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00:01 Hello? Yeah. All right, morning thursday. It's almost the weekend

00:08 some of you. If this is only class on thursday and you have

00:11 on friday, it's the weekend in hour and a half. We have

00:16 test. When next thursday do you here to take the test?

00:22 Where do you go casa? If you've never taken a test at

00:28 ever, ever in your life, you need to do is you need

00:30 go over the cost of which The Garrison Jim is the only

00:33 So Garrison gym, which is right the street over here and you need

00:36 do your biometric. What's a biometric take your thumb? I think this

00:41 how they do it. They put on a thing and it's not your

00:44 thumbprint. It's just some sort of algorithm that just says this is me

00:50 then once you do that for the of your life here at the

00:52 you never have to do that All right. You're now registered.

00:55 right. But if you don't do , you have to do it at

00:58 day of the exam. And if don't get in your exam in the

01:01 10 minutes of the time that you've allotted, then they don't let you

01:04 . And it's really, really sad frustrating okay secondly, I look at

01:09 signing up for the exams, it like everyone is signing up for this

01:13 of time, which is fine. great. You get your exam

01:16 you've got the rest of the you can go to happy Hour whatever

01:19 is that you want to do. right. But just know that there

01:22 lots and lots of slots available outside this uh class time. All

01:27 So you can sign up for any those times. So if you're one

01:30 those people that want to wait till last minute because you want to stretch

01:33 out all day long, that's perfectly if you have if you have that

01:38 or that freedom to do so. once the seats are taken up in

01:42 specific slot, pacific I said pacific slot they're not available. So you

01:49 to make sure you can get what want. The second thing I want

01:53 announce is on September 21. That's Tuesday. After the exam we will

01:59 have class. Okay I've got to to a meeting um that's out of

02:03 state. So basically I'm flying out post a video lecture of some sort

02:08 you guys that you can go But you do not have to come

02:11 . You don't have to wake up on Tuesday. There's a yeah I'm

02:16 waiting for that. I have to up early because I have to fly

02:20 But but we'll be I'll be back Thursday. So the September 21.

02:25 post that on blackboard. You'll get email about it that says we're not

02:29 class on the 21st. All Instead we will have a video for

02:33 guys to watch which is basically me to another class. All right.

02:39 it's like attending but it's not sort I guess. I don't know.

02:44 understand why it sucks to be There you go. Um Let's see

02:48 there's anything else. Um Oh well . Um What we're gonna do?

02:53 Echoey try moving down a little bit today. What we're going to talk

03:00 is a little bit better. Is still echoing? Yeah it is what

03:04 is. Good enough. Good enough government work. I'll do that.

03:09 right today. What we're going to about is we're going to talk about

03:11 cells talk to each other. All now remember cells exist in groups that

03:17 called tissues is the word I'm looking . All right remember because we're kind

03:23 working our way up. We started molecules. Remember how boring that was

03:26 and we work to the cell and the cells were gonna work to

03:30 So really the next talk on Tuesday week is on tissues and then we

03:35 to the example and then we'll basically all the background information. We need

03:39 know in order to actually get into real anatomy. Yeah. Yeah.

03:43 think it's fun. It can be of boring. Whatever. All

03:49 But anyway so cells have to talk each other and so what we want

03:52 do today is we want to look how do cells talk to each

03:55 How do they communicate with each other that they can do that communal work

04:00 . All right. And it's not that. But how do they talk

04:03 other tissues in other words? How cells talk long distances to other cells

04:08 the body? Now, before we that, we had to slides left

04:12 from thursday, Tuesday, whatever the class was. All right. And

04:16 real simple. Remember what we're talking . We're talking about making proteins.

04:21 right. And when we make we can take those proteins and we

04:24 secrete them or we can put them the plasma membrane or we can sequester

04:28 way and use them inside the Like we're doing license times. And

04:32 in order to do that, that we're putting things inside these bubbles of

04:37 that we called vesicles. If we to bring something into the cell that's

04:41 big to pass through a channel. needs to come in through a

04:46 And so what we have is we this mechanism called vesicular transport and it's

04:50 I'm keeping it real simple for you . You either going in or you're

04:53 out with the vehicle if you're going , we refer to that as exocet

04:58 if you're coming into the cell using vehicle. It's called induced psychosis.

05:03 so this is what this little slide showing you. It's like look,

05:06 that bicycle with a whole bunch of that we're going to be secretive.

05:09 , you got to look for Right. And so that was made

05:12 the Golgi, Right? We got little vesicles, there's that plasma

05:17 And then what happens is is it's to be transported to a specific

05:22 Remember we have those snares that were to say this is where you go

05:25 this is where you doc. And what happens is when it opens up

05:30 those materials that we're holding our released of the cell. Alright. And

05:34 out of the extra cellular fluid. we said already that this requires energy

05:39 because to move those things and hold in place and cause and open up

05:43 going to be cost energy to do , of course. Now the button

05:47 work because they're all right. So psychosis is bringing things in and when

05:56 bring things in and there's different ways we can do this. All

05:59 And so when I was in your like years ago, right, we

06:06 one name we call the psychosis. as we've looked at these mechanisms,

06:11 learned that there are different types of and techniques that the cell uses in

06:16 to bring things in. All right again, this is going to require

06:21 input. What you're gonna do is gonna bend said look, look how

06:24 the pictures. Do you see what did there? They just switched the

06:30 the arrows around. Right. And really what we're doing is we're

06:33 look, I want to bring something out in that environment. So there

06:37 different ways that I can do Now. The first type of Figo

06:40 . Figo means to eat. So owes, you know, to go

06:44 cell mitosis. Just the process. right. So, it's led Now

06:48 makes this unique as a process is can imagine that a little bacterium and

06:54 you're doing is you're going to reach and with the cytoplasm and the plasma

07:00 is going to reach out and surround organism. So, this is what

07:04 macrophages and neutrophils do. So when get back to you in your body

07:08 they're like uh that's not supposed to there. I need to kill and

07:11 it. I'm gonna go out, gonna surround it, create a vessel

07:14 it. And that's basically be bringing the cell. Then I take that

07:18 to a list zone, chop up inside it's destroyed. It's gone.

07:23 right. But the key thing here this reaching out pork portion.

07:27 So they create these arms which are pseudo pods fake arms. And that's

07:34 you do it. So this is we bring in large particles like bacterium

07:40 destroyed cells or something. Clean up macrophages and neutrophils for the most part

07:46 , another type is pinot psychosis, refers to drinking. So they're very

07:51 , right? They said okay, we got to sell eating thing.

07:53 well here's another mechanism. It looks the cell is not taking big

07:56 it's getting small things and so we're to call it drinking, you

08:00 it's like, okay, whatever. really what this is is that the

08:05 doesn't reach out the membrane, I've to do it this way in

08:09 It's OK, so what that means that it it comes down like this

08:13 whatever happens to be in that it's very indiscriminate, doesn't matter what's

08:19 , it's just like I'm just gonna in whatever is here. And so

08:21 get this imagination the formation of the and it pinches off and whatever happens

08:26 be in that vehicle when the cell going to use or destroy or

08:31 Okay, so that would be sell the piano psychosis. Again, it's

08:36 require a little bit of energy because manipulating the membrane, the third type

08:42 is when we envision into psychosis, is what we typically think of and

08:47 , it's going to be this imagination like peanuts. I tested not reaching

08:51 the membrane comes down the difference is we have receptors. Now this picture

08:57 show this but you can imagine there scepters all inside this area. And

09:02 when those receptors get bound up by specific chemical, the thing that binds

09:06 the receptor they migrate together. And happens is is they uh if you

09:11 enough of them that causes the membrane some special mechanism that we're not gonna

09:16 into to imagine eight. And now brought a very specific material into the

09:22 through this physical. All right. say you want a specific protein.

09:26 you do is you put out that receptor you bind the receptor with that

09:31 and then all the receptors that get up group together. You get this

09:36 and now you've captured the protein that want. And then there are mechanisms

09:41 separate out that protein from the You recycled receptors. Send them back

09:46 to the surface through exocet. Oh sorry I want to just do

09:52 Right. And then now you have thing that you are wanted to

09:56 So this is a specific process. right. Now, the name of

10:01 vessel when it comes down is just in in the zone. All

10:04 I'm just gonna just challenge you If you create a vehicle that's going

10:07 go to the surface, that's going go through the process of excess

10:10 What do you think the name of vest clothes X zone C. It's

10:15 easy when you're biologists just easy So does this process of these two

10:20 kind of makes sense. All So, it's just you're going to

10:24 these things kind of pop up over over again. So, once you

10:27 the process, it's like, oh , I see what's going on

10:29 This is a generalized process of different can use to move materials back and

10:35 across the membrane that are too big pastor a channel or a carrier.

10:42 , cell signaling is simply that communication cells. All right. Um,

10:49 how they talk to each other and are different ways that we do

10:52 And really, which type of mechanism going to be spent upon? Certain

10:56 like well, how close to the , how fast you need the signal

10:59 be. Um what is the target you're intending to stimulate or talk

11:04 So, which ones you're going to ? It looks like ran out of

11:09 . Give me a sec. The part here is being prepared. The

11:19 and tons of batteries. Yeah. know, you're gonna hear all that

11:40 this on the thing because it's the system is fine. All right.

11:47 . There we go. Remember you in the front row. Which one

11:53 you watching? Orange? Something? goes, No one hears anything.

11:59 right. Now with regard to how body works. There are two ways

12:03 cells talk to each other there through communication or chemical communication 99% of the

12:09 and most of stuff where we're going talk about his chemical communication. All

12:14 . But there is electrical as All right. So, when you're

12:18 about electrical, what you're dealing with membrane potentials, which we haven't really

12:22 about. All right. That's going be like in the next unit or

12:25 two units away. When we really talking about that. And really what

12:30 is is when two cells are attached each other through a gap junction allows

12:35 electrical potential changes in other words, to flow from cell to cell to

12:39 . All right. Oftentimes what you'll in a class like this is when

12:44 say, well, neuron jews electrical . Very few of those neurons actually

12:49 electrical communication. They really use chemical and talk to each other. They

12:55 electrical signals to talk across long distances themselves. So, um and just

13:01 be clear here, you have a side of the neuron. You have

13:04 sending side of the neuron that electrical going from the receiving side to the

13:08 side. And so, neurons can very, very long. This will

13:11 more sense when we talk about Okay, so 99% of the

13:17 That's a made up number. It be 95. It could be 93

13:19 knows? It's just most of the use chemical communication. All right.

13:25 is where your psa creating a chemical of the cell Probably through process of

13:31 Asus just as an aside maybe right exercise doses. And what happens is

13:37 community to a cell that's either next or some distance away. So,

13:42 going to clarify what that actually What does it mean to be next

13:45 our or further away? All so, first type of signaling is

13:51 auto crime. Auto means self. you ever written yourself a note to

13:56 yourself of something? Okay, have you ever talked to yourself?

14:01 , when you're studying, do you to yourself? Yes, of

14:04 You repeat yourself. You know, saying things. So, cells talk

14:07 themselves and they do it for the reasons you do. It's to remind

14:12 about things or to change your behavior . Right? When you go to

14:16 grocery store, the action that you're . When you look at that

14:19 when you're talking to yourself, is change your action from forgetting to

14:25 Okay, so cells are kind of that as well. Now they're not

14:29 there. I got to remember what they're doing is they probably have

14:32 process that's going on and they're using self talk as a regulatory mechanism to

14:38 on or turn off a process. right, So, it's a self

14:43 mechanism, you secrete The Ligon Ligon the is the agent the binding agent

14:50 will then bind on the receptors on and you get some sort of different

14:55 or change in the response in the . All right. Peric rain is

15:01 of a broader term that refers to from a cell to its nearby

15:08 All right. Now, I'm going use the term here nearby because next

15:11 becomes important in just a second. right. So, once again,

15:15 have secretion of some sort of The chemical diffuses away from the cell

15:21 it will attach to cells that we to as the target cell that have

15:27 proper receptor. What this top pictures to indicate to you here is here's

15:32 group of cells with the receptors that that Liggan. Here's a group of

15:36 that have receptors but they don't bind leg in. So, the perricone

15:40 is to just the cells with the receptors. All right. So,

15:46 message goes out, but only the that have the right receptors to receive

15:50 message are going to respond to that . All right. So, we're

15:54 specific cells to get them to do . Now, here is an example

16:01 a group of cells that are being or really this cell is being innovated

16:04 that neuron. All right. you can see here at the synapse

16:09 this neuron is talking to that It's releasing a chemical and right.

16:13 that neuron those are where the receptors located. So, this is a

16:17 of perricone signaling. Synaptic signaling is form of perricone signaling. All

16:23 And talk about neurons. This is we're gonna be talking about the whole

16:27 is how neurons tell things to do . Now. There's a type of

16:34 that's Pere Crane. So, this a subclass of peregrine that's called Juckes

16:39 . All right. Just a Just a means next to So here

16:45 we're doing is there are two cells are touching each other. They're next

16:49 each other and they're talking to each by direct contact. All right.

16:56 it's not just nearby. It's not oh well I am near here.

17:01 so I'm communicating. So this is a Quran. We have to actually

17:05 in contact. The two cells need be in contact. Now, what

17:09 can do with this is we can two different types of direct signalling.

17:13 right. The bottom. I guess did it the right way.

17:16 so up here we have cell number , cell number two, Cell number

17:19 has a protein sticking out of its . That's acting as a ligand.

17:25 . No two has a protein sitting its surface. That's acting as a

17:29 when the leg in and the receptor into contact with each other. Those

17:34 cells are talking to each other. cell is telling that cell what to

17:40 . All right now, these types molecules that you typically find in these

17:44 are referred to as cell adhesion Their cams, you'll see them all

17:49 the place once you once you've seen just like, oh, that's the

17:52 time I ever seen a smart And then you turn around and they're

17:54 cars everywhere. It's like they just once you learn something, right?

18:00 so that's what these do. The to cell recognition process allows one cell

18:06 directly contact and communicate with the cell next to it. Now, as

18:11 example of electrical signalling, we can gap junctions. So these are basically

18:17 would be a cytoplasmic bridge. So cytoplasm inside this cell is in contact

18:23 the sight of plasma and that sell these gap junctions. And so what

18:27 means is very small molecules can move those two points, which means that

18:33 you have ions flowing when ion you're creating current. And so what

18:38 can have, if you change the concentrations, you can increase or decrease

18:43 rate of flow, which means you're current, which means you're changing electrical

18:49 . All right, So there's this flow and that's what the gap junctions

18:54 allowed to do now. Where do see this in the body? Cardiac

18:58 for example, they're all connected to other one by one. So what

19:02 doing is you're sitting an electrical signal cell to cell to cell to cell

19:05 cell directly, right? Some smooth works this way where you stimulate one

19:11 and then that cells stimulates the next . You know just down down the

19:16 . So this is an example. are some neurons that do this as

19:19 but they're few and far between and probably only located in the deep

19:24 All right. So this is just cream. The last type we just

19:30 of call it. We can call endocrine signaling or long distance signaling long

19:35 and easier term to use at the level. All right. And here

19:39 it is is you have a cell is responsible for producing a chemical message

19:45 message gets secreted through the process of . Oh, sis it flows out

19:49 the interstitial fluid and then gets out the plasma. It once it's in

19:53 plaza and the blood it's transport reported the body and it diffuses into different

20:00 of the body and where it comes contact to other cells that have the

20:04 receptors. Then that cell is going respond. Right? So it's a

20:09 like the perricone. The differences is distance and how it gets to where

20:12 needs to go has to travel through bloodstream. Now examples of this might

20:19 basically every hormone in your body. fact this is what the endocrine system

20:25 to communicate. So if you want think about like this. Um let's

20:31 one. That's easy. All So stress is managed through cortisol.

20:37 you don't need to know this Cortisol is produced in the adrenal

20:41 Can you see why cortisol named Because it comes from the cortex of

20:46 adrenal gland. Alright so again you're like oh so this is why.

20:51 right. So to regulate cortisol, produce a hormone in my pituitary gland

20:57 is up at the bottom of my and to regulate my pituitary gland.

21:01 is a hormone produced in the hypothalamus is a structure in my brain as

21:05 . So I got the hypothalamus communicating the pituitary gland. So it's releasing

21:10 out into the bloodstream. They go the pituitary gland. Pituitary gland produces

21:14 hormone that then travels down to the and says, hey um we need

21:18 make cortisol and so your body begins out cortisol. All right. That's

21:23 form of longest signaling. Okay, signals. Now these hormones they're going

21:30 be different types and sizes and structures we'll primarily deal with that aim

21:36 Two. I don't think we really about any of here. But when

21:39 hear the word hormone think in terms oh that's that form of communication.

21:44 can be in the forms of peptides can be in the form in the

21:48 of steroids which is a type of but we're not going to go into

21:52 ones? Which yes sir, Clarify the nervous just give me mm.

22:01 I didn't say that. That's a point. And then I'll answer your

22:03 as well. All right. there are neurons. Right?

22:08 the example I use the hypothalamus in hypothalamus. The cell that's producing that

22:13 hormone is a neuron. And so are no Euro indie Quran cells that

22:19 in this way and they don't behave the neurons that we're going to learn

22:22 a little bit later, which is a cell talking directly to another cell

22:27 this peregrine signalling. All right. that's how the when I say the

22:32 system what it's doing there are cells the nervous system that regulates other cells

22:38 this fashion. Yes, sir. hormones exclusive to a different signaling or

22:45 it be part of characters? All . So, the question is,

22:49 our hormones exclusive to the endocrine system really endocrine signaling. All right.

22:54 the answer is yes, sort All right. All right. So

22:59 is how it works. All You can put your pens and I'm

23:01 gonna test on this. All A long time ago they started discovering

23:06 hormones actually the way they discovered it really kind of cool. But we're

23:09 going to go into that. But they tested to see how this

23:12 Is I'm gonna tell you this They took a Beatle cut off its

23:15 took another beetle cut off its head then glued the two beetles together?

23:18 they recognize that the one beetle over was producing materials that made the other

23:23 body do certain things. It was there must be something in the blood

23:29 it worked. So that's how they it out. And then someone then

23:32 all the pituitary glands of about a pigs. And they were able to

23:37 the very first hormone, I so pigs are being slaughtered for food

23:42 it's like, well, what are gonna do with the brains? What

23:43 not gonna make cheese out of I guess we could they do,

23:48 . But what they did is they in the pituitary lines about this big

23:51 you can have to collect a lot them. And this is like back

23:54 the early 1900s were trying to isolate you need lots of. So,

24:01 , so, so there was a definition of hormone is something that drives

24:05 is derived in the blood are found the blood. All right. As

24:09 learn more and more and more about signaling, We started realizing some of

24:14 things we're calling hormones are not necessarily . And so the line between what

24:19 hormone is and what other signaling molecules our. That's kind of blurred.

24:24 right. So, generally speaking, this is why I say yes,

24:27 of generally speaking, what we say a hormone. That is something that

24:32 to signal in a long distance through bloodstream. So, it's an endocrine

24:37 . Yes. But are their hormones can signal in a peregrine fashion,

24:44 . But we're not gonna worry about . All right. That's that's that's

24:48 I told you put down your All right. Don't be like my

24:52 . My son came home yesterday hey, how? It's cool.

24:55 ok because 14 And that's what 14 old. Okay. What do you

25:00 do you do today, spanish and and biology, neurobiology? What'd you

25:05 today? Difference between pro carry you out? Well, what's the

25:09 Pro character? Single cell you carry or multicellular No, they're not.

25:17 . Did you listen? Right. did the teacher teach you wrong?

25:20 he just tried to argue with I'm like, come on.

25:23 I mean? So, I made watch the amoeba sisters. You can't

25:28 the amoeba sisters, But you don't to believe your dad. All

25:31 fine. So, again, blurred . All right. So, we

25:39 this horrible horrible word right up Meta tropic metal tropic. Alright.

25:46 first half comes from metabolism. Second comes from tropic. What does tropic

25:52 ? I don't know tropic means something regulates something else. All right.

25:57 doesn't mean something with an umbrella in that you get at a resort in

26:00 tropics. All right. So meta is a process a metabolic process that

26:07 something downstream. All right. And the one type of signaling.

26:13 when you receive a message, one the ways that that cell response is

26:17 this meta tropic pathway. And so is what I'm trying to show.

26:21 says. Look here, I'm going first receive the signal. That means

26:26 have to have a receptor and I to have signaling molecule that binds to

26:29 receptor. That receptor when it gets , changes its shape. Because remember

26:34 molecules change their shape, they change activity and that change in shape results

26:39 the activation of another molecule which activates molecule so on and so on and

26:43 on. All right. It's kind like a domino effect. All

26:46 Now, what we're doing through this effect is called the process of transaction

26:52 simply means changing from one form to next. And what is the thing

26:56 we're changing? We're changing an outside into an inside message. So that's

27:01 trans duck shin refers to. And , this cascade of events is basically

27:07 turn on some sort of response. , why do I need all these

27:11 proteins? Why do I have to domino effect? Why do I have

27:14 have all these steps? Well, answer is is that that one signal

27:17 not create one response. It's actually proteins that then activate other proteins.

27:24 so it kind of turns into this cascade kind of like if you do

27:29 just do one domino after the It's taking one domino that knocks it

27:32 to which knocks over four, which over eight and so on and so

27:35 and so on. So you're activating pathways that creates a much broader response

27:40 the cell that you're looking at. , It's not a 1-1, it's

27:45 one to like many. Well, just gonna say many. All right

27:50 down here, you can see I this in or in act or activate

27:54 that. Alright, often when we signal transaction we talk about turning things

28:00 . But remember sometimes there are things are already on that need to be

28:04 off. Right? So when you're a cell, when you're signaling that

28:09 you may be turning something on, you may also be turning something

28:14 And so it's easy to always thinking on terms but just remember that the

28:18 can be true as well. so meta tropic. There is a

28:23 of trans deduction where you're taking an message turning it into an inside message

28:27 creates some sort of response downstream. right. I should point out This

28:35 right here. 2nd message. So right here, when you hear the

28:39 second message, this refers to a message. So the second message or

28:44 second messenger is within somewhere within that cascade. All right. That's the

28:51 message why it's called the second This is an example of this where

28:57 dealing with phosphor relation. Now, correlation is simply taking a phosphate group

29:02 is like on a T. And stuff. And there's energy in

29:06 bond that is about that where it's . And so when phosphate is added

29:11 something or taken away, what you're is your adding or subtracting energy.

29:15 so what this system is basically saying look here, I've got my leg

29:18 here. I've got my receptor when activate this is take this molecule and

29:24 energy to it. What it's doing allowing energy to activate this system or

29:30 . In this case it's activated. going from an inactive to an active

29:33 . And so each step along this is your activating these proteins by phosphors

29:39 them. This is just an example then not this molecule right here doesn't

29:44 turn this on but it might turn else on. And this one right

29:48 is not just turning this on but might be turning something else on.

29:51 might be turning something on to turn off upstream of it. We're not

29:56 with the specifics. It's just this showing you how this cascade looks how

30:01 is trans direction. So, what have with this picture is a way

30:09 show how we change this sort of . All right. So this is

30:13 way This is a mechanism. So we have here is we have a

30:17 protein. All right. So the protein is the green thing. All

30:23 . So G proteins are typically associated receptors Those types of receptors are called

30:30 protein coupled receptors. Do you see chairman? You have to keep it

30:36 . Right. So G PCR is really associate with the G protein Now

30:40 protein has with it G. T activity. Remember when he heard of

30:45 word ace at the end of the ? What does that mean? It's

30:48 enzyme. And so it's a T Ph which means it takes GTP

30:53 is a nucleotide with a bunch of , three of them specifically which are

30:58 unstable. And what we're gonna do we're going to just bend it a

31:02 bit so that that bond breaks and the energy. And that means that

31:06 G protein uses the energy to activate else. Okay, so that's

31:13 kind of what we're looking at here in order to get this G protein

31:18 those two states, the active in inactive form. There are other proteins

31:23 interact with it in a non covalin to change the state. And so

31:30 what these two things are referring To go on an exchange factor in

31:34 gap. So what's it doing? taking the the energy molecule which is

31:40 interacting with that G protein and it's , hey um you need to move

31:47 need to replace you with the other . And that's what this thing is

31:51 . Its allowing for you to change these two states. So, when

31:56 look at these processes over here, right. This is a specific example

32:02 it's basically saying ignore what it What it's saying is that you're not

32:07 in this process. The other regulatory that allow them to move from state

32:14 state to state. All right. these cascades. These transaction pathways are

32:21 complex. There's molecules upon molecules upon that are affecting the activity of

32:29 And to give you an idea is cascade like this from binding to response

32:35 ridiculously fast. So, all the mechanisms even though they're they're they ensure

32:42 the pathways are active and working and do very very quickly now. How

32:46 are they? All right. Back the day when I was young so

32:52 ago um back when I was young I was working in the lab.

32:57 . I worked on signal transaction cascades at a hormone in what is the

33:03 . All right. So we had in a dish that we collected and

33:07 we did ask the question. My time point because I asked what is

33:11 over time. My first time point five seconds. All right. So

33:15 means I added in the hormone and immediately stopped the reaction because that's how

33:20 five seconds is. Right. And next one was 30 seconds. That

33:23 a little bit easier than a minute five minutes. Then 10 minutes than

33:28 minutes than an hour. Two four hours eight hours, 16 hours

33:33 hours to days, four days. you can see it gets kind of

33:37 at a certain point. So where I see my first response? Five

33:43 . Right. And you'd see it darker, darker, you know,

33:46 terms of the activity T5 seconds, seconds. And then when you hit

33:51 point somewhere around an hour or two and then it would kind of slowly

33:55 back down. Alright, So incredibly . Alright, molecules. And these

34:02 you get very very quick responses. you're regulating and you're making sure your

34:09 can go forward because you have molecules allow that to happen. So meta

34:17 pathways have metabolic steps that have regulatory . That's what metabolism is. And

34:24 you to turn inside signal. an outside signal into an inside signal

34:29 trans induction to get a cellular The other form of communication is what

34:36 referred to as I on a Alright, so again, tropic means

34:41 regulate something else. And now we these different words instead of metal

34:45 which refers to metabolism, we have a which refers to ions. All

34:51 . And what we're having here is basically saying we have a channel that

34:56 it opens it allows the inflow or outflow of ions. And when we

35:02 an in floor outflow of ions, have a change in current.

35:08 When ions move you have current. so what we're doing is we're creating

35:13 current to change the activity of the . All right. Now, this

35:18 a very short lived signal. It's very rapid signal. All right.

35:22 so what you're doing is if you up a channel islands flowing and close

35:25 channel, you basically created a very current that the cell can take advantage

35:33 . That's how neurons are going to communicating primarily. All right. They're

35:38 to open up channels in the cells they're talking to and the channels when

35:44 open cause electrical changes in the cells they're stimulating. All right. The

35:52 type which kind of doesn't fall into category is what we refer to as

35:57 receptor signaling. This is how your work. All right. So,

36:03 you think steroids, think estrogen think cortisol. All right. These

36:08 all different types of steroids. a steroid, it begins life as

36:16 starts off as cholesterol and it's just modified cholesterol molecule. And when we

36:21 at steroids you're gonna go, they're very similar. They don't look

36:24 lot different from each other. But they start off as a cholesterol,

36:28 means they are a lipid and lip hate water and water hates lipids

36:36 It's a mutually hating relationship. And when you have a hormone like a

36:42 outside the cell where it's mostly water says I don't want to be

36:47 And so it goes rushing in and associated with that plasma membrane. Now

36:53 adding a little extra steps here. it makes a little bit more sense

36:56 if you look at this guy wait second there's water out here. There's

36:58 in there as well. All So what happens is is once it

37:01 in that plasma membrane another molecule comes and says hey how you doing?

37:06 then it kind of hooks up with and carries it around. All

37:10 And so basically what you're gonna do you're going to move it to another

37:16 called nuclear receptor. Now, if look at that picture, you're probably

37:21 there going wait a second. That's in the nucleus. Why are you

37:24 it nuclear? Well this receptor when activated goes to the nucleus, hence

37:32 term nuclear receptor. Alright, so un activated. It's basically can be

37:38 either place, it just kind of out wherever it is. But when

37:42 hormone comes along and binds to the receptor, what it does is it

37:47 locates to the nucleus and what it do once it trans locates to the

37:53 it partners up with another nuclear receptor always work in pairs. All

37:58 And what it does that binds to D. N. A. Alright

38:03 to the promoter region of a And its job is to regulate the

38:09 of the production of the gene. that means turning the gene on or

38:13 it means turning the gene off activation and activation. We're not going

38:17 go into what it is. All . So in essence when you're using

38:22 like a steroid and a nuclear receptor mechanism, you're activating the production of

38:29 specific mrna. Which will produce a neu protein or turn off a

38:34 Now to put this in perspective so you can understand this a little bit

38:39 . We have lights in this Everyone agree. Lights how do I

38:43 off or turn on the lights there's switch. So meta tropic is like

38:47 lights in this room. I want turn on the lights and room.

38:50 go over that panel right there. the button that says on the lights

38:54 on everything to make the lights turn are already in the walls and already

38:58 the ceiling to make that happen. ? So I made a meta tropic

39:04 . I add the leg into the that's like pushing the button and then

39:08 the things in the pathway to get lights turned on the signal. The

39:11 is already there. I on a . We want to turn on the

39:17 in the room. But first we to actually make the lights.

39:21 So we're gonna make the lights, gonna put them in then we gotta

39:23 the wiring and so I've got to the wiring and I've got to do

39:26 that. That's what I on a is doing. Sorry, nuclear receptor

39:31 is doing. All it's doing is saying I want to create this

39:35 But in order for me to create response, I have to create all

39:38 things that are part of the response . Do you think that's fast or

39:43 ? Slow? Just like turning on lights in that fashion where I'd actually

39:47 to install the lights and make the and do all that stuff. It's

39:50 than just pressing the button. But types of responses are very long lived

39:58 you're actually making this stuff over So if you add in the hormone

40:04 , using the same experiment that I describing at five seconds, I'm not

40:08 to see a response at 10 I'm not going to see a response

40:12 an hour is probably when I start a response. But what will happen

40:17 is my response will last for days . So this form of signaling is

40:24 to be a long lived signal. gonna take a while to get

40:29 But it's long lived. Yes, . Yes. So so the response

40:39 . So like right, if you an inflammation let's say you have a

40:42 . Doctor gives you cortisol really give cortisone which is a form of

40:46 You rub it in. Does it away? Right away? No.

40:49 takes a little while for it to . Right. Cortisone shots, same

40:53 of thing. It goes in The inflammation takes a little bit of

40:56 for it to happen. All right they're not giving you a medicine to

41:01 with a meta tropic pathway. Usually you're doing something like that it's actually

41:07 cascade. It's basically a process of getting it from the body to where

41:11 needed to go. But once it there, once it gets there it's

41:15 really quick. Right. Yes Former Will activate all three.

41:23 they're very specific. So this is we talk about why we separate them

41:27 . All right. So there are hormones that only work on those cell

41:33 receptor in the meta tropic pathways. . Which types of hormones will do

41:38 ones that are water soluble. They penetrate or pass through the plasma

41:42 What about I wanna tropic Well I a tropic it's just a different form

41:47 signaling but you're signaling through that receptor the surface. Right? If I

41:52 back and show you where is this boy? Right. We're on the

41:56 here is the binding site. So have to be water soluble you're not

42:01 be lipid soluble lipid soluble to just of work right through the fossil lipid

42:06 layer. So a steroid which is lipid won't act out here. Can

42:13 put a time out for a Can I confuse you all? Can

42:17 confuse that question? All right. , I'm talking in absolutes, aren't

42:24 ? Right. I said absolutely water this steroid Absolutely. Through this mechanism

42:31 10 years ago, yeah, someone an estrogen receptor which would normally be

42:38 nuclear receptor actually associate the plasma So, there are mechanisms or some

42:44 do act through cell surface receptors and the whole thing up and make life

42:48 , really difficult for all of us had these nice simple patterns to do

42:53 . Now, having said that, do we need to know this

42:59 Okay, so don't let the exceptions you up. I'm not asking about

43:05 actually. I'm asking about how the works that answer your question. All

43:09 , Okay, Yes, ma'am. . So, the question is what

43:14 the promoter region? So, when were talking um uh on Tuesday about

43:21 proteins, remember we said we bind DNA from DNA. You get that

43:25 in a message and from the RNA , you get the protein.

43:28 And we said here is a gene that gene had introns and exons.

43:32 there is that picture which had the pointing like this in the big stop

43:36 the promoter region is the area where going to start transcribing the RNA.

43:42 right. And I'm not going to you that question on the test.

43:45 just used the word that confused. . So that's what it is.

43:50 the starter region. So it's basically here, what am I doing?

43:54 going to that promoter region where I'm to start transcribing that gene. And

43:59 all the machinery that's responsible for starting process are going to be kind of

44:03 in that area. Yeah. Okay. So are we are we

44:11 with signaling here? Yes, You will be going on on the

44:18 . Okay. So the question is in depth. Right. And this

44:25 ask this after class a couple So you don't stick around and

44:28 It's like the test will cover what talk about in class. All

44:34 Right. You'll be fine. Don't out. Well, I mean,

44:38 can stress how you want to, I ain't gonna help you. All

44:41 . No, don't don't don't stress . Right. What I'm trying to

44:45 is I'm trying to lay some groundwork that we can understand stuff later.

44:49 , freshman level class. I'm not to ask you to please describe all

44:52 parts of a gene. Hey, haven't talked about that. I'm not

44:57 to sit there and go here's a . Here's a pathway name all those

45:02 in the transaction cascade. You'd be , but it's the triangle and the

45:09 . There's a hexagon in there. think it's a hex of God,

45:11 not certain. Right? It's no, that's just what is

45:15 It's basically a series of molecules that for an outside signal. Turn into

45:19 inside signal. Okay, keep it freshman level class. All right.

45:26 going to move on. We're back the cell the last little bit of

45:29 self. Oh yeah. And then get to tissues on Tuesday. What's

45:39 ? Yeah. Well, I mean just it's like building blocks on top

45:43 blocks because tissues. So the question tissues harder themselves. Now, they're

45:49 they're really not. This is how get tissues. Right cells have to

45:55 . We said tissue is basically a of cells of the same kind group

45:59 . So how do we get them group together? How do we keep

46:01 from floating apart from each other. so these are the junctions between the

46:06 cells. How they hold themselves All right. So there's lots of

46:10 types Type junction junctions. Desmond zones hearings, which didn't exist when I

46:15 in college, but now they I know they probably were there.

46:19 just didn't teach us, right? the way the hemi Desmond zone,

46:22 is the thing you find in an that makes the car sound really?

46:25 , that's a hit me something another don't know. All right. This

46:31 actually a lot easier. The names let the names frighten you.

46:35 first is the Dez Mazzone's All What a Desmond zoom is is like

46:43 velcro Alright, In essence, what have here is you have this plaque

46:49 proteins. So, that's what the thing is. You have proteins that

46:54 out from the sell these are adhesion and then you have intermediate filaments that

47:01 attached to that plaque that then go throughout the inside of the cell.

47:05 what the yellow stuff of is. , you get to Desmond Zone or

47:09 get one hemi Desmond's um and another Desmond's um you jam them together.

47:13 green molecules, those adhesion molecules they to each other. And so now

47:19 two cells are attached and holding on each other. So, that means

47:22 I pull on one cell, I'm on all the cells that that cell

47:27 attached to. All right. what it does, it helps to

47:32 these tensions. And these forces. already talked about a couple days ago

47:37 torturing our younger siblings. Right? that? We talked about the indian

47:42 and why the skin doesn't come flailing your body when you get an indian

47:47 when you twist that skin. And reason is because one cell is attached

47:51 another cell which is attached to another , but not at a single point

47:55 thousands of points. And so the that you're creating on that one cell

48:00 then distributed to the other cells through intermediate filaments. All right.

48:05 this half right. Here, that be a hemi. That would be

48:08 hemi together. It's one full Desmond . So, you already understand what

48:13 hammy desmond's um is then, That's the next slide. I think

48:17 the next slide. Now, this just trying to show you the picture

48:20 what this would look like. they they've exaggerated this to to show

48:26 cause cells do not create that much in between them. All right.

48:29 , you can imagine you can see this is that Desmond Zone Desmond's um

48:33 Zone. Those little tiny filaments represent intermediate filaments. And you can see

48:38 these cells are being stretched and pulled all the other cells. Alright,

48:42 forces are being distributed along the And those filaments which are not being

48:47 are basically all going to the central aren't drawn on these things. But

48:52 forces being distributed everywhere to all those points. So, the hemi Desmond

49:00 And again, it's really easy to at this. Go I've got to

49:02 this and this and this. don't do that. All right.

49:06 biochemistry. You get to do that biochemistry. And even then they probably

49:11 you do that. That's probably more biology. But here it is.

49:14 , you can see what do we ? We have a plaque,

49:17 That's what they're trying to show you have a whole bunch of intermediate filaments

49:21 then we have a whole bunch of , you cell adhesion molecules that are

49:25 out. And what we're doing is of binding to another cell on the

49:30 side in a hemi Desmond zone. we're looking at when it's truly a

49:34 Desmond, when we called him Desmond , what we're doing is we're binding

49:38 molecules in the extra cellular matrix. what E C. M stands

49:43 Extra cellular matrix. So, there's bunch of proteins in there. And

49:47 , basically those proteins serve as anchors which the cell adhesion molecules up here

49:54 to And so now you can imagine can have a tissue that's attached to

50:00 different tissue. It's not settled to it sell to a tissue. Like

50:05 would be a connective tissue. All . And again, if I pull

50:10 that cell, it's anchored to So, it's not gonna move

50:16 That's the purpose of the hemi Desmond to anchoring it to an extra cellular

50:22 . Now, we're going to learn basement membranes in the next lecture.

50:25 , that's where that term is going come from. The adherence junction is

50:30 a Desmond zone says the name. are we doing? And when we

50:34 at adherence, we're adhering That's that's you're starting to get it right.

50:40 like this is not hard nomenclature. ? So, basically it's just a

50:47 type of Desmond uses a different type molecule. All right. And what

50:52 does is it attach is not to filaments. It uses micro filaments,

50:58 those acting filaments. All right. it doesn't have the same,

51:04 it's just tougher or more rigid type attachment. Now, we're going to

51:10 these a little bit later in. types of epithelium tight junctions are called

51:21 junctions. Why? Because they're All right. You guys in ziploc

51:28 ? All right. You buy good bags. You can put spaghetti

51:31 This is what the commercials telling At least you can put the spaghetti

51:34 in the bag, seal the turn it upside down and shake it

51:37 it will not allow the spaghetti sauce come out. If you go by

51:41 the bags, I no one knows all he is. Okay,

51:45 You know, now that it's oh yeah, okay, lesser

51:48 definitely gonna fall apart. Probably doesn't seal. Turn that back upside

51:52 sped Getty's coming out right? Or spaghetti sauce. So, a tight

51:59 is like that. Seal on a bag. One cell has proteins.

52:03 cell has proteins. They come They attach. And what they do

52:07 they create a barrier in between the . All right. So, what

52:13 now have done is not just linked cells together. But what you've done

52:18 you've created a unique environment up here an environment that's separated from an environment

52:22 here. Okay. Which means now you have is you define different sides

52:30 the cell. So, I have picture of this. Yes, I

52:35 . All right. Think Yeah. slide different picture. So, what

52:42 looking at here, this is a of epithelium. And what we're doing

52:47 is we can see here the tight , Right. And so you can

52:51 I'm preventing things from going in between cells. And so, what I've

52:55 is I've created a unique environment down in a unique environment up there.

53:00 created polarity with regard to these So now, what I have is

53:07 side that faces outward. That would called the a pickle side will come

53:13 and do this again. When we about epithelium and a pickle side where

53:17 gonna be secreted materials and bringing materials the cell absorbing materials. And then

53:23 created a side that's usually attached to basement membrane where secretion is not

53:29 All right. We may have stuff sent out, but it's not actual

53:34 . So, we refer to this the basil side. And since the

53:38 sides are very similar, we just to the whole regions below the area

53:44 the tight junction as the basil lateral . All right. Now, what's

53:50 is that these tight junctions are not merely at the at the outside.

53:56 . They do create that barry but also proteins that associate with them on

54:00 inside. So on the inside of cell that tight junction serves as a

54:06 for that basil. Sorry, a and that basil lateral side. So

54:11 creates this polarity so that we always the cell always knows this is the

54:15 I secrete to. This is the I absorbed to. This is the

54:18 that I don't do those things. things are directed towards the ethical side

54:24 secretion and brought in from during All right. So that's what this

54:30 statement refers to. It ensures directional of materials through the cell. All

54:39 . So while it does create this , it also does things inside the

54:43 as well. Let me back up I want to this thing restrict the

54:51 membrane proteins. So, this side different from that side because the membrane

54:55 are there and they can't wander They're just stuck on one side or

54:59 other. That's what that refers Here's the gap junction. Gap junctions

55:04 for two cells that are next to other to communicate. Have direct

55:08 So you can see here these little right here are called connection molecules.

55:13 form what is called a connection C N vs O N. And then

55:20 on on one side and connects on other side come together and that creates

55:24 actual gap junction. All right. they basically allow for the flow of

55:31 small molecules and ions to pass through in between. So it allows for

55:36 cell to cell communication. Finally the cellular matrix. Okay here you can

55:49 the plasma membrane, this is the of the cell. You can see

55:54 have some protein sticking through. We some sugar sticking out as well.

55:59 that's your Glick. Okay Alex remember said there would be like okay Alex

56:03 down here. This would be side skeleton. And what we're doing with

56:06 next cellular matrix are all the proteins fibers and other materials that are not

56:12 of the cell but are out there that environment next to or near the

56:16 . Hence it's a matrix because it's bunch of different things. You can

56:20 to it and hold it near to to the um near to the

56:26 Did anyone watch the video, the life video a couple of you.

56:31 I think there's a scene in that you can kind of see the extra

56:34 matrix where it shows these receptors poking through it. I don't know if

56:40 mean you probably have to go back see if that's actually true because there's

56:43 of these videos and one of them one doesn't and I can't remember which

56:46 I gave you all but you can of see oh yeah, there's stuff

56:50 here. It's just not It's not naked plain of lipids with a couple

56:55 sugars and a couple of proteins sticking . There's this this vast network of

57:01 that sit outside. All right. you connect to them and hold it

57:05 place. And so it's kind of way to ensure that your cells are

57:13 . And it's also way to allow signaling to occur. So this is

57:17 of your environment that's allowing you to with it. That's when integrate is

57:22 a form of cell adhesion molecule. is just trying to show you,

57:26 , there's integrates. Cat hearings is one. So and so forth.

57:30 right. So, the proteins and found near but are not part of

57:37 plasma membrane. All right. But not part of horrible, horrible

57:46 . All right. So, you a life off as a single

57:52 are you single cell now? So, that means those cells must

57:56 done something. They had to reproduce over and over again. They also

58:00 along the process. And many of cells are constantly replacing themselves. Your

58:05 for example, your cells are very actually all yourselves are very much

58:10 But they're constantly replacing themselves. You're the dust in your house is basically

58:15 skin cells falling off your body and the people you live with you.

58:22 . And you're breathing them in and sticking in your lungs. You oh

58:29 gets worse. They're a little tiny living all over your you guys know

58:33 brown peanuts. Right? What's the of the guy that has dirt cloud

58:38 them? Pigpen, Pigpen, you're Pigpen. You have a cloud of

58:46 that surrounds your body. Yeah. know this is part of your

58:51 We always talk about the microbiome being bacteria in your guts. Yeah that's

58:57 . But you also have this cloud nebula. So it's a nebula.

59:01 , it's just nebulous cloud of bacteria surround you every time you get close

59:05 somebody, everyone kind of exchanges some . It's like hey how you

59:11 You know some bacteria stick around some you know? It's Yeah. The

59:18 is a dirty, dirty place. we actually have more bacteria in our

59:24 by number than actual cells in our . Yeah. And you can't wash

59:31 off. All right. So why I bring this up? All

59:36 So your cells go through this process division. So there's a cell

59:41 All right. Now this is not where I'm gonna brutally beat you up

59:44 cells. You may see one question the desk. All right. So

59:48 cell cycle has two different phases to . There's a phase of existing and

59:54 and doing stuff like that and then a phase of division. All

59:59 So the growing phase is the interphase . It's basically where you where you

60:05 stuff And so that's the G The S and the G two.

60:08 is G one stand for growth phase or gap phase one? I prefer

60:15 S face. I'm going to synthesize so that I can divide. All

60:21 . So, I'm looking at my and I'm like, okay, time

60:24 replicate that. That's what the That's what the S. Phase is

60:28 the G. Two phase is the phase to go into the division

60:34 All right. That's what G. . That's the gap faith.

60:37 it's a check some basically what it is checks to make sure everything is

60:41 , everything is ready to go so you can go and do division because

60:44 you're not ready to go, you're to screw things up. Your cells

60:47 going to be on. Not ready divide, bad things will happen.

60:51 have to destroy the cell. that's why you need the G

60:54 All right, So, interphase is one S and G two now over

60:59 on the side. You see this pit stop, Good stuff. Some

61:05 know cars. Alright, pit All right. So, I don't

61:09 why they put pit stop over but jeez here, that's the G

61:12 phase. It's basically the Oh, not going through the cell cycle right

61:16 . I really need to focus on face. Uh huh. Mhm.

61:23 is. It's just sitting over I'm just going to do my

61:26 All right. And then when it's I can re enter in and then

61:30 through G. One S. Two. All right. So it's

61:33 of a set aside. I'm not of the division part yet. I

61:37 to do other stuff for right All right. The might attack phase

61:41 in phase that's the actual cell All right. And I'm just double

61:46 I guess I do talk about look actually defined all this stuff.

61:52 So there it is. That's that's I just told you all about.

61:55 ? Built in stop signals. Make everything's okay. So when we deal

62:00 mitosis this is basically the division There's actually two parts to mitosis,

62:06 ? We tend to think of the . N. A. Dividing

62:08 But there's two things we have to the D. N. A equally

62:12 two daughter cells. But we have do the same thing with the

62:15 Alright, so with regard to division the nucleus and nuclear material, the

62:22 therefore basic phases profane met face to to face these United Great, am

62:28 going to ask you what each of things do, nope. Don't

62:31 All right. Just know because the is is if you go and take

62:35 cell and freeze it and say all , what does that sell in?

62:40 nine times out of 10. You're well it's kinda looks like profile could

62:43 in a face. All right now are world experts who do this

62:47 Right? So part of my getting degrees I had to learn form

62:53 the different phases of pro phase and are different phases of pro phase.

62:58 know it's like Prilep Putin leaped Augustine. If you've ever heard of

63:02 terms, it's a pack of the one. I kind of think there

63:06 a second you don't use it, lose it. All right. So

63:10 like oh well you can kind of stuff. But for you guys we're

63:14 looking in a microscope. We don't whether the D. N.

63:17 Is convincing at this point or whether lining up at the you know the

63:21 topic plate, all that stuff. understand there are four stages that allow

63:26 the D. N. A. line so that it can be divided

63:29 the two daughter cells and then in latter phases of mitosis this is what

63:34 going to also divide up the That process is called psychokinesis.

63:40 psychokinesis. All right. Side. sell kinesis movement. And so this

63:45 how you take a cell and clone . All right. That's what the

63:50 daughters are. They're basically clones of parents. All right. And this

63:54 how 99.9% of your cells behave? don't think I talked about. Still

64:02 here's psychokinesis and its definition basically. see psychokinesis there. I'm splitting the

64:08 is all in half. This is last slide. We are done.

64:16 my goodness. Don't let me see I can keep you here longer.

64:20 me answer questions. And you guys out of here. Yeah. All

64:25 , hold on cloud guys. so when would cells die?

64:31 So the question is, when is cell gonna die? Well, when

64:34 tell it to, I mean, all honesty, that's that's part of

64:38 signaling. So, for example, right. How many of you guys

64:41 webbed fingers or toes, anybody? . Right now, during development you

64:49 . You had webbed fingers and There were extra cells your body didn't

64:53 . So, what does your body ? It goes and tells it go

64:57 diet. So, what happens is cells in between die off. All

65:03 . So, cells don't naturally die the sense like they have a

65:07 Their signal to behave in a fashion they're actually killing themselves off or if

65:12 get damaged, then they are either themselves to die or something else will

65:18 them the signal to die kind Cool. Huh? Anybody else going

65:24 ? What do we have a test we have a test? Do you

65:28 to be here? Good. What on the 21st? No class?

65:34 going to be on video. All . You guys have a great

65:37 enjoy you have on

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