for you, |
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| 10:33 | I'm not gonna do your work. for example, like I've looked like |
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| 10:36 | can't find this. I'm like, have you used this search term, |
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| 10:38 | search term, that search terms and forth. I can point you in |
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| 10:41 | right direction. That sort of All right. So anyway, any |
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| 10:48 | about the first two assignments. First easy, pick a topic. Next |
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| 10:52 | . You can wait till after the and I think you just need a |
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| 10:55 | of 10 to start off with. and they're not permanent. I mean |
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| 10:59 | may go through your 10. You , you you look through it and |
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| 11:02 | like you start writing and stuff, might realize that seven of them are |
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| 11:05 | useless, thrown away. You the idea is is find your |
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| 11:08 | but you can't start research a research without a little bit of research. |
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| 11:14 | that's what this is. Is like you even made the attempt to go |
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| 11:17 | something? That's that's what this All right. Yeah. After Thursday's |
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| 11:27 | literally at 2:30, is that when got 30-30 is when when we get |
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| 11:32 | . So that's what it posts. questions about the paper 1st? I'm |
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| 11:39 | taunting you. I just I know know where your brains are. Test |
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| 11:43 | . Must know everything. Alright. know I didn't go into a lot |
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| 11:47 | detail here. Are there questions about slide before? I just skip over |
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| 11:50 | . I mean we're just talking about differences. There's tropic hormones, tropic |
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| 11:55 | , not tropic. Don't think umbrellas a little umbrella. Little Bella |
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| 11:59 | Tropic hormone is a hormone that regulates else. We distinguish them from the |
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| 12:03 | hormones because releasing hormones are up in hypothalamus, tropic hormones are also regulatory |
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| 12:09 | . They're just called tropic because of . That's prolactin. Eventually you learn |
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| 12:14 | the abbreviation on the test. I give you abbreviations. I will put |
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| 12:18 | full name and the abbreviation. So don't have to think that hard. |
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| 12:23 | at part. Um so what I to show here is the feedback |
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| 12:29 | Um uh I think we we cover really, really quickly. Did we |
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| 12:34 | those quickly that you want to go it again? Cause I can read |
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| 12:37 | slide just as you can. so prolactin? Think milk production that's |
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| 12:42 | than milk release. Which one is release? Oxytocin? That's the |
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| 12:48 | Alright, so oxytocin from the posterior is milk production. Alright. FSH |
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| 12:55 | LH follicle stimulating hormone. Don't think follicles, it's an ovarian follicle, |
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| 13:01 | where it gets its name from. know you don't know what that |
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| 13:03 | If you want to go to flip the back of the book, they'll |
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| 13:05 | a picture of it. You'll still not understand entirely. That's okay. |
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| 13:09 | lutin. Izing hormones which is really because what's a Luton and why am |
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| 13:13 | ? Isan? Isan ng it, , lutin. Izing Luton Luton comes |
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| 13:17 | lutein um which means yellowing and so a structure in the ovary after ovulation |
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| 13:25 | forms, it's it's basically called corpus literally means yellow or mustard yellow |
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| 13:33 | Right? I'm gonna say it but I'll just name things for what |
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| 13:36 | do or for what they look So big yellow body and it's a |
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| 13:40 | yellow body but the hormones that play role in these two things. That's |
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| 13:44 | they get their names from. They the hormones of the gonads are not |
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| 13:48 | to females. Males also use both hormones, they use them in different |
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| 13:52 | but that's where they got their names is from what was going on in |
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| 13:55 | ovary thyroid stimulating hormone. I have idea where that name comes from, |
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| 14:02 | the thyroid question. No, Okay. Um Adrenal cortical tropic |
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| 14:07 | It's just lots of syllables. Adrenal from adrenal cortex. Tropic regulates the |
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| 14:14 | cortex. So this plays a role the creation of the hormones of the |
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| 14:18 | cortex. Lastly, growth hormone or statin plays a role in metabolism and |
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| 14:25 | . So these are actually regulating downstream called the Samata meetings, which we |
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| 14:30 | get to later on in the But they that's where their tropic is |
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| 14:35 | they're not acting to cause growth They activate other molecules that play a |
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| 14:39 | in metabolism that lead to growth. is just a big chart to kind |
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| 14:43 | break it down for you. Do need to memorize it, but if |
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| 14:47 | get lost, it's like, um these are my hormones that I |
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| 14:51 | to know um what regulates them. pretty straightforward there either releasing hormones or |
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| 14:57 | the case of two of them, remember the two prolactin and growth |
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| 15:04 | Sorry, that's okay. It's all . Did I test you today? |
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| 15:07 | . So it's okay. Right. have both the gas and brake |
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| 15:11 | All right, The rest of them just all gas pedals that you take |
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| 15:14 | foot off to take your foot And I'm gonna show you this regulation |
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| 15:17 | on the next slide. Alright, you can see it here, there's |
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| 15:20 | hormone releasing hormone um down nope nope nope. It's not showing the |
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| 15:25 | H. I. H. Um there's something called G. H. |
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| 15:28 | . H. Which is growth hormone hormone which is the brake pedal. |
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| 15:34 | , prolactin has kind of the same . This is what I wanted to |
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| 15:40 | to. I know that I didn't it on Tuesday and looking at something |
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| 15:44 | this, it can seem like this really, really complex, complex, |
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| 15:48 | it's not all right. So in body there's simple feedback loops where you |
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| 15:53 | some sort of sensor that cause the of a signaling molecule that acts on |
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| 15:57 | target which causes something to happen. right. And then that's something that |
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| 16:01 | , serves as a feedback directly on sensor. All right, That's a |
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| 16:06 | simple model. But when we're talking the endocrine system and particularly about the |
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| 16:10 | pituitary, we take this simple model we expanded outward. Alright, so |
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| 16:15 | think of the three levels we have hypothalamus, the anterior pituitary and some |
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| 16:20 | of target tissue. This case that happens to be the adrenal cortex. |
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| 16:25 | , so what we're gonna do is hypothalamus releases a releasing hormone releasing hormone |
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| 16:29 | on the anterior pituitary to release the hormone the tropic hormone acts on the |
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| 16:33 | to release the hormone of interest. , so in our little model cortical |
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| 16:38 | releasing hormone, adrenal cortex, adrenal tropic hormone and cortisol. Alright. |
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| 16:44 | then does stuff. What do you know cortisol? Does anyone know |
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| 16:49 | Oh yeah. Bring it right because what life is right now. |
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| 16:54 | Just constant stress. Right? So the cortisol does the stuff. But |
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| 16:59 | do I know when to stop releasing cortisol when the stress goes away? |
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| 17:03 | write stress never goes away. It's there. It's when I have too |
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| 17:07 | cortisol in the blood. Right? what cortisol does it acts back on |
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| 17:11 | system on the tissue that is causing release of that tropic hormone and says |
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| 17:18 | stop being released. There's plenty of so it stops the production of |
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| 17:22 | C. Th or the release of . C. Th there's a nuance |
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| 17:26 | . Sometimes it's released. Sometimes its . Sometimes it can be both. |
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| 17:30 | right, so we don't need to about that. That's something you learn |
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| 17:32 | endocrinology. Alright. And then what gonna do is if you down regulate |
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| 17:36 | presence of this and the blood then can't activate the target tissue. |
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| 17:41 | So it looks a lot like But what we also have is we |
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| 17:44 | this long loop that goes even So this same cortisol which is acting |
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| 17:48 | this level also acts at the highest and says to the hypothalamus, oh |
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| 17:52 | the way just in case I want to stop releasing the releasing hormone if |
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| 17:57 | have no releasing hormone I have nothing uh anterior pituitary. If nothing stimulating |
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| 18:03 | anterior pituitary I can't make the C. T. H. In |
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| 18:07 | case. Or that that tropic hormone I'm regulating at two different levels. |
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| 18:12 | at a high level and the near . Right? And then this hormone |
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| 18:18 | what it does. It also has short loop from the anterior pituitary. |
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| 18:21 | feed back to the hypothalamus. So regulating another way. So as a |
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| 18:25 | . Th goes up in this case also acting on crH so I'm regulating |
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| 18:29 | a short loop just above me. . That kind of makes sense. |
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| 18:34 | . So this is a very very thing. So you can imagine if |
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| 18:39 | looking at gonadotropin releasing hormone, what we be regulating down here? Good |
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| 18:50 | in L. H. Right. then you can imagine downstream FSH is |
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| 18:55 | a release of a hormone. Let's of one that would be releasing, |
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| 19:01 | this is not a it's not an one. I'll go to L. |
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| 19:04 | . Because it be easier. LH a release in both males testosterone in |
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| 19:09 | estrogen. So what would those two be doing? They'd be acting negatively |
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| 19:15 | that way. Now I'm just gonna you now estrogen, the nuance there |
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| 19:19 | like whack a doo. So when get there, trust me we'll get |
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| 19:22 | the wacka do stuff because there is of control that are just crazy and |
|
| 19:32 | . Are we good with this feedback ? Yeah. So, so |
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| 19:39 | So positive feedback would be raising So let's imagine a temperature, |
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| 19:45 | So your your body temperature right now what? 37°? You remember we're scientists |
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| 19:52 | speak in C. Okay, Alright. Actually the truth is it's |
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| 19:58 | closer in 97 point something because over course of history it seems like we |
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| 20:04 | have always had infection. And so body temperature is naturally thought of as |
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| 20:09 | high. It's supposed to be about , 97. That was kind of |
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| 20:13 | that came out a couple of years . So anyway, so if you're |
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| 20:17 | 97 point something, you're actually closer normal. Alright, so you begin |
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| 20:22 | , you actually get an infection. positive feedback would be saying, I |
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| 20:26 | to move in the direction. as my body temperature rises, I |
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| 20:29 | my set point close, I mean and further away from my actual start |
|
| 20:34 | . So my temperature goes up. causes the loop to cause the temperature |
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| 20:38 | go up, which caused the temperature go up, which cause the temperature |
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| 20:40 | up and it just keeps going higher higher and higher. That would be |
|
| 20:44 | of positive feedback loop. It's kind like a ball or snowball being rolled |
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| 20:49 | a hill, snowball gets bigger and and bigger. Something from the outside |
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| 20:52 | the system has to come along and it off. All right. And |
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| 20:56 | we'll see positive feedback loops primarily in female reproductive system for and also its |
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| 21:05 | and delivery as well as in the cycle with regard to estrogen levels. |
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| 21:09 | is why I said it's wack a because it's not that estrogen is |
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| 21:13 | It's just the role it plays in is contrary to what you would think |
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| 21:19 | would be. You think, when it goes up and these would |
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| 21:21 | down now, it doesn't do all stuff. It actually has a positive |
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| 21:24 | loop. But we don't need to about the day we get to move |
|
| 21:27 | to electricity. You guys taking physics ? I asked that question already about |
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| 21:33 | optics right? Wasn't wasn't physics to circuits and electricity. And yeah, |
|
| 21:39 | people are nodding their heads rest just kind of looking like just get |
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| 21:42 | with it. So just a there's a reason why biology is like |
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| 21:47 | most broad in terms of all sciences everything underpins how how we learn |
|
| 21:52 | right? So we are or we within us ions which carry charge. |
|
| 22:00 | ? And so if you look at whole body, we have all these |
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| 22:03 | positive charges and negative charges. The is is that we do not have |
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| 22:07 | imbalance of charge. We have an equilibrium of charge. And so that |
|
| 22:12 | we're electrically neutral, How do we this? Touch somebody? See if |
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| 22:16 | if you electrocute them, right? if you had charge then that charge |
|
| 22:21 | move down there electrical gradients. Now saying that dr wayne. If I |
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| 22:26 | my feet around a little bit, can go up to somebody and shock |
|
| 22:29 | . No, no. What you've is you've built up charge on the |
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| 22:31 | of your body that isn't being discharged that other person, which is a |
|
| 22:35 | of fun. I might might remind . All right now, your charges |
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| 22:40 | course attract opposite charges, attract positive charges, attract each other. And |
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| 22:44 | course, you know that the same repel each other. So, I'm |
|
| 22:50 | use a lot of examples here that hope are understandable. And I know |
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| 22:54 | many of you have been locked up the last couple of years. So |
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| 22:57 | some of these things may not land as well as I want them |
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| 23:00 | All right, but you'll have to with me. I'm old now and |
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| 23:05 | don't change my examples. Alright. like the old professor now, who |
|
| 23:10 | this is the way that was a restaurant. Okay. Alright, |
|
| 23:16 | Now, separating charges requires energy, you guys ever go to a high |
|
| 23:20 | dance? Have you ever watched a try to sep separate a couple of |
|
| 23:26 | dancing and he turns around and what they do? Okay, it's just |
|
| 23:33 | a constant battle. it takes Alright. So that's what's going on |
|
| 23:37 | the body. It takes energy to those things separate. So, if |
|
| 23:41 | look right here, this is kind like what your body is, |
|
| 23:44 | That little boundary, right? There the plasma membrane, right? And |
|
| 23:49 | you look throughout this whole thing, see that for every positive charge, |
|
| 23:53 | a negative charge, right? You all that. And over here for |
|
| 23:57 | positive charges, negative charge. And what we have on either side of |
|
| 24:02 | membrane are unmatched charges. Now, way I like to describe this, |
|
| 24:07 | many of you guys lived in Houston enough, You know, a little |
|
| 24:09 | about the city? All right. you know over in River Oaks? |
|
| 24:13 | are two high schools that are side side to each other. This is |
|
| 24:16 | true in a leaf. But I'm familiar with a leaf. So, |
|
| 24:18 | know, but we have two high that are literally side by side to |
|
| 24:22 | other. All right. So, have Lamar high school and right next |
|
| 24:27 | is ST john's high school. These fairly big schools. I mean like |
|
| 24:31 | a size. They might be five . I can't remember now. I |
|
| 24:35 | you to imagine for a moment uh there are couples in these schools. |
|
| 24:41 | you agree that there's probably couples in school? All right. Now, |
|
| 24:44 | gotta bear with me positive negative charges . All right. we have to |
|
| 24:49 | opposite couples. Okay, So you're gonna we're gonna go with that. |
|
| 24:54 | if that offends you, suck I'm sorry. I didn't mean to |
|
| 24:59 | it like that. I want you understand opposites. Alright. In terms |
|
| 25:03 | so in our high school we have and these couples like to hang out |
|
| 25:08 | each other, right? You know one I'm talking about? These high |
|
| 25:10 | couples? They're the they're the obnoxious , right? They're always holding hands |
|
| 25:15 | walking through the through the hallways. they got their hands in each other's |
|
| 25:19 | . You know what I'm talking And they're like, you know, |
|
| 25:22 | walk around, I love you. love you too. And they're just |
|
| 25:24 | all that stuff. It's just So you can imagine both schools have |
|
| 25:28 | , right? And then they have non couple people. I'm just gonna |
|
| 25:33 | them sad sex because they want to coupled, right? Because that's just |
|
| 25:37 | way you know, and they just of walk around and it's like there's |
|
| 25:40 | in this school for me and they kind of mope around and then I |
|
| 25:44 | you to imagine at these two high that are side by side to each |
|
| 25:47 | . There's a fence in between them they have an open campus for |
|
| 25:50 | And when I say open campus, don't mean everyone goes scattering off the |
|
| 25:53 | . I mean you can eat anywhere the campus. Okay, So at |
|
| 25:58 | they go off camp, they go into the onto the quads and into |
|
| 26:02 | fields and stuff like that. And can imagine what other cute couples |
|
| 26:06 | I love you. I love you . You want to put in my |
|
| 26:08 | butter sandwich, You know, just whole gross nastiness thing. Right? |
|
| 26:13 | then that little couple that that little sack walks out with their little bag |
|
| 26:17 | and they walk outside and they look there across the fence there's an opposite |
|
| 26:28 | they smile and they see that And what do they do? They |
|
| 26:33 | up to the fence and on this of the fence they're staring across and |
|
| 26:37 | the other side of the fence is opposite one staring across the fence. |
|
| 26:42 | so creepy. But it's kind of the It might be creepy. |
|
| 26:49 | but that's what your charges do. charges are attracted to each other, |
|
| 26:55 | they're being separated by the plasma Alright, So when we talk about |
|
| 27:02 | cells and these environments inside and outside cells having charge, it's not the |
|
| 27:09 | that has charge. It's the nearby to that plasma membrane where those opposite |
|
| 27:16 | attracted ions have have accumulated. And they're basically they're desperate. How |
|
| 27:22 | we get these charges together? What we need to do if this was |
|
| 27:26 | gate? And you had all these sitting there with their little sad lunches |
|
| 27:30 | at each other. How do we these poor souls together so that they |
|
| 27:33 | find joy and happiness. Open the . That's all you gotta do. |
|
| 27:38 | open up the gate and these things gonna start moving now, positive charges |
|
| 27:41 | move towards negative charges. So, see an influx of positive charges in |
|
| 27:46 | and then everything would balance out Right? Yeah. No, it's |
|
| 27:52 | So, the rule of thumb is charges always move to negative. Does |
|
| 27:57 | actually happen? No, I we're talking current as a moving |
|
| 28:01 | So, but that's the way we're the game. Okay. That's that's |
|
| 28:05 | I was taught it. That's the the books referred to it. |
|
| 28:08 | we're just That's what we're saying. right. So, it's a movement |
|
| 28:12 | positive charges towards negative charges. So, that's where our starting point |
|
| 28:17 | . All right. So, the potential is simply the separation of those |
|
| 28:21 | charges. So, when you hear word, membrane potential, it's saying |
|
| 28:25 | got these things that want to get , but they're being held apart by |
|
| 28:28 | plasma membrane. The membrane itself carries charge. It's just the ions on |
|
| 28:33 | side desperately wanted to get to each . They have potential energy. Hence |
|
| 28:38 | term membrane potential. Alright, The in charge is basically that little region |
|
| 28:45 | I showed you right over here. . So, when we're measuring |
|
| 28:48 | that's what we're looking at? We're at the difference between those two sides |
|
| 28:51 | that little area. All right. electrical chemical gradient is the effect of |
|
| 28:57 | the concentration and the electrical gradient. . And so we're gonna get into |
|
| 29:01 | a little bit more. But remember we said we have lots of sodium |
|
| 29:04 | the outside of the cell, very sodium on the inside of the |
|
| 29:07 | So, there's a chemical gradient, that's not the only eye on that |
|
| 29:11 | in the body. We're gonna see whole list of them here in just |
|
| 29:13 | second. So, we have to not only the chemical charge, but |
|
| 29:18 | electrical charge. Now, let me show you for Well, I'll show |
|
| 29:22 | what I do potassium I think I a pretty good example of here that |
|
| 29:25 | can work with to demonstrate this more . But basically these two gradients are |
|
| 29:31 | in opposite directions of each other. so there's going to find a balance |
|
| 29:35 | the two when movement occurs and there's be a point where movement of ions |
|
| 29:39 | because those two opposing gradients meet a point. All right now we refer |
|
| 29:48 | the membrane potential being at rest or we call the resting membrane potential. |
|
| 29:53 | we find there is no net movement ions, in other words, when |
|
| 29:56 | look at a cell and those ions basically found a steady state, that's |
|
| 30:02 | we're at our resting membrane potential. cells have a resting membrane potential. |
|
| 30:07 | cells can use their membrane potential for current. Alright, so, |
|
| 30:17 | right here is a big giant list most of the uh ions that are |
|
| 30:21 | kind of important in terms of membrane and resting membrane potentials. However, |
|
| 30:26 | this big giant list. If you know these uh these the first |
|
| 30:30 | you should know, right? This If you don't know that one, |
|
| 30:33 | bicarbonate. That's just one that you kind of pick up and learn and |
|
| 30:38 | , you know, get tested to body, Right? And then this |
|
| 30:41 | right here, depending on which book gonna use. You'll see an a |
|
| 30:45 | or P R minus that refers to proteins. And so, the cellular |
|
| 30:49 | for the most part are negatively Hence an ionic cellular protein. That's |
|
| 30:55 | the A or you can say pr matter which an ionic cellular proteins. |
|
| 31:00 | right. Of all these things. of them are really important. One |
|
| 31:04 | kind of important. All right. three things that are important are sodium |
|
| 31:08 | and the antibiotics, proteins. They the ones that are largely responsible for |
|
| 31:14 | this electrical potential that we're gonna be about. All right. So, |
|
| 31:19 | is kind of a nice little chart , don't memorize everything. But you'll |
|
| 31:22 | seeing why it's kind of important to at this chart. But what I |
|
| 31:26 | do is I want to talk about briefly this electrical and this chemical |
|
| 31:30 | Alright, focus on potassium first. , So, here is a um |
|
| 31:40 | an artificial environment. And what I do is I want to say |
|
| 31:42 | we got a cell inside the You can see we have lots of |
|
| 31:45 | , we have lots of these anti proteins outside lots of sodium and lots |
|
| 31:49 | chlorine. If you look up do you see any difference in charge |
|
| 31:53 | the inside or outside the outside? neutral inside? Electrically neutral inside the |
|
| 32:00 | then has the same number of positive charges. So everything here is electrically |
|
| 32:04 | . But if we take and put leak channel for potassium, potassium is |
|
| 32:09 | leak out. Now, what we've , you can already see even though |
|
| 32:13 | here we have electrical electrical neutrality. ? Electrical Yeah, I guess that's |
|
| 32:19 | . Electrical neutrality. We really have massive gradient. We have four potassium |
|
| 32:25 | . We have zero potassium ions. ? So, when I put that |
|
| 32:27 | channel, potassium is gonna want us go sprinting out of that cell as |
|
| 32:31 | as they can until when just think potassium only two and two. |
|
| 32:36 | That's fantastic. That's what we're looking . Two and two. Right? |
|
| 32:39 | every time a potassium leaves it takes it a charge. So, as |
|
| 32:44 | leaves, the inside of the cell more negative, the outside becomes |
|
| 32:48 | Right? And there's gonna be a when that next potassium potassium island, |
|
| 32:52 | goes outside goes alright, I'm going towards my equilibrium chemical but then it's |
|
| 32:58 | to see that negative charge and go you know, I'm kind of a |
|
| 33:00 | to that negative charge but I really this chemical charge over here or chemical |
|
| 33:06 | of equilibrium. No, no, want to be over here and so |
|
| 33:08 | going back and forth and now you've that point of equilibrium, right? |
|
| 33:14 | that point when the charge in the gradient cross. And we can calculate |
|
| 33:20 | out a couple of weeks ago or last week, a couple of days |
|
| 33:25 | we talked about the nurse equation. said here's the nurse equation. Don't |
|
| 33:29 | memorizing it. You remember me mentioning . Isn't that funny how you memorize |
|
| 33:33 | ? I tell you not to memorize least you remembered what it was. |
|
| 33:37 | don't actually. The nurse equation is based on concentrations to determine what the |
|
| 33:46 | constant is. For every eye on you gotta do is know the concentrations |
|
| 33:50 | its valence and you can determine at point at what charge the difference between |
|
| 33:57 | environment and that environment will you reach where that ion is sitting there going |
|
| 34:02 | and forth and can't decide which way go. All right, Where those |
|
| 34:08 | things have equal liberated. Now we have to do the math here, |
|
| 34:15 | goodness. There are some physiologists who make you do the math. |
|
| 34:21 | I saw that. I saw you know. Alright, so here |
|
| 34:25 | is again, you can kind of this is trying to show that sodium |
|
| 34:30 | the same thing, right? We a leak channel in we know |
|
| 34:34 | And what we can find is that point where the movement of sodium stops |
|
| 34:39 | when the inside of the cell becomes at 60 million volts for potassium, |
|
| 34:44 | happens to be about negative 90 million . So, it's basically when the |
|
| 34:48 | of the cell is negative 90 million , That's when that movement stops the |
|
| 34:53 | of sodium into the cell. Because have lots and lots of sodium on |
|
| 34:56 | outside of the cell stops when the cell becomes plus 60. That's what's |
|
| 35:01 | , okay, I've done enough and I'm everything is kind of imbalanced for |
|
| 35:06 | . So, each ion has its equilibrium potential. The thing is, |
|
| 35:14 | that what we just looked at um aren't the only things that are |
|
| 35:19 | remember. So, if if sodium into the cell, it's moving down |
|
| 35:24 | grade and we have a pump that's saying no, no, no, |
|
| 35:27 | , no, I want to take of you and I want to kick |
|
| 35:29 | back out and that same pump is saying no, no, I'm grabbing |
|
| 35:32 | of those potassium that leaked out and putting it back in. So there's |
|
| 35:36 | constant flow of sodium as it's trying get to that plus 60 and there's |
|
| 35:42 | constant flow of potassium out of the just trying to get the inside of |
|
| 35:45 | cell of -90. These two things battling each other. Plus we got |
|
| 35:49 | thing sitting there pumping, pumping, , pumping, saying no, you |
|
| 35:52 | back where you started. It's like to herd kittens or something. |
|
| 35:57 | This accounts for roughly 20% of the potential. sodium has a role. |
|
| 36:05 | has a role A. T. . S. Has a role. |
|
| 36:11 | . Like I said, we could it out nurse equation. We could |
|
| 36:14 | and do the math and figure it if you want to. You can |
|
| 36:16 | back and look up the equation and it yourself. How many of you |
|
| 36:19 | to actually do that math nerds? math nerds. All right. You |
|
| 36:24 | admit it if you want to. can't I'm not gonna stop you. |
|
| 36:28 | right. The thing is, is of our cells just have sodium or |
|
| 36:32 | have potassium. They have sodium potassium , calcium, phosphates, bicarbonate, |
|
| 36:39 | antibiotic cellular proteins. They have all these things. So, everything has |
|
| 36:43 | effect on that membrane potential. If have a leak channel something's moving the |
|
| 36:50 | thing that can't move in and out the cell cellular proteins because they're too |
|
| 36:54 | . So, there's always gonna be negative charge kind of on the inside |
|
| 36:58 | the cell. So, we have take everything into account. But |
|
| 37:03 | of all the things, only the potassium neonics, all your proteins have |
|
| 37:07 | biggest make the biggest deal. Now , I'm going to focus on numbers |
|
| 37:10 | a moment so you can see this the cell in terms of millie |
|
| 37:14 | So this is millie moller, 150 15. So tenfold difference to ask |
|
| 37:20 | 150 versus five. So on the there's in terms of antique cellular proteins |
|
| 37:28 | , right? Because you don't have other side, hence named cellular |
|
| 37:33 | But the thing that makes the biggest in terms of effect has to do |
|
| 37:37 | permeability. Permeability simply is the number channels that are open and available for |
|
| 37:44 | for those particular ions. Now there's whole a whole equation that you can |
|
| 37:52 | and I don't think I even required to read over it in the textbook |
|
| 37:55 | you want to hear see the Hodgkins Cats, thank goodness. But basically |
|
| 38:02 | it's the nurse equation like, like steroids where they throw in permeability as |
|
| 38:08 | and it just says, look, has an effect. Now you already |
|
| 38:13 | this, I'm gonna I'm gonna prove you know this, you guys been |
|
| 38:15 | a sporting event. Alright, It's halftime, let's say it's a |
|
| 38:20 | game. It's halftime. Everyone gets and goes down to the bathroom |
|
| 38:24 | how long did it take you to through the line at the bathroom, |
|
| 38:28 | to the guys a couple of minutes out, go get yourself a |
|
| 38:33 | go get yourself a beer, get some nachos, go hang out with |
|
| 38:36 | couple of friends, go back to seats, go scream and yell for |
|
| 38:39 | little bit ladies. When you get to the game, 54 might not |
|
| 38:45 | it backs, might be at the quarter. You don't know right? |
|
| 38:49 | reason has to do with permeability now sitting away. What do you mean |
|
| 38:53 | ? What do you mean? All , I'm gonna give away some secrets |
|
| 38:56 | . I mean this is a physiology . We need to know how each |
|
| 38:58 | each other's works when we go into restroom in the men's restroom, you're |
|
| 39:02 | speaking, there's usually a trough. And usually what that means is that |
|
| 39:07 | halftime 80 men line up to these that can probably comfortably fit three |
|
| 39:13 | And what we do is we jam there and we look I forward and |
|
| 39:16 | do our business and we calmly step and then walk away and just pretend |
|
| 39:21 | this never happened. Right ladies, have stalls and so you might have |
|
| 39:27 | stalls in the restrooms. So if are 80 women waiting to get |
|
| 39:31 | you have to cycle eight whole cycles get all of you through again for |
|
| 39:36 | . We just go up and do business and get out of there. |
|
| 39:39 | the reason it takes so long happens be with has to do with |
|
| 39:43 | There is more opportunity for us to a restaurant than you do, if |
|
| 39:47 | makes sense. Okay, That's kind what's going on here with regard to |
|
| 39:53 | cell and the effect that these things . So permeability has an effect. |
|
| 39:58 | , the way to read this is permeability basically says, look for every |
|
| 40:03 | channel. So one sodium channel, are roughly 50 to 75 potassium |
|
| 40:09 | Right? So, that means the of potassium out of the cell is |
|
| 40:14 | faster than the flow of sodium into cell. Alright, So, if |
|
| 40:19 | is leaving quickly, what am I behind? What charges it? What |
|
| 40:26 | potassium positive? So, what am leaving behind? A negative charge. |
|
| 40:30 | right. And so even though I'm in positive charges, it means for |
|
| 40:34 | 50 molecules potassium that leave one molecule sodium goes in to replace it. |
|
| 40:39 | the inside of the cell is becoming and more negative. Right, relatively |
|
| 40:49 | . Yeah, Sorry, that's And thank you for looking. |
|
| 40:53 | that's important. If the orange light off, we're all screwed. |
|
| 40:56 | So, permeability matters. It tells the effect. And so, you |
|
| 41:02 | , given the given the first equation equilibrium potentials and stuff, what we |
|
| 41:06 | then say is that the membrane of cell, the resting membrane of the |
|
| 41:10 | is mostly affected by which of those . Which one do you think of |
|
| 41:16 | three potassium? And so that means membrane potential is gonna most closely look |
|
| 41:23 | potassium. Now, I'm just pointing the numbers. So, it's not |
|
| 41:26 | here, the membrane Petrolia, it's there at the top of the membrane |
|
| 41:30 | or the equilibrium potential for potassium is 90. The equilibrium potential plus 60 |
|
| 41:35 | um sodium, the membrane potential for neuron minus 70. All right. |
|
| 41:42 | see how it looks a lot closer , these aren't the only two chlorine |
|
| 41:46 | an effect as well, calcium can effect as well. It just depends |
|
| 41:50 | what legal channels and what ions happen be on the cell. And in |
|
| 41:53 | case of neuron chlorine is resting equilibrium that roughly -70. So basically, |
|
| 41:59 | almost there already. Yeah. So, just to be clear as |
|
| 42:12 | can hear him when we see this up here, am I ignoring everything |
|
| 42:16 | in the cell? Absolutely. when you're dealing with the nurse, |
|
| 42:20 | can see equilibrium equilibrium potential for potassium . So, when you're considering anything |
|
| 42:26 | , that's when you use that other that we're it's gonna be the voldemort |
|
| 42:30 | here. We're just gonna say the that should not be named C H |
|
| 42:34 | H G K equation. Alright. what that basically does, it allows |
|
| 42:38 | to figure out where that membrane So, you could in theory calculate |
|
| 42:42 | membrane potential if you happen to know the concentrations inside and outside the cells |
|
| 42:47 | each of those ions or as well their permeability. Alright. And this |
|
| 42:52 | what some physiologists do for fun. you imagine those types of parties? |
|
| 42:57 | right. So, this just kind summarizes everything that we said. All |
|
| 43:01 | . So, look, if if cell has a membrane potential of |
|
| 43:06 | which is what I told you, is -70, that is a |
|
| 43:10 | That is the result of all of different effects. But it's also not |
|
| 43:17 | to counterbalance. So, if I'm -70, I still haven't reached equilibrium |
|
| 43:21 | potassium. So potassium still wants to out of the cell, doesn't |
|
| 43:25 | It'll keep moving out of the cell it reaches -90. Alright. Same |
|
| 43:30 | . My cell here is at but the sodium is going to move |
|
| 43:36 | the cell until it reaches the inside plus 60, which it is nowhere |
|
| 43:41 | . So, it's gonna constantly move and so you constantly have these ions |
|
| 43:46 | across the membrane. And then what the pump doing? Go back to |
|
| 43:51 | I put you and it just keeps that. And so That -70 represents |
|
| 43:57 | in balance. Okay, Okay, big deal. Yeah. And then |
|
| 44:10 | . Okay. All right. if you have a whole bunch of |
|
| 44:13 | charges leaving All right, let's do this way. Maybe this maybe this |
|
| 44:17 | be a little bit clear cause I want to keep saying the same thing |
|
| 44:19 | and over again. You have a and let's say you have an equal |
|
| 44:23 | of men and women. All It's a perfect party. Never |
|
| 44:27 | Perfect parties. Equal number of men women. Half the women leave. |
|
| 44:31 | do you have now? Mostly I'm surprised you didn't say sausage |
|
| 44:37 | Alright. But yeah, mostly All right. So, what you |
|
| 44:42 | now is you have an imbalance. ? That's that's what we're saying. |
|
| 44:45 | even if you had a door where the women were leaving and one woman |
|
| 44:48 | coming back in to replace, you still end up with more men at |
|
| 44:52 | party. Right. And that's kind the same thing that's going on here |
|
| 44:55 | there are more opportunities for potassium to because there's more leak channels by number |
|
| 45:00 | to 50 or 50 to 1, means for every 50 or every sodium |
|
| 45:05 | comes in, 50 potassium are leaving that's why the inside is becoming more |
|
| 45:09 | more negative. Right? So, to be clear, because this could |
|
| 45:13 | a terminology thing is that negative doesn't mean negative charge. It could also |
|
| 45:19 | a lack of positive charge. So, just in this case, |
|
| 45:23 | happens to be a negative charge because have the cellular proteins. They're |
|
| 45:27 | But whenever you hear the movement of of sodium or sorry, movement of |
|
| 45:31 | charges, you're leaving behind negative you're no longer an equilibrium. Alright. |
|
| 45:43 | gotta make sure there's a lot of on this one. Oh, there's |
|
| 45:46 | evil? It's G H K. H G K. But same |
|
| 45:49 | I give them credit. Um So generated. So this is basically membrane |
|
| 45:55 | we already said is generated by those gradients, right? And their movement |
|
| 46:00 | on the relative permeability which we talked . And then any sort of changes |
|
| 46:04 | going to have some terminology to Alright, first is that if you |
|
| 46:09 | a positive change in in the membrane , we refer to that as a |
|
| 46:12 | polarization. All right. And then negative change would be a hyper |
|
| 46:17 | Now let me explain what this is this. You guys remember third grade |
|
| 46:21 | you started learning number lines remember number . Those are the best things |
|
| 46:25 | Because everyone could get those right. for my son who struggles. He |
|
| 46:30 | absolute values. Just fine. He can't figure out negative numbers. All |
|
| 46:37 | , Here I am. I'm on . If I'm at zero, I'm |
|
| 46:42 | we call neutral. Right? I no Charge one way or the |
|
| 46:49 | Right. If I move in the way, right facing you guys, |
|
| 46:54 | no longer neutral, I am Right? I'm positive. I'm polarized |
|
| 47:00 | ? I have polarized away from neutral neutrality. Come back over here to |
|
| 47:06 | . If I move in the negative , I have polarized again. Haven't |
|
| 47:11 | ? All right. So in our we have no cells that sit at |
|
| 47:17 | . Alright. They're all polar in way shape or form. Typically the |
|
| 47:21 | of cells are more negative. So when you look at a cell they're |
|
| 47:25 | over here in a polarized state. the negative. You know, in |
|
| 47:29 | sort of negative value. So if a neuron this would be minus |
|
| 47:32 | If I was a cardiac cell, might be minus 55 or something like |
|
| 47:36 | . Okay, So if I move zero, I have become more or |
|
| 47:43 | polarized. Less polarized. So if becoming less polarized, I am deep |
|
| 47:50 | . Right? And then if I back to my original polarized state, |
|
| 47:53 | have re polarized. And then if become more polarized, Hyper polarized now |
|
| 48:01 | that terminology over here, That's that's and stuff. But I mean it's |
|
| 48:04 | over here too. Right here I at zero Now I become positive and |
|
| 48:07 | polarized in the polaroid in a positive as I move towards zero, I'm |
|
| 48:14 | more or less polarized less. So become yes, I was like |
|
| 48:23 | but yes, you're right. And I returned back I am. And |
|
| 48:27 | if I go further away I am , now the only place where this |
|
| 48:32 | not work. Alright, is when talking about passing over zero. |
|
| 48:38 | And we just what we do is talk about like here I am in |
|
| 48:41 | deep I mean my I mean my state. I'm deep polarizing as I |
|
| 48:45 | toward zero. If I pass zero keep going I continue in that same |
|
| 48:50 | same movement. So we just continue refer to it as being D |
|
| 48:54 | And then I re polarize back to I'm going. Alright, So that's |
|
| 48:58 | only time. So when you see polarization, we talked about an action |
|
| 49:01 | potential goes over zero because it will gonna be going wait a second. |
|
| 49:05 | just told me these words and I'm yeah, yeah, yeah. |
|
| 49:07 | So, we're good with that. right. This is where we pause |
|
| 49:20 | some nervous system stuff before we jump face first into the action potential. |
|
| 49:29 | . So the nervous system in a very brief definition is simply a bunch |
|
| 49:35 | nerve cells. Just a bunch of . A couple billion. Right? |
|
| 49:40 | what they are. They're linked in sort of organized manner so that you |
|
| 49:44 | control different things in your body. nerve cells we call them neurons. |
|
| 49:50 | the ones that are responsible for producing signals along their length so that they |
|
| 49:56 | tell another cell what to do. right now. So that you can |
|
| 50:01 | this picture your pinky to make your move. There's a neuron that leaves |
|
| 50:09 | spinal cord and that neuron travels the length of your arm down to that |
|
| 50:15 | so that you can wiggle it. right. It's causing the release of |
|
| 50:19 | chemical at the end of that neuron the neuron and muscle. But the |
|
| 50:24 | signals traveling the length of the cell is as long as your arm |
|
| 50:27 | Okay. So the electrical signal This is not electrical signaling in the |
|
| 50:31 | that I'm telling an electrical I'm not the electoral signal from one cell to |
|
| 50:35 | next. It's electrical in the sense I'm using that distance to cover that |
|
| 50:40 | . Um with an electrical signal right the length of the cell. Now |
|
| 50:46 | cells will use gap junctions to allow signals to travel. That's primarily in |
|
| 50:53 | central nervous system if you have And then when we talk about the |
|
| 50:56 | we're gonna see cells that do that well. And smooth muscles can do |
|
| 51:00 | as well. But we're focused on nervous system right? So most of |
|
| 51:04 | signaling that we're gonna be dealing with gonna be chemically signaling. But to |
|
| 51:08 | to that chemical signal we're gonna use electrical impulse to trigger the chemical |
|
| 51:14 | Now, the nervous system isn't fully up of neurons. It also has |
|
| 51:19 | cells that we refer to as glial or neurons glia as you'll see it |
|
| 51:23 | it looks like neuro glia but we to sound hoity toity and fancy. |
|
| 51:27 | it's neuro glia. Alright. It's it's pronounced. They don't play a |
|
| 51:32 | directly in the transmission electrical impulses. are like all the support cells that |
|
| 51:37 | can possibly imagine now. This is favorite time of year because it's football |
|
| 51:42 | and I can live just watching football eating mexican food. Those two |
|
| 51:47 | That's all I did for the rest my life without gaining weight would be |
|
| 51:52 | , really awesome, right? But like to use football analogies, especially |
|
| 51:56 | . So if you don't like you better learn a little bit about |
|
| 52:00 | . Each side of a football team how many players? two teams. |
|
| 52:07 | teams. How many on the 11. 11 per side. |
|
| 52:13 | so if you like soccer, you use that as well. Alright. |
|
| 52:16 | the reason I pulled the point this to you is because the ratio of |
|
| 52:22 | to neuro glia Uruguay is 10-1 now is the most important player on the |
|
| 52:30 | ? Quarterback? Right, quarterback, , quarterback is a star quarterback is |
|
| 52:36 | one that everyone focuses on quarterback, , quarterback, quarterback. Unless you're |
|
| 52:40 | , in which case you don't want talk about your quarterback anymore. |
|
| 52:45 | If you don't know that story. left Auburn, you know, went |
|
| 52:49 | Oregon because he's gonna be a superstar and just Yeah, no, |
|
| 52:56 | no, no, no, we're talking about kickers today. Yeah, |
|
| 53:01 | , but well, the kicker can the game for you, but but |
|
| 53:06 | me, let me use my analogy alright, because it's, it's simplified |
|
| 53:11 | I'm gonna point out here that the is useless, if he has no |
|
| 53:17 | , quarterback is useless. If he no receivers to catch the quarterback can't |
|
| 53:23 | the ball, right, He needs have that line. And if he's |
|
| 53:27 | hand off that ball, he needs have someone blocking forum. So everything |
|
| 53:31 | makes the quarterback look fantastic with the hair, you know, and just |
|
| 53:37 | awesome is a function of all the players on the field. And if |
|
| 53:42 | ever played football, you've heard this over and over. There is no |
|
| 53:47 | in team, there's there's a but there's, but you have to |
|
| 53:53 | the letters around a lot. And that's the same thing. That's |
|
| 53:57 | here. So when you think of brain, yeah, you got important |
|
| 54:02 | that are doing stuff there. The , they're the sexy sells. But |
|
| 54:06 | every one of them there's 10 of making that happen. Okay. And |
|
| 54:10 | are the glial cells or the neuro . Now as humans. And as |
|
| 54:20 | , we like to make things I mean, your life may not |
|
| 54:24 | organized. Your room may not be , but there's something that you do |
|
| 54:28 | have that is incredibly organized, I don't know what it is, |
|
| 54:33 | we all have it. Okay. so with scientists, we do the |
|
| 54:38 | thing when you look at the nervous , nervous system is a very complex |
|
| 54:42 | , it's very, very difficult to . In fact, if you find |
|
| 54:46 | this stuff fun and interesting after we this. I highly recommend the neurobiology |
|
| 54:51 | or the neurophysiology class of doctors. teaches because it goes into a lot |
|
| 54:55 | depth than what we're gonna cover. right. But one of the things |
|
| 54:59 | scientists do like to do is we to take things that are complex, |
|
| 55:02 | them apart and drop things into All right now, I'm not saying |
|
| 55:06 | this is entirely the best way to stuff, but this is one of |
|
| 55:09 | ways that we organize things and that's we've done is we say look, |
|
| 55:12 | we look at the nervous system, has two parts, it has a |
|
| 55:14 | nervous system. That's the yellow in little cartoon up here, This is |
|
| 55:18 | brain and your spinal cord the Alright. So everything that's brain and |
|
| 55:23 | that spinal cord is central nervous that means everything else. Outside of |
|
| 55:27 | two things are the peripheral nervous Alright. So everything that's blue in |
|
| 55:32 | little picture is the peripheral nervous Alright, So what we're talking about |
|
| 55:37 | , when we say peripheral that's information goes in that delivers information to the |
|
| 55:41 | nervous system, the central nervous system information and then information leaves the central |
|
| 55:46 | system via the peripheral nervous system. it's the information out to the things |
|
| 55:50 | are responding to the things that you receiving, right? So information going |
|
| 55:56 | is referred to as the different division leaving is the different now outside of |
|
| 56:04 | people will say um different and I don't like doing that because in |
|
| 56:08 | different and different sound an awful lot . So different and different is how |
|
| 56:13 | do it here. But if you it otherwise, just remember I'm trying |
|
| 56:16 | avoid that horrible texas twang. so A. And E. A |
|
| 56:21 | is out. All right. And if you look at the different |
|
| 56:26 | we're asking where is that information Actually all of these can be kind |
|
| 56:29 | broken down. And is we have is referred to as the somatic and |
|
| 56:32 | is the autonomic? Typically when we're about the somatic nervous system, we're |
|
| 56:36 | about the motor neurons. So these the things that cause movement in the |
|
| 56:40 | . They innovate the skeletal muscles. we'll get to what the somatic parent |
|
| 56:44 | in just a moment. But there a somatic portion of the different system |
|
| 56:48 | as there is a visceral component. , so somatic deals with movement. |
|
| 56:53 | pretty easy. And that means everything when it comes to going systems going |
|
| 56:58 | are things that are autonomic things you control, you can't control how much |
|
| 57:03 | salivate you can't control how your smooth contract. This is especially true around |
|
| 57:09 | when you're in a class and you eaten, you've heard those noises |
|
| 57:14 | right? As your body is sitting dumping out tons and tons of enzymes |
|
| 57:20 | , I expect food you haven't I'm gonna let you know. |
|
| 57:25 | And the muscles are sitting there churning , there's nothing to turn here. |
|
| 57:29 | muscle. Alright, let's we're friends , right. We can talk about |
|
| 57:32 | stuff. How have you ever come that that crush? You know, |
|
| 57:37 | they actually come up and start talking you, You know, and you |
|
| 57:41 | want them to know and you just there going doing this sort of |
|
| 57:47 | And your son, Huh? Uh . Not hearing a word you're |
|
| 57:51 | Just can't agree. Right? I control that cardiac muscle. So this |
|
| 57:58 | involuntary nervous system and it breaks down the sympathetic and parasympathetic, which is |
|
| 58:03 | and flight. Fight or flight and and digest. We'll get to that |
|
| 58:07 | the next unit. All right. you can see what we've done is |
|
| 58:09 | taken this system and we've broken it into some categories that we can easily |
|
| 58:15 | . But what I want you to while we're breaking it down to |
|
| 58:18 | Everything is integrated. So, if focusing on the sympathetic, understand parasympathetic |
|
| 58:22 | going on at the same time. you're talking about the somatic system. |
|
| 58:26 | there's stuff that's going on in the all the time. Everything is on |
|
| 58:30 | the time. Everything is doing what needs to do. We're just kind |
|
| 58:33 | focusing and it's like looking at a engine running and pointing out a part |
|
| 58:37 | just saying what does this one thing ? Nothing works independent of the |
|
| 58:41 | Yeah. Yes. So typically what do is we just refer to it |
|
| 58:50 | part of the autonomic part of the . Does that mean that it only |
|
| 58:55 | that side note, there's gonna be that you receive, but we don't |
|
| 58:59 | say, oh that's just a matter that's a sympathetic uh sensory system. |
|
| 59:05 | it acts in that way you're receiving input and it's acting specifically on sympathetic |
|
| 59:14 | . Another question, No, we're gonna do that. It's it's fight |
|
| 59:19 | flight rest versus digest. So maintaining your regular uh regular homeostasis versus |
|
| 59:28 | happens under the conditions of emergency exercise excitement. We're not doing that |
|
| 59:35 | Unit two at the end of unit when we're really kind of trying to |
|
| 59:39 | through stuff. What's that? I'm smart. I got my I |
|
| 59:45 | my brought my phone up this Yeah, I stopped wearing watches like |
|
| 59:49 | years ago and it's hard now. . In terms of the neuron. |
|
| 59:53 | , what I wanna do is I to point out a couple structures to |
|
| 59:55 | have the cell body also called the carry on, also called the |
|
| 59:59 | It has so many names because neurobiologists they're special. And so they just |
|
| 60:03 | things, especially this is where all organelles are. This is the machinery |
|
| 60:06 | the cellular machinery is gonna be So everything that the cell does is |
|
| 60:10 | be made inside the cell body and that stuff is sent onward to the |
|
| 60:14 | places. The dendrites are the receiving of the cell. Does that mean |
|
| 60:19 | the only portion that receive information? , but it is the primary receiving |
|
| 60:24 | of the cell here. We're going produce grated signals that are going to |
|
| 60:28 | used to create triggering events that are to result in action potentials Axons |
|
| 60:33 | So if you look at this, is dendrites, the little tiny ones |
|
| 60:36 | the dendrites. The very long one the axon. The axon begins at |
|
| 60:40 | at the axon hillock contains voltage gated that are going to allow for the |
|
| 60:45 | of the action potential. Lastly, axon terminal, which is down here |
|
| 60:50 | the end um These terminals um have the end of them. Really called |
|
| 60:55 | dri a. This is where the is at the very very bottom. |
|
| 60:58 | is where you release the chemical So, the axons are gonna be |
|
| 61:02 | things that are long. So depending how far you need to travel, |
|
| 61:05 | it's gonna be a millimeter or whether gonna be uh several meters. Presuming |
|
| 61:09 | big and tall, uh they're gonna different lengths and that's what that electrical |
|
| 61:14 | is going to be using. ma'am. Yes. So, so |
|
| 61:21 | initial segment is considered the axon hillock this case, is that not what |
|
| 61:25 | say up here? That's yeah, gonna be uh the initial segment typically |
|
| 61:30 | referred to as that axon hillock. different authors are starting to use initial |
|
| 61:36 | now and again. It's this this away from this older language that is |
|
| 61:42 | to neurobiology that they're trying to to away from. But you can think |
|
| 61:47 | segment is where everything initiates. So how does the synapse work? |
|
| 61:55 | do I how do I release chemical if everything is made up here? |
|
| 61:58 | , I need to have some sort transport mechanism. And so we have |
|
| 62:02 | is referred to as axa plasma transport down, that's referred to as uh |
|
| 62:09 | , moving away as retrograde. And what I'm doing is I'm making all |
|
| 62:13 | neurotransmitter, all the signaling molecules up and then I'm transporting them via um |
|
| 62:19 | proteins down the lengths of these micro down to the end. So the |
|
| 62:25 | are are being carried, that's what should have on top of them and |
|
| 62:28 | being carried down to the end and once I release them, you |
|
| 62:32 | then they go on their way. you'll see a little bit later. |
|
| 62:36 | think in the next year you might it's it's on thursday that we also |
|
| 62:40 | stuff. And so anything that we , we're going to send back for |
|
| 62:44 | as well And there's fast and they're and which is kind of listed over |
|
| 62:48 | , but I want to kind of you not to memorize these, but |
|
| 62:50 | see what is fast is about 400 day. So how much is the |
|
| 62:59 | ? Right. And so a yard really a meter is 1000 of |
|
| 63:05 | So roughly about this far per Yeah. Uh huh. Axon |
|
| 63:16 | Axon hillock. Not the axon axon the long axon hillock. Is that |
|
| 63:21 | fat little part right here, we'll there. Yeah, I know. |
|
| 63:27 | also have the question with the pair carry on it. We didn't like |
|
| 63:34 | there are different types of neurons there based on shape, there, named |
|
| 63:39 | on the number of dendrites that they or extensions. So this right here |
|
| 63:44 | to show you some extensions. Uh you can see here, what you |
|
| 63:48 | is you just find the cell you find a number of things coming |
|
| 63:51 | it and you just count them. that would be one. That would |
|
| 63:55 | too That's more than two. So . And really this is pseudo uni |
|
| 64:02 | we're not gonna go into why right , it's uni by multi we don't |
|
| 64:07 | to actually count up the actual numbers than to just call it multipolar. |
|
| 64:12 | , so that'd be the number of here, this is just showing you |
|
| 64:17 | uh different types in terms of the projections. So you can see here |
|
| 64:23 | two there there's two there there's really is one but you count up all |
|
| 64:30 | dendrites in this particular case of the pattern. So this is referred to |
|
| 64:34 | a pyramid cell because if you look it kind of creates this pyramid |
|
| 64:37 | satellites or Stella Stella is Stella Thank you. So, star like |
|
| 64:47 | . The truth is here is that is gonna be less important for |
|
| 64:51 | We typically focus over here. This is a weird one. We see |
|
| 64:57 | in the in the central nervous system not any one of these in particular |
|
| 65:02 | as an ax on, it's basically of an intermediate cell that can work |
|
| 65:06 | between multiple cells within a larger So you can send in multiple |
|
| 65:12 | Whereas whenever you have an ax on sending in one direction. Alright, |
|
| 65:16 | you receive on this side send down way you receive on this side sitting |
|
| 65:20 | that way, presuming they're all pointing same way, receive here. Send |
|
| 65:23 | that direction here, I can receive send in any direction. I just |
|
| 65:30 | this up because I had nothing better show you. And you know, |
|
| 65:33 | like a big wall of text can confusing, but really what it is |
|
| 65:37 | that this just points out the we can we can name them based |
|
| 65:40 | based on their modality. So, know, in terms of are they |
|
| 65:44 | in or they're going out of the system. So as a parent fiber |
|
| 65:47 | an different fiber. Is it a fiber or is it a sensory |
|
| 65:52 | Right. So if it's sensory it's information in its motor, I'm sending |
|
| 65:57 | away from the central nervous system. ? Is it visceral or is it |
|
| 66:01 | ? Visceral? Whenever you see the visceral, think guts. The organs |
|
| 66:05 | my body are my viscera. So it getting information from those organs? |
|
| 66:11 | is it getting information from the surface my body or from my muscles of |
|
| 66:16 | body? So visceral um neurons are my guts. Somatic are from my |
|
| 66:23 | and my skin. So when someone me, is that visceral or is |
|
| 66:26 | somatic? Somatic? Right. So I have stomach ache, that's visceral |
|
| 66:33 | somatic visceral? Okay. And then , the third category, is is |
|
| 66:41 | a special neurons or is a general ? Special neurons are the it's it's |
|
| 66:46 | on embryonic origin but you can think special as my special senses. What |
|
| 66:51 | my special senses? Yeah. So of the monkeys, You know the |
|
| 67:04 | . Yeah, it's a good way remember it. Yeah. You don't |
|
| 67:07 | don't know the monkeys. Yeah, it's it's it's it's basically sight smell |
|
| 67:14 | right? Although with monkeys it's speak ? But its taste right? And |
|
| 67:20 | uh we also have hearing and then hearing we also have balance. So |
|
| 67:26 | audition and equilibrium. All right. if you look at that you can |
|
| 67:31 | think category one. Category 2. three. That's uh two to the |
|
| 67:36 | power or something. I can't I came up with 23 total. |
|
| 67:40 | but one of these we don't use semantically just they don't exist. So |
|
| 67:45 | don't use that term. And I'm not gonna ask you the combinations |
|
| 67:49 | when you start looking like okay I here I've got a somatic different. |
|
| 67:53 | have a visceral different you know that's to my guts and telling my stomach |
|
| 67:58 | contract from there's food there. That of thing. Man. I am |
|
| 68:03 | slow today. Even worse than Alright, glial cells. Remember we |
|
| 68:08 | they don't conduct nerve impulses. They of serve as the glue. Hence |
|
| 68:12 | name the glue that holds the brain . There's a whole bunch of different |
|
| 68:16 | . They maintain the extra cellular So uh this is kind of the |
|
| 68:23 | ones. So astrocytes. Where are ? Oh there, what do you |
|
| 68:28 | they call Master? Sites discovered in . Right. No, they're shaped |
|
| 68:34 | stars. Astra sites micro glia, micro micro glia. Why? Tiny |
|
| 68:42 | glial cells. Alright. Allah go sites. Olivo means many. It's |
|
| 68:48 | good guess right. It means Den dro are branches so many branched |
|
| 68:56 | and that's what you have is you I'll get into site, you can |
|
| 68:59 | all the branches, right? It's myelin aging cell and then the pendulum |
|
| 69:02 | sell. I have no idea where one comes from. Schwann cells named |
|
| 69:05 | the guy that discovered them? Satellite because they're around other uh nervous |
|
| 69:11 | These two are in the peripheral, other four in the central. So |
|
| 69:15 | astro sites uh they play a role physical and chemical support. So if |
|
| 69:19 | can imagine a neuron you can imagine in between creating the scaffolding, holding |
|
| 69:24 | around it and kind of creating the in which these cells are going to |
|
| 69:28 | found. They play a role in the blood brain barrier is not the |
|
| 69:31 | business bureau. Uh They act as scar tissue. So you can kind |
|
| 69:36 | see in this picture here they deliver . So here I'm picking up a |
|
| 69:40 | and I'm delivering, it has lactate the neuron which the cell uses as |
|
| 69:45 | . Um here you can see two . This is supposed to be the |
|
| 69:49 | site. Here's the neurotransmitter. I've up the neurotransmitter. I'm recycling the |
|
| 69:54 | and delivering it to the neuron. it has multiple roles in maintaining that |
|
| 70:00 | perfect environment in which that neuron uh . The myelin producing cells are both |
|
| 70:08 | good and the Schwann cell. They're in how they look and behave in |
|
| 70:13 | different systems. So all good dinner , here's your cell. They have |
|
| 70:17 | extensions, they reach out to multiple and wrap around their axons with these |
|
| 70:23 | sheaths, Schwann cells you have multiple cells. They each wraparound individually doing |
|
| 70:28 | job. And Myelin serves kind of an insulation for electrical signaling, which |
|
| 70:33 | talk about a little bit later. don't want to get lost in it |
|
| 70:35 | now. Microbes have multiple roles. one we're going to focus on right |
|
| 70:40 | is immune defense systems. They're kind like this this group of cells that |
|
| 70:45 | really kind of discovering more and more . And so but this one is |
|
| 70:48 | of like the the big one. they kind of like macrophages, they |
|
| 70:51 | of hang around and do nothing until need to do something. Right, |
|
| 70:56 | , I like this resting and then they're all 10 minutes. This is |
|
| 71:04 | . All right. We're gonna get far into this. This is up |
|
| 71:08 | . Just to remind me to remind that ions can pass the membrane cell |
|
| 71:13 | right? Where they stuck outside looking inside, looking out. Right. |
|
| 71:24 | all I gotta do is open the . Okay. That's what we're trying |
|
| 71:28 | do. First off. Action Action potentials are simply very large, |
|
| 71:35 | brief, very rapid changes of membrane . All right. We're in the |
|
| 71:42 | potential completely reverses itself. All So here we are at rest at |
|
| 71:47 | . We completely reverse the inside of cell becomes positively charged and the returns |
|
| 71:52 | down to rest again. All when this happens, what you're doing |
|
| 71:59 | you're only doing a very small portion the membrane. And what's what you're |
|
| 72:05 | at is this is a graph over . So, you can see, |
|
| 72:07 | , it doesn't show you this is over here, that's membrane potential. |
|
| 72:10 | so, what I want you to for a moment is that you're watching |
|
| 72:13 | pass and so you're watching them potential up and going down now. The |
|
| 72:18 | way I like to demonstrate this, is why I'm sad that there's only |
|
| 72:20 | minutes in because we'll have to come and do this again on Thursday. |
|
| 72:24 | I want you to imagine a Have you ever done the wave? |
|
| 72:28 | ? Alright, we're gonna do is going to propagate a wave. We're |
|
| 72:31 | start. And where does the wave that way, Let's see who's too |
|
| 72:36 | for school. I'll call you out . You don't have to actually stand |
|
| 72:39 | . But let's do it again. at that. You just did one |
|
| 72:43 | those. Alright, I want you all watch him while we do the |
|
| 72:49 | ready. Everyone watch him while we the wave. We're gonna propagate over |
|
| 72:53 | . We're gonna go that way. go. Alright. Did you see |
|
| 72:57 | happened over time? Where did his start? Bottom? And where do |
|
| 73:01 | go to the top and then they back down again. So, over |
|
| 73:07 | , our hand was down here at bottom, then it went up and |
|
| 73:11 | it came back down again and then kept going. Right. So really |
|
| 73:15 | we're looking at is we have a stuck in the cell membrane and specific |
|
| 73:19 | watching the membrane potential change. All . And when we say propagation, |
|
| 73:24 | did it do? It went from side of the room to the other |
|
| 73:27 | notice that that wave when it it didn't go higher. Didn't go |
|
| 73:31 | . It stayed the same the entire . Grant we're all different sizes. |
|
| 73:36 | you're you're all with me? sir. Small court. Mhm. |
|
| 73:44 | . So he's like just that little little point where we're measuring is that's |
|
| 73:48 | our small portion. Even though the potential went the entire length of the |
|
| 73:53 | , what we're doing there is we're at that one potential at that |
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| 73:57 | we're gonna do it the way one time. And when I say |
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| 74:00 | whatever, wherever your hands are, them. They're ready. Stop. |
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| 74:06 | . What are your hands doing? what are they doing? Are they |
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| 74:11 | coming down? What are your You're at the peak? What are |
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| 74:13 | hands doing peak. What are your doing over here? They're going |
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| 74:17 | All right. So, do you where you are? You can put |
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| 74:20 | hands you can see your at different in time. And what we're doing |
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| 74:25 | we're just looking at the whole If we're looking just at you |
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| 74:29 | Right. Right. So, this simply a graph showing you what's happening |
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| 74:35 | time. When you look at That's how you should view that |
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| 74:41 | Man, it just scares me to these analogies now because you guys are |
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| 74:45 | mean not you particularly but your generation very sensitive and action potentials like |
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| 74:52 | I was gonna see if I can him spit up his water. Either |
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| 74:58 | are or you aren't. There is in between. There is no gray |
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| 75:02 | actually had a person try to argue me in class once I did |
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| 75:05 | I'm like, no, no, , no, no. We're not |
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| 75:07 | that today, but it is so virginity. There is a strict |
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| 75:11 | of what that means. Right? is no no gray area. You |
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| 75:16 | or you aren't. And an action is the same way. Either you |
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| 75:20 | an action potential or you don't. an all or none response. There |
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| 75:24 | no in between. There's no I'm of an action potential. All |
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| 75:30 | It is You are an action potential you aren't. Okay, so, |
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| 75:36 | the key thing. Greater potential. the other hand, there a little |
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| 75:38 | easier. Alright, great potentials have magnitudes. They have varying lengths of |
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| 75:44 | . They have varying durations all dependent the amount of stimulus. Alright, |
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| 75:49 | , you can think of it like if I have a very small |
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| 75:51 | I'm gonna have a very small graded . All right. If I have |
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| 75:55 | strong stimulus, I'm gonna get a greater potential. If I have a |
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| 76:00 | but small stimulus, I'm gonna get . But very small potential. |
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| 76:04 | So, there's a direct correlation between or duration and magnitude, which is |
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| 76:11 | . Alright, That's what these little graphs are trying to show you. |
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| 76:16 | , whenever you see this, this this is a state where you're |
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| 76:20 | And then all these things down these different colors are state that are |
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| 76:23 | and saying, look, I'm off then I have this week things. |
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| 76:26 | , here's my membrane potential. I a stronger one. Here's a |
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| 76:30 | And you can see here, I've two different types. These are negative |
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| 76:35 | these are positive. So these are polarizing. These are deep polarizing. |
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| 76:40 | greater potentials can go in either Which way did the action potentials |
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| 76:45 | They're all d polarizing. Alright, , the stronger the triggering event, |
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| 76:53 | more the channels that we're gonna All right, So, basically we're |
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| 76:57 | channels were allowing ions to pass through change in membrane potential reflects a passage |
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| 77:02 | ions into the cell or out of cell. And so the longer or |
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| 77:07 | stronger the trigger, the bigger the as a result of opening more channels |
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| 77:12 | opening channels longer. That's the duration graded potentials you saw when I propagated |
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| 77:20 | action potential potential went all the way the room. So once I propagate |
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| 77:24 | action potential it will go right and keep going until there's nothing to get |
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| 77:29 | and we're gonna look at it to it on on thursday with greater |
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| 77:34 | It's like dropping a rock into a pond. Alright. It goes in |
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| 77:39 | direction from the site of stimulation. that's what you're seeing here is going |
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| 77:43 | for everything. And then as that moves away from that site, remember |
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| 77:47 | like open the gate so that person sad sack sitting there looking at across |
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| 77:51 | way at its opposite charge goes in finds its couple right it matches |
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| 77:58 | So that means the next one has travel further. And so what you're |
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| 78:02 | though is you're not getting the same in terms of the wave, The |
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| 78:05 | gets weaker and weaker and weaker and as more ions are meeting their |
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| 78:10 | So that little red line up there tells you how much free sodium you |
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| 78:14 | . So as you're going further and away there's less and less free |
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| 78:18 | less free sodium. That means the of the greater potential gets smaller and |
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| 78:23 | and smaller. Which is why I to use the pond if I take |
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| 78:26 | little tiny pebble and drop it in pond I get a ripple that starts |
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| 78:29 | fairly big and then moves further and away from the side of origin and |
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| 78:33 | dies off. The difference is it to be resistance when I'm talking about |
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| 78:37 | pond here? It's because I'm getting on matching up with their pairs. |
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| 78:43 | this is a terrible way to signal it's very limited in the distance that |
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| 78:46 | can go. But we use these create action potentials. It's the greatest |
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| 78:52 | that results in the action potential. right. So we'll start there or |
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| 79:03 | this slide when we come back and gonna have to really talk fast and |
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| 79:08 | not gonna be it's gonna be like auction house. Huh. Huh. |
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| 79:15 | . So we have one more class , yeah, we have one more |
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| 79:21 | . Yeah, it's easy mode. goal kickers are actually one of the |
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| 79:26 | important people because you can't always get touchdown with people like me that hit |
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| 79:31 | goals When I was in high If it was 35 to 45 yards |
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| 79:34 | , I was automatic right 50 yards . I'm like 75% out there that |
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| 79:41 | gonna get to like and I know , but in terms of, I |
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| 79:44 | , there's there's a reason it's called teams. It's not regular play. |
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| 79:49 | technically quarterback could be on the field the entire time. Right? Well |
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| 79:55 | the exception of the kickoff team or punt return. As long as it's |
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| 80:00 | quarterback could be there. What what , what can the quarterback on a |
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| 80:04 | unless he's older? He's the right? And that's that's that's fairly |
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| 80:09 | the case, right? A lot times, like when I hit a |
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| 80:12 | winning field |
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