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BIOL 3324 Human Physiology - BIOL3324_Lecture26
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00:00 That would be awesome. All so this is our last class,
00:03 I'm sure all of you are very that two semesters finally over.
00:08 what we're gonna do is we're gonna about the process of reproduction, and
00:12 I like to say, this is sex talk, but it really isn't
00:15 lot about sex. It's a lot , actually, how do we create
00:20 ? And so it's not about the it's about what's occurring, uh,
00:25 a result of population. And so before we begin, we actually have
00:30 get to the point of population. we need to understand that there is
00:33 is called a sexual response cycle. you're all familiar with this. If
00:37 ever been aroused, you've been engaged the sexual response cycle. And so
00:42 refers to the anatomical as well as events that are the result of stimulating
00:48 reproductive organs. So this includes both stimulation as well as mental stimulation.
00:55 there's actually quite a broad area in they causes arousal. We're not gonna
01:02 through all that stuff. I just to understand it's not just the physical
01:06 . There's there's more to it than . And so there are four
01:11 Both sexes share the exact same all right, And so you can
01:15 here it starts with excitement, plateau and resolution. And so what happens
01:21 you progress through them and you So the idea is that, you
01:25 , there might be flirting as excitement leads to actual physical responsiveness through plateau
01:31 . Happen happens to be longer And at the end of plateau,
01:35 when orgasm occurs, and then orgasm into resolution. And so what's interesting
01:42 that if you don't have the you know this All right. If
01:44 don't have the right stimulus, then , you don't get to proceed.
01:48 basically fall back so you can move and backwards in these phases. With
01:52 exception of once you reach orgasm, you progress in the resolution and then
01:58 . That's one of two things can in females. Resolution can will lead
02:04 right back into plateau, and it bring you back to orgasm. You
02:07 actually repeat that cycle, uh, . At least that's how it's been
02:13 is that it's indefinite men on the hand, have what is called a
02:17 period. And so refractory. Period's says, Wait, you know
02:22 We're not gonna allow you to maintain . We're gonna go through resolution,
02:27 that's going to take you all the to the beginning, and that's going
02:30 prevent you from having orgasm again for period of time And what that period
02:35 time is dependent upon your age and amount of stimulation, and it actually
02:42 has an effect on the results of . So, for example, men
02:48 produce about enough semen or really Sperm have about two orgasms a
02:54 And so for each orgasm, the actually holds back how much sperm it's
03:00 releasing during an ejaculate. And so actually less semen as well as less
03:05 that's being done per ejaculate, similarly not similar, but also each subsequent
03:11 results in less pleasure and actually becomes and more painful. And females.
03:16 not entirely true. In fact, orgasm could be as pleasurable, if
03:20 more pleasurable than than the one that it. All right, so this
03:25 kind of a general view of sexual cycle and the point here being is
03:30 trying to lead to ejaculation in the . In females, orgasm does not
03:37 in ovulation. Alright or ovulation is solely on the hormones that are present
03:44 a certain part of the cycle. orgasm is kind of a bonus that
03:49 help in terms of reproduction, but not necessary for So what we're trying
03:55 get to is we're trying to get where the sperm and the egg are
03:58 . And so we've already looked at male reproductive system. We said it
04:01 really simple. Men make sperm, deliver sperm female reproductive system a little
04:05 more complex. There's, ah, plethora of things that go on.
04:09 we're just kind of leading up right . Thio, we are creating or
04:13 the of them and we are receiving sperm. But we're also releasing the
04:20 or the egg for fertilization to take . And so we're gonna serve
04:25 They're gonna serve that side of Now, we're gonna come back to
04:29 picture again because I think this is really, really cool picture. And
04:33 thing is, is that what we're at is a mouse, egg and
04:36 sperm. But the that doesn't It's It's very, very similar in
04:42 . But what I want to point here is that fertilization is the point
04:47 sexual reproduction. It's in other it's that that is the act of
04:53 these two gametes together. So we're happily, oId sperm app Lloyd over
04:58 . We bring them together. That the genetic material from the mother and
05:02 father are gonna be combined together to a new organism. And so the
05:08 that this happened, where we bring hap Lloyd, uh, pro nuclear
05:13 and they begin to mix, that's we have our new organism. And
05:18 we've basically are restoring the deployed All right, so that's that's the
05:26 thing here. That's why we get new organism. This union also results
05:31 determining the the genetic sex of the . So you're the the over will
05:37 provide an X chromosome. The male provide an X or a y.
05:42 so if it's xx your female, your x y your mail and then
05:46 other thing that this does is when fertilization takes place. We're now initiative
05:51 my topic program so that new organism begins to divide. So once you
05:56 these pro nuclear together, then you your new organism. And now you
06:00 from single celled up to cells and on and so on and so on
06:03 you become ah, for functional And that's also a relative term.
06:08 in mind. So my toasts begins a function of this fertilization event.
06:14 so there's lots of steps. All , we're gonna kind of run through
06:17 steps. So we kind of get sense of what's going on here.
06:20 this is so important. The first , one the step that's absolutely
06:26 We need to activate this firm, this is gonna make a little bit
06:28 sense in just a moment. But is a process called capacity ation.
06:32 sperm are deka pass. It stated ejaculation, and then you have to
06:37 eighth, Um, and probably the ations. Probably not correct there,
06:42 the idea is that they go through process of quiet essence and then you
06:45 to reactivate them so that they can go on and do their job of
06:51 finding for using and creating that new . Alright, now the ove Um
06:57 it's released, it's actually covered by bunch of protective layers, so you
07:00 to actually pass through. As a , you have to pass through all
07:03 protective layers. Now, even once happens, the sperm and the egg
07:07 need to be able to recognize each so the proteins on the surface of
07:11 sperm must match or must be the parts of the proteins on the on
07:16 other side. All right, on ovum. And this is one of
07:19 reasons why we have speciation is that can't If two things air diverged enough
07:25 one another, they're not capable of of the sperm and the egg or
07:28 kept capable of recognizing one another, they're not capable of fusing. This
07:33 why you don't get like monkey human , you know, or others like
07:38 horse hybrids and stuff. The animals to be close enough together.
07:42 you know, in terms of so that their proteins on the surface
07:46 the family of them are are capable recognizing one of them. Once this
07:52 , once you're able to recognize one , then the member infuse. That
07:56 when you say the race has been , all additional sperm are blocked.
08:01 once this happens, and once this nuclear enters into the the oath
08:07 then we're going to finish up that of my oasis to remember we started
08:12 at Avi election, but we didn't it. This is when we complete
08:17 and it's from here where we're gonna the last little bit of DNA.
08:20 then finally, what we're gonna do we're gonna bring those and I'm gonna
08:23 these pro nuclei, not nuclei. it's pro nuclei are fused together,
08:29 it's at this point when you get new organism. So let's kinda walk
08:35 these steps. All right, so kind of the overview of what we're
08:38 at here. Alright, So capacity simply is getting the sperm already
08:45 uh, or being not getting this ready, but getting them ready to
08:50 fertilize the open. All right, the first step is you have to
08:55 the fertilization process that began in the So remember we said we win the
09:00 . We have the sperm that can't recognize eggs. That's sperm goes into
09:04 epidemics. You get some modifications and then you go into the female
09:09 track after ejaculation. And then you swimming like man. Well,
09:14 first you're stuck on the vaginal wall then once that breaks down, you
09:18 swimming as fast you can and you work your way up into the over
09:22 . And at this point, that's before female reproductive track actually sends a
09:26 , says, you know what? guys go ahead and just wait because
09:30 not quite ready for you yet, in a couple of days, maybe
09:33 wake you up and when I wake up, then you can come and
09:36 the over. So I want this be really, really clear. You
09:41 the idea here that men are those arbiters of reproduction? You know this
09:47 that all they do is deliver sperm that sperm is just hunting and
09:51 It's not That's not true. The reproductive tract plays a very active role
09:58 providing the sperm to the ove. when it's time, All right.
10:03 other words, reproductive tracts are designed reproduce. And so, ladies,
10:08 now, you might be thinking I'm interested in I'm not interested in getting
10:12 . That's in the brain, but body at certain times of the month
10:16 sitting there going, You know It's time to get pregnant. And
10:19 gonna make you behave in ways that normally how you behave, all
10:24 And the reproductive tract saying, you what? I'm in the mood to
10:26 pregnant right now. I've done all things I'm supposed to do. I'm
10:30 to the hormones. And so what gonna do is I'm gonna start activating
10:35 when it's time to get pregnant. so this is kind of a fun
10:39 fact right here. I love showing number because you've probably been taught by
10:43 coach in high school, you know how hard it is to get pregnant
10:46 when how long? Sperm laugh. favorite one was a couple of years
10:49 . A student asked me a question honestly, I think it was a
10:52 question. And so is it true sperm die on contact with the
10:57 and it's a little taken aback by , because it's like, Well,
10:59 know, does that really make sense you? Given that, you
11:03 ejaculation, even in the vagina is to the air, So the answer
11:09 no. But But the idea here , you know, sperm have a
11:16 a long lifespan. I mean, days for a really a cell that
11:21 a cell is pretty impressive. And this kind of gives you a sense
11:26 you know, this idea that sperm be hanging around in a quiet since
11:32 for about five days should kind of a little of you guys think a
11:36 bit harder about protection, All because it's the female reproductive tract that
11:42 , Hey, you know what? time to activate you. That's what
11:45 trying to get here. There's activation takes place. All right.
11:48 activation is not just mail. It's just female, remember? Takes two
11:53 tango here. All right, So happens here is that the materials that
11:58 being produced in the female their job to destabilize the akra zone, all
12:04 ? And what that means is is we have this this this akra zone
12:08 gonna be used to help penetrate through multiple layers of cells that I just
12:13 . And so what we're doing is actually putting. It's like it's like
12:16 something on edge, like it's like ing the bomb so that the bomb
12:20 explode. And so this is one the things that's doing. It's making
12:24 akra zone capable of reacting when it into contact. But the other thing
12:30 it does, it also helps to them up. So the secretions and
12:34 female reproductive track helped to put the to sleep. And while the prostate
12:39 has materials in it, that helped help that function occur. It's when
12:46 get into that reproductive tract where you that out, and all of a
12:50 it's like, all right, let's him up. And there are also
12:54 specific signals that are going to occur well, and this is what they're
12:58 to show you right here. There's There's a hormone that helps to guide
13:03 sperm toe where that needs to That's actually progesterone, and now they
13:07 hyperactive, and that's gonna be secretion in the female reproductive tract.
13:14 if you don't have capacity ation, it. You are not gonna be
13:17 to interact with the of them. why? Because the key thing here
13:20 that deep stabilization, right? If akra zone can't destabilize when it comes
13:27 contact with the zona pellucida, then not gonna be able to penetrate the
13:31 pellucida to get to the over. the process of capacity ation is absolutely
13:36 for reproduction to occur. Yeah, is also a little fun one.
13:43 , now these values down here one don't memorize them to I don't
13:47 how accurate there, but it's a of funnel little chart. Alright,
13:50 it kind of gives you a sense look all right. When when a
13:54 ejaculated right, What happens? you know, you can imagine 100%
13:59 the sperm is deposited in the Right? So there you go.
14:03 100% right. And then let's how long does it take to where
14:07 sight of fertilization is? The side fertilization is up here in the AM
14:11 of the uterine tube or what is the ova duck. All right.
14:15 so sperm basically has thio work its through the cervical canal up the wall
14:19 the uterus through the over duct, is not a simple tube when you
14:24 down and it does not look like , okay? It's not a
14:28 it's basically amazed. So if you at it like this, what you'd
14:32 is it looks mawr like this, right? And there's nooks and crannies
14:39 all sorts of stuff. And so are not just swimming along in a
14:44 . They're basically working along a wall may or may not lead them directly
14:48 where they need to go. All , But look, look how long
14:52 takes to get to the site of again. This is a rough
14:55 About 30 minutes or so, but speaking, what happens is is that
15:00 quiet since state? Let's see, am I looking for? Racing is
15:05 occur in here, so I put sperm basically to sleep in there,
15:09 then what I'm gonna do is I'm slowly wake them up and I'm gonna
15:14 creating waves of sperm that I'm gonna moving towards the AM pula when the
15:19 , um is found in the All right, now again, consider
15:26 much sperm is actually being deposited on . Ejaculate is around 200 million
15:33 All right, Now that sperm is be first deposit in the vagina had
15:38 but even withdraw causes some to leak , actually, good percentage of it
15:42 leak out. Some of them died the acidic environment. Some can't swim
15:46 they're just bad sperm, and they know where they're actually going. They
15:50 go up the right over duck. can go up the leftover duck.
15:53 don't know where they're going, They're moving forward. And then once
15:57 how do we help the sperm get they need to go? Well,
16:01 female reproductive tract is your friend or , depending on whether or not you
16:06 to get pregnant. All right. the Miami tree, um, of
16:09 uterus and the Miami trim of the duck as well as other,
16:15 muscle is going to go through the of reverse parasol tick contraction. What
16:21 does Is it helps to paul the up the walls of the uterus and
16:27 the over ducks. And then the reverse Paris started Contractions. Pull
16:32 sperm into the over ducks, so kind of like riding a wave back
16:37 the beach. It just speeds up process, all right, And then
16:42 cumulus cells remember we had our oh , and then surrounding were a whole
16:47 of cells. Those were, granular , that were populated with it called
16:51 cells, and they secrete that progesterone the progesterone, which I showed you
16:56 here. So there's our little That progesterone is used as a signaling
17:02 to bind to receptors on the sperm help attract the sperm. In other
17:06 , there's a chemo tactic factor progesterone is drawing the sperm to the
17:13 All right, so while yes, are losing some sperm in the wrong
17:19 , once you get in the over , you know which way to
17:21 You're not gonna be just kind of going places, all right? You're
17:25 to get where that's oh side is it's telling you where it iss.
17:30 that's that long journey. Um, you go on YouTube, I bet
17:37 is a thing there, so you have to go watch this. Just
17:40 find it humorous. When I was high school, there was a performance
17:43 . Her name is Laurie Anderson, I'll never forget this. She did
17:46 performance on Saturday Night Live as the musician or whatever that one time.
17:51 she has a performance piece, a called Mach 20. So M.
17:57 . C H 20 and what it . It describes the journey of sperm
18:03 the vagina to the oath side. what she's trying to show you is
18:08 relative speed at which sperm travel. so she's saying, Imagine of sperm
18:13 the size of a whale, and left the west coast of the United
18:17 to arrive in Japan. And if wanna go watch it, I'm sure
18:22 there. It's Laurie Anderson, Mach . It takes about three minutes.
18:25 kind of funny, but that was of the very first things that kind
18:29 comes to my mind is that this journey right here is not very
18:35 you know. But for sperm, incredibly long. So what we're looking
18:42 in this picture. And then I'll after this and you can ask some
18:46 if you have it. So if have any questions, start typing them
18:49 the chat. All right, if you can imagine what we're looking at
18:55 , this is the cumulus Oocyte All right, so this is the
19:00 site, and so you can see here this darker thing represents the oath
19:06 . Alright? I kind of got off the edge right there. But
19:08 right like that. All right. then on the outer edge of
19:11 that is what is called the Zona . And then out here, these
19:15 the cumulus cells. And so all stuff is that barrier. And what
19:20 can't see is there's also this mesh of glycoprotein that kind of holds everything
19:25 that's slowly falling apart. And so strands are kind of coming out like
19:30 . They're creating this mess, work kind of surrounds the whole thing.
19:33 you can kind of see here is sales falling apart with that mess
19:38 And so this entire structure has a of about 24 hours. All
19:44 so the oversight lives here about 24 . Sperm can survive in the reproductive
19:49 for five hours, so you can of understand why the female reproductive track
19:53 of holds on the sperm until it's . Alright, if it's trying to
19:58 the goal of pregnancy, All now this this bunch of cumulus cells
20:04 the outside with that matrix of proteins collectively referred to the Corona radio.
20:10 ? Because it's radiating away like a . Alright, so that's kind of
20:15 is done, all right? And so underlying that is this network of
20:21 called the Zona Pellucida, All And it's this that we have to
20:26 . If you're one of these little sperm you need to whittle your way
20:32 and then work your way, break way through that zona pellucida in order
20:36 come into contact with that other All right? And so I'm gonna
20:41 . Therefore, second could have been for 30 minutes, and I'm going
20:45 try to find why, if there's questions so far, I'm not seeing
20:56 . So this all makes perfect sense every okay, so I'm gonna ask
21:05 . I'll just move forward and we take a look here. All
21:08 so what are we trying to All right, So for fertilization
21:12 we have to break through that Corona . Now, what happens is is
21:16 that tail that's that hyper activation in to the progesterone, hyper activation helps
21:22 direct the sperm to where that outside . And then once it comes into
21:27 , it works its way through those and in a tail helps to break
21:32 and guide itself in between the cells the like. Approach once that AC
21:38 comes into contact with the zona we have what is called the AC
21:43 reaction. All right, so we we have a destabilized akra zone.
21:48 so when it comes into contact and that akra zone or recognize that zona
21:54 that allows all these enzymes to be that allows for the sperm head start
22:02 it down and penetrating through again, tail helps to move and push that
22:09 sperm through it once it passes And this is where the artist doesn't
22:14 a good job that sperm will go this little tiny spell, this little
22:19 space. It's called the pre vital space, and what I'll do is
22:23 lie on its side and along the piece right there. So I'm just
22:28 to circle the mid piece. there are receptors that allow it to
22:34 the plasma membrane. And when those recognize the plasma membrane proteins, that's
22:41 we're going to get fusion. And is what this picture is trying to
22:43 you is the fusion, and this going to create a Siris of reactions
22:48 prevent further invasion by any other Alright, it's going to allow for
22:55 two pro nuclei to come together and that might Arctic process the basically the
23:04 step that we think so when we we're blocking further sperm, this is
23:08 is called the blocked Apollo sperm That's it's kind of its title,
23:12 right, And so, just so you understand, Polly Sperm E is
23:16 when two or more sperm nuclei enter another side and this is not a
23:22 thing, remember, you have two of chromosomes. You have one set
23:25 chromosomes from mom, right remember right? And we have one set
23:32 chromosomes from that, right? If have throwing another set of chromosomes for
23:36 sperm, that is not a good . So we want to ensure that
23:42 doesn't happen. Okay, We just what comes from Mom. That's on
23:47 other side. What comes from From the single sperm? All
23:51 So what happens is is this larger called the block policy firm in the
23:57 step is simply allowing for a change the surface of the zona pellucida.
24:06 , so the changes done a It basically causes a rearrangement of all
24:09 proteins, so you can imagine they . I'm just making up a
24:14 Let's say they refuse this way. happens is that the blocked Apollo sperm
24:18 results in a changing those proteins so there look differently. And so when
24:24 look different, they can't be bound the akra zone. That's the first
24:30 . And the second thing that happens is Okay, well, maybe two
24:33 them are gonna get in. what happens is you get this change
24:37 the plasma membrane. Basically, when sperm and the oath site come
24:43 It basically causes all the recognition proteins the surface of the oath site to
24:48 removed. And so once they're no other sperm can interact with the
24:52 side. And this is a result basically the opening up these calcium
24:58 And so what we see, we this massive influx of calcium which causes
25:03 these changes to occur. All so this serves as the signal to
25:09 this and to cause that now, last little step is that remember,
25:20 sitting with the pro nucleus in the . That is still one end times
25:27 right? Are pro nucleus in the is one end. All right,
25:32 two things can't fuse together, So have to do this. We have
25:36 make a one end plus. Plus a polar body. All
25:42 so that's the last little step in of my my hostess. We have
25:47 trigger that second biotic division, and got extrude that extra DNA as a
25:53 body. Then once that happens, you could get fusion and that new
25:58 begins to produce its own. it's actually really cool a lot of
26:03 have been done. And so if look at an oocyte, you're going
26:06 see that is basically filled with maternal . But within a couple of minutes
26:12 fertilization, you start seeing the degradation the maternal Arna and as it gets
26:19 by the zygomatic RNA and within 24 there's no more maternal Arna, which
26:26 that's it's incredible how quickly that process place that you're basically destroying the maternal
26:32 and you're replacing it as fast you with the psychotic ones. Now,
26:37 I want to show you is e go back to that picture. So
26:40 , we're trying to get these two together, right? That's that
26:44 I'm gonna go back here and I'm take a look. If that one
26:48 I told you were going to come to I want you to take a
26:52 look at this. So this is know, you see, it's a
26:55 electron Micrografx. It's at 4700 fold and so you can see the proteins
27:02 are on the surface of the the side here. All right, but
27:08 you look carefully, look right If you see that bald spot,
27:13 a sign of male pattern baldness. , I'm kidding. That's not what
27:17 is. That actually that area right that's lacking surface proteins is a site
27:23 sits right above the pro nucleus in other side. And what what this
27:29 ? It ensures that the sperm in with the other side is gonna be
27:34 some place at some distance away from the pro nucleus is. So this
27:40 the pro nucleus an opportunity to go that second model division before fusion takes
27:48 . I think that's just kind of right, I'm back. Let's take
27:58 look to see if there's any All right, so the question that
28:02 passes, the action lies in the . Technically, it's part of the
28:07 , but it actually overlays the pro . Alright, so I'm gonna try
28:12 draw this out so that you can this a little bit better. It's
28:15 gonna be the best thing. So can imagine you have a mid
28:19 You have this pro nucleus, which basically, you know, compressed
28:23 And then on the surface of that's the AC resume. So
28:29 this thing is referred to as the . But it actually is kind of
28:33 own little structure that overlays everything you imagine. Cytoplasm is kind of like
28:41 because you want this. This is formed from the Golgi. And so
28:44 just filled with a bunch of Uh, some pro nucleus is what
28:52 by the African, Uh, no, because again, the AKRA
28:57 is there to be destroyed. The nucleus is actually wrapped by its own
29:01 is all. And if you look the picture over here a little
29:04 you can kind of see look at they set up the akra zone.
29:07 kind of set off to the It's not a great picture. I
29:10 if we go back and look at artist, they probably did a better
29:14 . Um, when you were a income, this slide to see,
29:18 didn't do as well his job You know, they kind of
29:21 Look here, cytoplasm. And the is, is that the cytoplasm kind
29:25 underlies. It kind of sits like , and this kind of sits off
29:29 the top of that. And yes, there's kind of, ah
29:34 of materials that sits on the Akron , but it kind of stands out
29:39 its own. It's like putting a on the top. So while the
29:44 sits on your head, the um, kind of sits on the
29:48 or on top of the pro It doesn't have cytoplasm on its
29:55 Kind of cool. Yeah, whole being is that you wanted to destroy
29:59 it comes into contact with. All , But if you want to think
30:05 I say, all right, the the actress, um, sits in
30:09 head. That's fine. I'm not try toe distinguish that. I'm just
30:13 trying to play with the nuance here because it's my area. All
30:19 so here we are. We've gotten sperm in our egg together. They've
30:26 their little dance. We fertilized fertilization takes place in the, um in
30:32 ampara of the over decked. Or we call the fallopian tube where the
30:36 too, And immediately once that right so you can see I'm now
30:40 I goat? That's the fancy word saying fertilizations. Take place, and
30:44 is what is now the new And so it's undergoing DNA replication undergoing
30:49 topic division. So there's multiple So we go from one cell to
30:54 cells to cells to 4428 and then get wonky. So we're now starting
30:59 see some actual, um, And so, in eight cell,
31:05 , Zygo becomes a 12 to a , sell more ula all right?
31:11 so things were coming kind of Now you're zona pellucida is still
31:16 You can see it. See how dividing inside that little tiny structure that
31:22 pellucida. And so the cells are compacted because they're being restrained by that
31:28 pellucida. And ultimately you will have hatch. I mean, that's that's
31:33 kind of laugh at that is like zone Appaloosa is this protective barrier,
31:37 eventually the Morial A is gonna have break out of that, and so
31:40 gonna happen a little bit later. the cells are getting smaller and are
31:45 compressed or compacted within the context of monopolistic. Now the uterine duct,
31:53 the uterine tube is has a layer smooth muscle in the smooth muscle stays
31:58 a contracted state, Um, for 5 to 7 days after ovulation.
32:05 right? And then after about seven and it relaxes and it becomes,
32:10 , dilated. All right, so go from a contracted state where it's
32:14 , and then you're going to Alright. And this forces the zygote
32:19 remain inside the uterine tube until the is ready for implantation. All
32:27 so it's not like you get pregnant of our fertilization immediately, you're going
32:33 . There's a timing issue, and is what's really kind of interesting.
32:36 you haven't taken developmental biology yet with Seder, I really encourage you doing
32:42 alright. Developmental biology is one of biology where you look at it and
32:46 Okay, the fact that I even is an absolute miracle, given the
32:52 of times or the number of problems can occur between the moment of fertilization
32:56 the moment of birth and in particularly in particular, the first nine days
33:02 incredible that you even exist because of the things that have to go,
33:07 , right. And so you can here that the memorial of is that
33:12 where we're trying to get so that can go to get to implantation.
33:17 right, so the moral of the Morial comes from moral. Um,
33:21 you you guys speak Spanish, it's . I think on basically means
33:28 All right, that's kind of what looks like. Blackberry, second
33:36 Now the memorial A will begin producing kind of cavity inside itself. All
33:46 , so this is kind of you imagine this is that cavity. It's
33:49 of grown, All right. And this is showing you is that the
33:57 cells are being separated. They're being . And creating this kind of interesting
34:04 which is called, uh, the assist. All right. And so
34:09 blasts is has two different types of , and so we're starting to see
34:12 real differentiation. The cells that are on the outside of this cavity is
34:18 the trophy blast. All right. this will ultimately form what is the
34:22 embryonic material of the organism. In words, will produce what is called
34:27 Korean, which will become part of placenta and and all these external structures
34:34 the organism, and then the cells air found internally. They're kind of
34:39 off to the side. This is is referred to as the embryo blast
34:43 the inner cell mass. And this what is ultimately gonna become the
34:47 All right, So this is where is really kind of separating out these
34:52 tissues, all right, The very steps. And so what's happening is
34:56 round Day five is when you start the blastocyst form from this more
35:01 All right? And then you could that over duct relaxes and that allows
35:07 blast assist to start moving towards the . Now, similar. This is
35:12 hatching stage. You know, I you it's gonna Pelosi those there,
35:16 so it kind of gives to break . And so the blast is kind
35:19 wiggles its way out of the zona and now able to come into contact
35:24 the uterus. And it's around day that the uterus date or shoes any
35:30 , seven post ovulation. So think of our uterine cycle,
35:36 We had immense seas and then we that time upped ovulation, right?
35:40 then we have that that phase, is the implantation phase, right?
35:45 project station all phase with the proliferated the project station or secretary phases.
35:51 other thing that's referred to it takes seven days after after ovulation before the
35:58 is ready for implantation. And this of implantation lasts about 48 hours.
36:04 around between day seven and day So again, I'm just gonna try
36:08 draw you the chart here. So day zero Thursday 28 a 14 is
36:16 ovulation. So you're looking at a sometime in there that you're expecting implantation
36:23 occur. And if you miss that or if you don't implant properly,
36:28 when that's when the signal from the does not go back to the corporate
36:34 and just says, basically, wipe off plane. We're starting all over
36:38 . All right, So what happens is that the blast assist finds its
36:42 into the uterus, and one of characteristics of the uterus is that the
36:47 has been growing, but it also the endometrium to get close together.
36:53 , while you're listening to me, want you to make a bowl with
36:55 hands. All right, so just you're scooping up water and you're about
36:58 sit from your hands. Okay. want you to make that. So
37:02 is what the uterus looks like All right. But now I want
37:07 to do is I want you to your hands together like you are
37:12 right? So you're basically folding your together. This is what the uterus
37:16 like during the period of time of . It's called opposition. All
37:21 And so, in essence, what doing is you're bringing the walls of
37:24 uterus close together so that this blast isn't just rolling around inside that
37:31 Instead, what is doing is that surface of that of that blast assist
37:36 come into contact with either side of uterus so that it can then find
37:42 twain implant. And so there's this of adhesion. So opposition is the
37:48 wall getting close together? Adhesion is you have interaction with the trophoblastic
37:54 the ones on the outside and that wall. All right, now,
37:59 way that our cells implants aren't sits implants. Is that the inner
38:04 mass lies closest to the uterine wall the endometrium. Not all organisms do
38:13 . So this is unique to Might, for example, do the
38:16 opposite. All right. But once adhesion takes place, you have the
38:20 proteins on the on the wall of uterus. You have the right proteins
38:25 the surface of the trophoblastic. That's to create a reaction because of the
38:30 . Start releasing enzymes and you start breaking through the epithelium. All
38:36 so you basically dissolve the epithelium. what this is trying to show
38:40 This is the turn. It refer his invasion. She start destroying the
38:44 and the cells because they're being or releasing all these nutrients and it
38:49 the blast is is to take up nutrients and the trophoblastic cells begin to
38:54 differentiating and create two different cell One population is the inner one.
39:01 so we're gonna kind of ignore This is what you see down
39:04 It's kind of what everything is. there's that's the entered inner layer.
39:08 right. But the outer layer, is what you're seeing right there.
39:12 ? I'm circling right there. Those the census Eo truffle blast. What
39:18 is is that these cells that are begin to fuse together and create this
39:25 blob like sell. All right, a census. She, um And
39:28 the one that's releasing this material, , these enzymes to break down the
39:33 wall and allowing it to invade into endometrium itself. And you can see
39:38 am I doing is we're borrowing All right, we're pushing our way
39:43 , and we're getting to where the vessels are and where the glands are
39:48 . And if I race this income slide, you can kind of see
39:51 pockets. Those little tiny pockets are , and they represent where the blood
39:57 used to be. And so now you have is you have blood vessels
40:01 are you have blood that are being in these little pockets that are being
40:07 by cells or a large blob cell belongs to the embryo. And this
40:14 how this embryo is getting. All nutrients is directly from the blood and
40:18 the glands that is beginning to break . All right, So by day
40:26 , you've already borrowed all the way . All right. Remember, we
40:29 around day seven by day nine. so the endometrium closes over and basically
40:38 the blast itself. So part of reason we have a menstrual cycle where
40:44 is immense seas is because if for reason this embryonic program fails, you
40:50 to get rid of this entire functional so that you can get rid of
40:56 defective embryo. Alright, That defective assist. All right, that's why
41:05 have this. All right, So idea here is I'm the cell bounces
41:12 , it comes into contact, it its way through, and it gets
41:15 and protected. And once it gets and protected, one of the things
41:19 it starts releasing these census show trophoblastic is it begins to produce a hormone
41:24 human chorionic gonadotropin. And it's this that serves as a signal back to
41:32 ovary to say I am here and exist, and I've implanted and everything
41:40 going hunky Dorry. HCG has the structure as, um FSH. All
41:51 . The H stands for human c chorionic. Right? So this is
41:56 the Korean right right there. There a Korean Excuse me, Not not
42:01 , That's the endometrium. And then , right? So go nado,
42:08 . And if you're paying close attention we were talking about the hormones FSH
42:14 L H R conetta trope bins. it's It's basically the same molecule.
42:21 that in a race? Mint My slide. Now this is where
42:31 going to kind of divert. So gonna ask if there's any questions.
42:34 don't see any questions. There are least didn't look like anyone asking
42:38 It's our last check, but are any questions so far about this?
42:44 you find this a little bit Like I said, I encourage you
42:48 take Dr Seders development class because we a lot about what goes on day
42:54 day for like, the first And then after that, then it's
42:58 so interesting, and then you could like way. So it's really kind
43:02 cool, and the program that's happening the genetic level is really, really
43:10 all right, with no questions. move on. So here's the
43:15 The placenta doesn't arrive until a little later. All right, But it
43:20 one of those new organs, and an interesting thing. Like I
43:22 females produced two new organs. One the placenta. One is the Corpus
43:26 . Um, and they're both endocrine , but the placenta isn't just integrate
43:30 . It's also organ of exchange between maternal and the fetal blood.
43:34 you don't actually get any mixing of blood, all right? There's actually
43:37 barrier between them. All right, down over here, you can imagine
43:41 is where the fetuses. I'm just put a little There's my little
43:45 See, there's a smile in our there any limbs, Okay. And
43:50 happens is is that that Korean begins change. All right, those since
43:55 in terms of begin to mutate. remember, they penetrated through into that
44:01 . So the placenta actually is a of those two tissues being in close
44:07 towards one another. So this right , that little line, you can
44:11 the cells kind of going up and that serves as a barrier between the
44:15 tissue and the fetal tissue. But truth is, the fetal tissue is
44:21 this right there. That will There's two of them that I'm circling
44:27 of those air referred to as Ville all right. And the ville?
44:31 belong to the fetus. The city belongs to the mother. And so
44:37 can see over here they're showing you is the maternal blood vessels and then
44:41 . I don't know if you can , but I've got neighbors who have
44:44 people using their weed eaters and It's very loud. Very frustrating.
44:50 , but what we have here is surrounding the Korean and outside this decision
44:55 we have these big giant pools of . All right, that's what this
44:59 trying to show you now. Big of blood is all maternal blood.
45:03 so what happens is the arteries bring fresh, oxygenated blood. And what
45:09 is there's a material exchange. It place across the ville. I all
45:15 ? So the fetal blood vessels, can see our there's a boundary between
45:20 blood, right? So you can it right there. Right? So
45:24 maternal blood never comes into contact with fetal blood, but it does have
45:29 perm selectively permeable barrier that allows for to be passed between them. And
45:38 three auction, native blood or the is leaves. And so you end
45:42 with the option of blood that's gonna via the things all right. And
45:46 the blood that the fetus is getting auction is traveling down the umbilicus.
45:53 is attached, um, to um, basically placenta to the fetus
45:59 basically delivers the blood to the Uh huh. So, placenta,
46:04 not gonna go and look at how develops over the course of time.
46:07 around roughly 66 months out of the months. Not entirely accurate, but
46:14 can kind of get a sense. basically the second or third trimester is
46:17 it's most prominent, all right. so not only is an organ of
46:22 , but also serves as a endocrine that is absolutely essential for producing the
46:28 for pregnancy. And speaking of here we go, I have already
46:34 HCG. It's the gonadotropin produced by sensation of travel blast. It ensures
46:41 the Corpus lieutenant does not degenerate. what is the purpose of the corporate
46:44 ? Pump out progesterone and estrogen? helps to ensure that the pregnancy is
46:50 . So this is what it's kind trying to show you here. Is
46:53 the primary regulator of pregnancy of the maintainer Pregnancy is gonna be the ovary
47:01 specifically the corporate Sluti. Um, right. And that's being driven by
47:06 HCG being produced by the, um issue triple blast cells. Alright,
47:12 progesterone maintains pregnancy. Um, estrogen , uh, suppresses g are gonna
47:21 trump in production and helps to ensure the tissues are are supporting pregnancy.
47:30 right, so what are we We're relaxing ligaments. We are helping
47:35 uterus grow. We're helping the mammary grow larger, all right. It's
47:41 true for progesterone as well. But the second trimester, notice you got
47:47 larger organism. So the ovaries aren't to support pregnancy quite as well.
47:53 the placenta takes over and starts uh, the progesterone and estrogen and
48:00 very much later on. Now it's the progesterone and estrogen that's being being
48:05 . You don't need. Why does hcg to maintain this process? There
48:12 a couple other hormones. I want to be aware of. Three in
48:15 , first is relaxing, which sounds an awesome hormone. Alright, it's
48:20 by the corpus to Tim and His job is to print up
48:25 What is the purpose of angiogenesis is make more blood vessels so that you
48:29 deliver, uh, nutrients so that can deliver hormones and signaling molecules.
48:35 this is all taking place in the . That's what it's acting is on
48:38 uterus. The placenta produces CRH. already seen, uh, cortical Tropic
48:45 on critical trope releasing hormone. It's produced in the hypothalamus, but during
48:49 , the placenta produces tons and tons this. And it appears, you
48:56 , a lot of evidence shows that job is to figure out how long
48:59 pregnancy is supposed to be and when tuition occurs. Alright, so that's
49:05 of the key one. Their scr that we have h p l human
49:10 act A gin can produce produced by placenta. It's a member of the
49:15 hormone family. Yeah, its job to favor fat metabolism for the
49:21 All right, so the idea here that you have fuel that the mother
49:26 in her body. You're gonna leave for the brain as well as for
49:30 fetus. But for to maintain the to promote the mother's life, we're
49:37 metabolize fat. All right, so the job of H. P.
49:45 Yeah. See, I got a questions here, right? Patrick is
49:53 , is it still possible? Get away from days 21? Um,
49:58 answer. That is probably no. right, now again, the question
50:04 asking is your There's kind of a bit of a nuance to it,
50:08 ? Pregnancy is a is a kind a broad term for multiple steps,
50:15 ? So fertilization occurs within 24 hours ovulation because the other side can Onley
50:22 around for 24 days. But you have population four days before ovulation and
50:28 become, uh, still get Alright, But fertilization doesn't necessarily mean
50:34 . Pregnancy Onley occurs once implantation has . And so when this plant implantation
50:41 , well, that's literally in that window for about 48 hours, about
50:46 and nine days after ovulation. So order for that to happen, the
50:50 has toe happen. You have to able to go through the entire,
50:55 , I got it programming to get more Ula and then ultimately, the
50:58 . It says the blast assist, has tow land appropriately in that window
51:04 time. Now am I saying if , you know, nine days and
51:08 hours, you know that you're out luck. No, that's it's
51:12 It's a window, and it lasts 48 hours. It's not specifically 48
51:17 zero minutes zero seconds. But the is excuse me. The problem
51:26 is that the timing for no matter long your cycle is, is really
51:32 the moment ovulation occurs. That's one encourage. You basically have 14 days
51:39 the men seats occurs, and so window is actually very kind of specific
51:45 those 79 days. So the answer your question is no but right,
51:52 you have to have a little bit leeway and not be dogmatic in terms
51:56 the actual minutes. His or ours what I'm trying to get that
52:02 I answered your question. Alright, let's talk about gestation. Notice how
52:12 just kind of jumping and we're doing broader looks at these processes gestation is
52:20 we refer to as pregnancy takes about weeks from the moment of conception conception
52:26 the moment when the sperm and the fuse and you create that Zygo.
52:31 right, Now, whenever you get , what they'll do is they'll do
52:35 really, really ridiculous mass based back based on your last men sees.
52:41 that's usually how they figure out how weeks pregnant you are. But that's
52:46 the most accurate method. Alright, there are lots of physical changes that
52:50 taking place, and most of these kind of familiar with. All
52:53 obviously, if the fetus is the uterus has to grow toe to
52:57 that. So you're going to see massive enlargement of the uterus?
53:01 the breasts are gonna enlarge, and they're doing is they're developing in such
53:06 way so that they can actually produce . All right, so we're going
53:09 see here in just a moment that are predominantly just fatty tissue with some
53:15 that air there that are rudimentary. not functional until pregnancy occurs. And
53:21 that's the changes that are gonna have happen. We're gonna take these rudimentary
53:25 were gonna make him functional. All , Now there are new nutritional requirements
53:30 result in weight gain as well as volume gains. Right. So,
53:36 , you need to provide nutrients to fetus as a mother. And so
53:42 going to actually store up fuel for and the fetus as well as,
53:48 , have enough blood and blood vessels support that new tissue you're gonna be
53:54 for Do you're gonna be eating for . You're gonna be paying for
53:57 You're gonna be pooping for two. in essence, Mom, you're now
54:02 machinery that allows that that baby to . Alright, so rest pro activity
54:10 urinary output increases. So you're, know, when you when we see
54:14 who have to pee all the time they're pregnant, there's two reasons for
54:17 . Just the pressure on the bladder the need to pee. But
54:21 you're actually producing mawr waste because you the fetus of producing ways, and
54:26 picking that up in your blood. so now you're needing to filter out
54:29 waste Aziz. Well, so, Station, 38 weeks and all these
54:34 were taking place at around 38 Sometimes it could be longer. Sometimes
54:39 could be shorter way go through the of partition. I say we that's
54:44 royal. We not the males are this on Lee. Females get to
54:48 the guys get to sit on sideline make funny breathing noises, right,
54:52 make their wives feel like they're part the the the process. So this
54:57 what is called labor and delivery. so what we're going to have to
55:00 is we're gonna need to make that canal large enough to accommodate the passage
55:04 the fetus. Alright, so everyone to make a fist, and I
55:08 you look down the front of your and that is the size of your
55:11 canal, right? That little tiny between your fingers that is the uterine
55:16 . And so you have a baby needs to get through that the size
55:19 the baby's head is about the size a naval orange, all right.
55:23 I'm not talking the crappy ones you at the dining. I'm talking about
55:27 good ones you get, Costco, about softball size alright. It's not
55:32 the size of a grapefruit, but large, right? And so what
55:37 to happen is you're gonna have to some changes to that cervix right
55:44 What's gonna happen is is at the time the uterus is gonna use that
55:47 mitri, um, to expel the . And so, while there is
55:51 for expulsion rights, in other the cervix is too small. The
55:56 trim is gonna have to get stronger stronger and stronger in order to get
55:59 fetus past. So there's two processes are taking place here. We're gonna
56:04 the cervical canal in process of and then we're also going to use
56:09 contractions to propel or push the baby . All right, now, there
56:14 some basics. Now, we're not into the deep details. So there's
56:18 that is involved in all this stuff everything, but ultimately what? We're
56:22 down to it. We're gonna get down to the production of oxytocin.
56:26 . Oxytocin is the signaling molecule that gonna put that is gonna act on
56:31 tissues to cause the release of prostaglandins prostaglandins are going to be the ones
56:38 act on the Miami atrium to cause contractions. All right, so
56:43 simple process. You know, oxytocin the primary similar. That results in
56:47 prostaglandin. The prostaglandins promote muscle contraction the mama tree. Um, but
56:53 other thing it does, it deals this problem right here. It softens
56:56 dilates the cervix. Remember, the is like your fist, right?
57:02 make that fist, look down that tiny hole. The hole is gonna
57:05 bigger, but the fist is still same size. You've got to make
57:09 fist as thin as paper. All , so something that looks like this
57:14 going to eventually have to look like , right? So there's your whole
57:18 it. We're just gonna make this big giant hole through that. All
57:22 , so that's the change that's gonna to happen. All right, So
57:27 those contractions begin, we're going to with another positive feedback loop, all
57:33 ? And in essence, what's happening is we're going to see the pressure
57:37 the cervix is going to cause a that goes up to the brain specifically
57:44 the hypothalamus causes release of oxytocin. is released, comes down acts on
57:49 Miami tramp causes the production of Prostaglandins caused greater contractions, which pushes
57:56 futures up against cervix, which caused release of a signal. For it's
58:00 signal back up to the hypothalamus Really oxytocin, which causes more,
58:06 prostaglandins, which causes greater contractions on on and on until the baby is
58:11 delivered. All right, so that's positive feedback loop. Once the baby
58:15 delivered, there's no resistance, no pressure. And so you you
58:20 kill the cycle by releasing the So labor and delivery has these two
58:26 these three basic steps to them. right, I love this picture.
58:30 gonna talk about the picture. The is a cervical dilation. All
58:34 When we think of labor, this the thing that we're primarily dealing
58:39 The last is this is like, is the Lavery labor. This is
58:43 , and this is also delivery. everyone ignores that for some reason.
58:47 ? And so when someone is going and, uh, they say that
58:51 about to deliver, they have to through this process of dilation. So
58:57 cervical Canal starts off about that size one centimeter. That's why I was
59:01 to get out. It's basically very small, but we need to
59:05 something through that that's a little bit . And so when they say that
59:09 reach tensing 10 centimeters dilated that that little circle has expanded to the
59:17 about the size of the bagel. food is a great example use
59:23 But that really kind of paints the , doesn't it? Right? So
59:27 dilate about 10 centimeters, but we thin out. So we want to
59:33 we're really, really thick, but going to go to very,
59:37 very thin. That's the effacement. so nurses, when they come in
59:43 they're checking the check every now and , what they do is they take
59:46 finger into the vagina or two fingers the vagina, and they're feeling for
59:50 crown of the head and so they run their fingers along the cervix,
59:54 if the fingers fall down to the , then you're still not effaced.
60:00 if they can run their fingers along from the cervix across the crown and
60:04 no bump you know, in what you have is you have reached
60:09 effacement and you're ready to give Alright, And dilation is they kind
60:14 estimate the size based on what they're as well. So the second
60:20 So that's number one. Number the expulsion Expulsion simply occurs after dilation
60:26 . This takes about 30 to 90 . Now my wife is super
60:30 I'm just gonna say that now we forced four kids their first set of
60:33 . We have two sets of The first set of twins were born
60:36 15 minutes. Right? And so to kind of give you a
60:40 I mean, obviously it's a lot . The second child comes in a
60:43 faster because the birth canal has been significantly. But she was able to
60:50 the first child leave her body after . Full dilation within 15 minutes.
60:56 was really impressive. All right now contractions are occurring in regular patterns and
61:04 they train you to do is to you to bear down in conjunction with
61:09 contractions to help facilitate the baby being out through the birth canal.
61:16 Once the baby has been expelled. you're You're done with this stage,
61:22 typically what they do. That's when in the hospital. They grab the
61:25 . They clip the the umbilical they go away. And do they
61:29 there at guard score? Then they the baby on the mother's chest,
61:32 everything is hunky dory. If they a good act, uh, guard
61:37 , all right, but we forget actually another stages. Well, that's
61:41 placental stage. And so there's also series of contractions to separate the placenta
61:47 the uterine wall and expel the So we usually typically referred to This
61:51 after birth. It takes about another or 30 minutes again. You're not
61:56 paying attention to that because, you , the hardest part was really right
62:01 , too, right there. That . Once you get to this
62:05 then this is piece of cake all right. And no one ever
62:09 you. Do you want to see placenta now? I worked on placenta
62:13 little bit when I was a grad , and so we we were really
62:16 when we got placenta. They would us and say we have someone who's
62:19 birth. You guys want placenta? like, Yeah, we'd run up
62:22 with a a tub and collect the . So this is kind of that
62:29 process, right? Here we You can see the cervix right there
62:35 neither dilated. Nor is it he right here. We can start seeing
62:40 . You can see a face. is a little bit flatter,
62:44 This is the delivery portion, and , ultimately, the injection of the
62:49 . It's not a great picture, you kind of get a sense of
62:51 going on. We're coming down to end. Are there any questions about
63:06 ? No problems, no question uh, part tuition. Excellent.
63:09 right, let's get down to the little bit. Both males and females
63:13 memory glands. Typically, only the have functional mammary glands. All
63:19 now I like to point this out the guys because lays, even if
63:22 guys never say we are, we're infatuated with boobs. I don't know
63:27 it's ingrained in our DNA. All , but a merry Glenn is simply
63:32 modified sweat glands. All right, , guys, that's what we lust
63:36 is a sweat gland. It's a nice wet blame, but it's a
63:40 gland nonetheless right now and the non female. We're going down download
63:46 Basically, the glandular portion of this is largely rudimentary. Alright,
63:53 It's there, but it's not all right, so the breast is
64:00 fat tissue surrounding this rudimentary glandular In a pregnant female, the glandular
64:09 undergoes modification, alright, and so becomes functional because of the signals that
64:16 receiving from the placenta as well as the hypothalamus. And so, if
64:22 look at this one girl structure, see there's about 15 to 25 lobes
64:26 can kind of see there and down . But they are. They have
64:30 that all worked their way to the the nipple. The nipple is demarcated
64:36 the al Viola. Excuse me, I said, I'll be all of
64:38 areola. The areola, basically is target. It's a bull's eye that
64:43 baby can actually focus on what All right, what holds all this
64:47 ? So you can see here is much culture of the chest. There's
64:50 ribs and so this is being held place by ligaments. Alright, so
64:57 suspense three ligaments hold the breast the underlying muscle all right, so
65:05 , that's what it looks like as lactation is concerned. This Onley occurs
65:13 gestation, all right, so after tuition, that's when women are capable
65:18 producing them. So during gestation, the estrogen. Progesterone is going to
65:24 the thing that makes the breast Ah, hormone called prolactin, produced
65:30 the hypothalamus, says, All let's make all the enzymes that we
65:35 for milk production, all right, we're still not going to produce the
65:40 . All right, so it's the of these hormones that allow us to
65:46 produce milk. Alright, so gestation develop the tissues, but it is
65:54 Lee after you lose estrogen progesterone that capable of producing milk. Production of
66:01 is called lactation as yeah takes a bit of time. Baby learns to
66:08 on within the first five days. days, five days, baby,
66:13 , already instinctually knows that a latch a nipple begin suckling, you
66:17 immediately produced milk. There's classroom, ultimately will start producing milk very
66:22 thereafter. And it's this suckling that triggers the let down reflex, which
66:29 milk production. So two hormones are here. Prolactin is easy one
66:37 Prolactin says. When I am stimulating breast tissue, I will produce
66:42 Prolactin then produces enzymes to produce Alright, so prolactin is four
66:47 That's really, really simple. As as the nurse, baby nurses and
66:51 suckling you're going to produce milk, this nice and disgusting. If you
66:56 seen the last Emperor, which talks the last emperor of China, he
67:01 a nurse made into Hiss like when was like 12 years old. And
67:06 , basically he suckled at the breast he was 12 years old.
67:10 if you don't know the last temperature emperor, you probably know grown
67:15 Which is the Chris Rock Adam um, Kevin James movie where Kevin
67:22 had a four year old child who still breast feeding. Right? So
67:27 long as you're still breastfeeding, you're producing milk. Now, milk is
67:32 ejected as a result of oxytocin You should think when I see
67:36 I think smooth muscle contraction eso the causes the smooth muscle to contract
67:46 The Al Viola impressed the milk up the ducts, which is then,
67:51 , squeezed out and into the mouth suckling. Alright. The other thing
67:58 does during this post, uh, post part of, uh,
68:05 uh, part tuition period that's not post part of his right. Probably
68:09 correct term is it promotes inv And so I want you again.
68:13 . Look at your fist, that's the size of your readers before
68:17 . And then, if you can of a basketball plus volleyball that's the
68:20 of your uterus after pregnancy, and it's gonna shrink back now within a
68:25 of days, a couple of weeks down again to the size of your
68:28 as a result of the oxytocin being . So it helps to return the
68:34 its original size. Now, as as you're suckling right and your
68:39 that's a pretty good indication, or pretty good sign that it's probably not
68:43 good idea to get pregnant again. want to be able to nurse that
68:47 to the point where they can walk do things on their own. which
68:50 about a year and a half or , at which point that's when it's
68:54 a good idea to start getting And so what's interesting is that thes
68:59 and even breastfeeding actually probably serves to generated production. No GN Rh no
69:07 LH, FSH and LH no ovulate cycle. So this is lactation and
69:15 . Um, specifically serve as a birth control to ensure that babies are
69:22 born wide enough apart so that they the highest chance of survival. And
69:28 you've ever gone back and looked at and you start looking at your life
69:32 trees, especially here in the when you start looking in the 18
69:36 and stuff, if you look at birth years for these people in the
69:39 hundreds, where they didn't have any control, most kids and most most
69:44 have kids that are born every two , about two years apart. And
69:49 your family is a large family, does the same thing about about every
69:52 years. Every all the kids are by about two years. That's the
69:57 birth, and so that's what I for you. That is reproduction in
70:01 nutshell. We just kind of sprinted everything. Um, are there any
70:07 about any of the things that we've about? All right. Don't see
70:16 yet. Well, just remember, have a final coming up. I
70:20 try to contact you. It's two right now. I've got saw.
70:25 , I don't know. Since I class, I've received 15 emails from
70:30 freshman about stuff. Um Oh, Lord. There's other stuff I have
70:37 deal with anyway. Eso we We got a final coming up in
70:42 couple of weeks. I'll have that set up for you, remember?
70:46 covers the material since the third So it's really just the fourth
70:51 I'll contact you guys. I'll send an email here a soon as I
70:56 with this other garbage about peer Maybe I'll just do it tomorrow and
71:00 that way. You guys who, who does it will have like the
71:03 to do it. Um, and take it from there. Are there
71:08 questions about the class? Any questions the extra credit? Any questions about
71:13 you guys know about the ex right? Just do your course evaluations
71:18 get up. Get class up to . Heroin gets two points.
71:22 All right. Good. Thank Laura. Well, if there's nothing
71:29 , you know, I hope you the class. I hope you learned
71:32 . Um, You know, I you know the semester. Your finals
71:38 well, and that we come Game busters don't blow anything off.
71:43 the cold weather while we have This is used winter right here.
71:49 I enjoyed teaching. You hope you something. You're welcome. All
71:56 on. Um if you need to in touch me, you could go
71:59 and email me. I'm not gonna any official office hours, but if
72:02 need to weaken, pull you in something like that. So you guys
72:07 a great one. I'm gonna Stop
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