we are live again okay so we just finished our first part of the chapter on reproduction once again guys I'm going to give you the whole Spiel because this is a new YouTube video check the links in the description for uh the sign up link for the email list to join the WhatsApp group for updates to donate to this channel if you feel like it you don't have to but it's definitely appreciated the buy me a coffee and my venmo are always down there and 50% of proceeds always go to charity um you can also find the Drive Link which will tell you everything about this program it has all of my study guide stuff it has um obviously the lecture email list all the things that I think are important for studying for the MCAT I'm going to start adding Anki stuff in there as well and I have a whole video about how to use Anki properly so you guys can find that um as well on my channel am I missing anything uh lectures subscribe like you know pop some confetti have a Jolly Rancher right um hit the Bell not right hit the Bell button even though like I don't know why you would want notifications about the MCAT on your phone all the time uh and lecture until further notice and the reason I say until further notice is because my schedule shifts like every six weeks because of rotations lecture until further notice is on Tuesdays and Wednesdays from 6:30 to 9:30 p.m. EST that's what I was missing there is a link in the description to join the lecture live on Zoom every week thank you guys so much for your participation let's get back into the lecture so this was the conclusion of our discussion of cellular reproduction and now we're going to talk about human reproduction right so we have to begin with the reproductive system the reproductive system it's about to get real Diddy in here can't believe he got arrested that's so funny to me like he got arrested and they found a you guys know who I'm talking about right P Diddy he he got arrested and they found 1,000 bottles of lubricant in his house so it's about to get real Diddy in here know huh that's really weird he's he's a strange individual he's a really strange individual I hope I hope to God I ever meet someone like P Diddy or maybe I already have and I don't know they could even be in this room okay so physical sex is determined by the 23rd pair of chromosomes if if you inherit two X chromosomes you are genetically and phenotypically female and you have the female body habitus and you will develop a female reproductive system granted nothing goes wrong and if you inherit an X chromosome and a y chromosome you are going to be phenotypically and genetically male and you will develop the male body habitus and have a male reproductive system granted nothing goes wrong because a lot of things can go wrong X chromosome mutations can cause XL disorders I know no one's going to get this question right what is the xlink dominant disorder that I discussed with you guys last year huh no that's exing for cess actually let me let me fact check myself on this before I ask the question it's not color blindness let me make sure of this okay yeah if if this disease is inherited it is inherited an XL dominant pattern which is why it only happens really in women CU when it happens in men they just die in utero did anyone in chat answer properly it is R syndrome holy yeah it's a r syndrome who said that who said that wow absolutely incredible no not Tourette Syndrome it's a r syndrome yeah yeah R syndrome absolutely incredible that is that is so low yield catch you a virtual Jolly yeah virtual Jolly raner it is called RH syndrome and Rh syndrome is a really that is so incredible that someone knew that huh excelling dominant yeah it's inherited in an xlink dominant pattern wow masal man that is that is incredible that's really good uh R syndrome is actually a disease that only affects females when you see it in in the wild right and uh basically these girls they develop properly and then all of a sudden when they're like usually two 2 and 1 half years old they just start to Decay they lose their ability to talk they can't walk properly they have learning disabilities and characteristically they have like this hand ringing movement that they do they ring out their hands and they touch their lips with their hands a lot for whatever reason and uh I think it's fatal I'm pretty sure huh basically yeah like like that's kind of what happens um but yeah it's uh it's pretty bad not good definitely not good color blindness is excellent processive we'll talk about that when we talk about genetics and when we talk about me which we always do okay so XL uh disorders carried on the X chromosome which means who's more more likely to have an x-link disorder a male or a female a male why a male they only have one so they only have one chance and then if that's up you're up the women they have two chances right so if one of them's messed up if it's re recessive if it's recessive and one of them is messed up you might still be okay but if both of them are messed up then you have it and that's how color blindness works so I guess we can talk about it now so color blindness by the way am I recording over here yeah okay good so color blindness is an excelling processive disorder meaning that when the X chromosome is affected if you still have another good X chromosome you don't show the disease but what happens you're labeled as a carrier right so that was my mom my mom got the X chromosome from her dad of course she did because she clearly didn't get the Y chromosome from her dad and then got a good X chromosome or a non you know unaffected X chromosome from her mom right then when my mom had kids with my dad So within having boys if this is how the question usually gets phrased on the MCAT if assuming the child is a boy what's the likelyhood of having blah blah blah disease right so assuming the child's a boy what's the likelihood of having color blindness 50% so basically I got color blindness off a coin flip right because I had to get an ex chromosome from my mom because I need an X chromosome everyone needs an X chromosome you don't have an X chromosome you die right and then I only could have gotten the Y from my dad so since my mom had one good one one bad one it was just a coin flare right what are the chances that given that the child is female that they have color blindness zero because that is not exhibiting the trait but it's possible that one of my two sisters looks like this and they'll have a son that's color blind right so what does my family tree kind of look like my mom who's a carrier my dad who's not affected right and let's do her mom and her dad right and then my dad's dad and my dad's mom right so my mom who's not affected and my dad had three kids my oldest sister my middle sister and me who's affected right let's say my oldest sister actually has the trait if my oldest sister has kids what's the chance that this kid has color blindness zero what's the chance that this kid has color blindness 50 could be either or right what about if I have kids what's the chance that this kid has C blindness zero she can be a carrier so like a quarter right but not even like expressing so she could be a questionable carrier what about this kid impossible why because you don't know the status of the mom and what's he getting from me the Y chromosome he's not getting the X chromosome from me if he was he'd be and if he was he wouldn't be a he either but I'm not going to get into that discussion okay did a SE section today in the morning and like when you do a c like I never realized until I did OBG how violent C-sections are so they'll give you like the the anesthesia blah blah blah whatever and they have to get to the uterus right so basically you got like the skin the belly button and they cut through that and then well they don't cut through like this they do the fan and steel incision which looks like like that and they cut through that and when they open it up so here's the skin and it's opened up like this and then underneath that have the fat they cut through the fat they get to the muscles the abdominal muscles the rectus muscles they basically just slide their finger in between the rectus muscles remove them from one another cuz pregnancy makes them separate anyways and you get two people and one person takes one side of the rectus muscles and the other person takes the other and they just pull they just pull the muscles apart like they literally the woman's on the table she can't feel the pain but she can feel the pressure so they just pull the whole freaking incision AP like violently because these muscles are really strong and you got to open up space for the uterus to like move out so the baby can pop out of the literal stomach so they grab it and they pull it apart like that and now the thing is you have some attendings who are like younger and have not been in practice for that long not many at Kings County but like you'll see videos of it and um that's where I'm doing my rotation so you'll see videos of it where like they'll go like this and then they'll pull like gently and they'll go slowly there's some attend just go there's like tear up because it doesn't make a difference like there's already gonna be trauma there right so it's it's crazy crazy crazy crazy uh I mean like as a medical student like you're there you're suctioning obviously retracting blah blah blah you're helping with like surgical instruments and at the end when the attendant kind of disappears to go write the note or like see the patient's family or everything they they'll let you suure like they'll let you throw a stitch um things like that so i' I've like helped stitch up a f still before it's fun uh not that you're like on top of the world doing everything but some attendings are a lot nicer than others some attendings are just like just stand there and do nothing it really depends on who you're working with um but yeah so that's fun um very scary to see but you know okay back to this so we talked a little bit about the X and Y chromosomes oops okay so the Y chromosome uh carries very little genetic info and like I said in the last lecture the Y chromosome carries the SR y Gene and when this Gene activate it codes for the production of male parts and a male body habitus and a male human being right um when does it activates like the sixth or seventh week of gestation I believe um and then what happens after it activates if the sry gene fails to activate which can happen right so like you can have a y chromosome that has a deletion of the sry Y Gene the fetus will actually develop as a phenotypic female so in the absence of the Y chromosome or in the absence of the sry gene all of us would have developed female right and there are some diseases where everything's male except for the genitalia right it's very interesting I feel so weird to touch my laptop with a chalk on my hands okay let's talk about male reproductive Anatomy because in biology men are a lot simpler right and of course sometimes that's a good thing and sometimes it's a bad thing in biology it's a great thing that it's a lot easier to learn about men than it is to learn about female reproductive Anatomy female reproductive Anatomy is some of the most difficult I've ever encountered my entire life it's very hard to learn it's why we have a whole branch of medicine dedicated to women it's called OBGYN you don't have that for men you have Urology but it's not really like OBGYN like obgy is just Fe like women's medicine Urology is like what's wrong with your dick ah but there's an argument to be made about the fact that like all of medicine was for men at some point and we'll talk about the social ramifications of you know OBGYN another day male reproductive anatom the primitive gonads develop into the testes which are kind of like the HQ of all of male reproductive Anatomy correct where do the testes sit in the body they sit yeah outside the body they're not inside the body like the ovaries they sit outside the actual body cavity right they sit inside the scoto and they hang below the body anterior to the perineum what is the perineum it's the space between uh the anterior of your crotch and your rectum that's the perineum right and for women it's the space between the bottom of the vagina and the rectum right why do they sit in like this little sack called the scrotum anyone know why they exist like outside the body heat yeah so when sperm are being produced they can actually only be produced at a very specific temperature and it's not body temperature which is weird very weird design right so the testes actually don't live well inside the body like the ovaries do so the scrotum can actually drop down and rise up towards the body and use the body heat to regulate its temperature depending on how low or how high it hangs and that is not something men can control that is purely autonomic nervous system happens by itself right so for the men if you're ever in a very very hot like desert day or you're in the freezing cold there is a difference in how your scrotum hangs from your body right that's controlled by things that we are in no control of okay the testes have these things called seminiferous tubules and these are the functional unit that's my little thing for functional of the testes and what do they make sperm and they are nourished by ctoi cells a specific type of cell inside of the male genital tract just looking at something up real quick all right so CI cells help to produce sperm they help the seules to produce sperm right then we have another type of cell in the testy or the testice right called the interstitial cell of leig the interstitial cell of leig and this is another functional unit of the uh the testicle that makes what androgens like testosterone what are androgens they're sex hormones but specifically sex hormones that are in estrogens so let's start a little diagram here's a testicle right here and that testicle has something on top of it that we're going to talk about in a minute and then that top thing actually connects up into this other thing that we're going to talk about in a minute right so sperm are actually passed from the SE seminiferous tubules over into another place so I'm going to erase this so let's track the sperm as they move along the reproductive tract so sperm in inside of the seminiferous tubules move into the this is called the epidemis told you it was about to get Diddy in here the epid didus shaking your head is the proper response to that the epidemis right and the epidemis is where the fella gain their motility that's a high yield fact as well maybe not for the mcap but for medical school for sure right so if you were to take sperm from the testicle itself you actually wouldn't see them move because they haven't gained their motility yet the fella gain motility in the epidemis and the epidemis is important because this is where sperm are stored until they're needed and when are they needed ejaculation real gooner going on over here this tube is called the vast Defence and sperm are going to travel up through the vast Defence up to what into the ejaculatory duck right so they're going to come into this duct and it's going to pass through this gland behind this gland it's going to come into this place called the ejaculatory duct what is that gland that's passing behind the prostate gland the prostate GL is that big little ball that it's passing by hopefully it's not too big I have prostate cancer which is not good definitely not good I don't think any cancer is good yeah I think so Chadwick Boseman he had some form of cancer I don't know if it was prostate cancer but um cancer is normally a cancer of like older men I didn't know how old he was but yeah I do know he died of cancer very unfortunate the two ejaculatory duct this one on this side there one on the other side they meet in the urethra right and that exits out through the penis of course so the urethra runs through the penis and then gets ejaculated out along the path here you also have things known as seminal vesicles and the bulbo urethal gland also known as the cpers gland seminol vesicles make seminal fluid which the sperm mixes with in order to help it move correct the seminal V vesicles also give it the fructose that it's going to use to power itself for the rest of the journey that it's going on right and the cpers gland actually makes a clear viscous fluid that cleans the urethra before ejaculation I don't know what we collo call this fluid it's called precom yeah so this fluid is precom colloquially I tried to find a nicer way to say that but there's no really like generic way to say that without making a reference to vulgarity but yes that fluid is precom and why do we need to expel that well it's because urine that also passes through the urethra is toxic to sperm right urine is toxic to sperm so this is going to go ahead and clear out any remnants of that urine or anything that was inside of it before the sperm come and go on their merry way one more thing the prostate gland actually has a purpose this big gland right here this prostate gland helps to make the semen which is just the sperm plus the seminol fluid helps to make the seen alkaline why because what's acidic the vagina the vagina is acidic the vagina has a pH around 4.5 four to 4.5 let me double check that 3.8 to 4.2 so that alkalinity helps it to survive inside of the vagina right cool there is a pneumonic to remember all of this what's the pneumonic seven up very good so let's talk about the path of the sperm through the male reproductive tract okay so s where do they begin the seminiferous tubules they get passed off to the epidemis then to the vast Defence also what is the surgery where you clip the vast difference a vasectomy and that is male sterilization do you see how it works now sperm can't get up from the epidemis to the vast Defence so they never get out of the body however theames do fail vast difference then to the ejaculatory duct n stands for nothing because they just didn't want to make it SE up they needed something then to the urethra and then to the penis everything here is bilateral after that it's one thing how many sperm are there in one ejaculation too many I actually forget the specific number you said 20,000 so I think there's like 5 million in 1 millit so it's between 80 and 300 million yeah and only one gets to do the job hey it's about to get Diddy in here that's disgusting I hate myself let's talk about women what time is it huh 8:43 not bad any questions from Zoom chat just yapping yeah so what are the main gonads in females the ovaries right they consist of thousands of follicles and in each of these follicles there is an ovam which is an egg and every month one egg per month is released into what it's released into the abdominal cavity is released into the peronal cavity right because you know the abdomen is lined by peritoneum right so it's releasing the parital cavity and it's actually picked up by the fallopian tube the ovam isn't actually releasing the fallopian tube like I once thought it was it is released into the paral cavity and then fima pick it up but if the fmria don't pick it up it might end up somewhere else and that's one of the thoughts about how an ectopic pregnancy happens outside the fallopian tube most ectopic pregnancies are inside the fallopian tube or in the wrong part of the uterus got to see an ectopic pregnancy actually it was very interesting so like I said before the anatomy diagram ovary fimbria fallopian tube uterus cervix vagina fallopian tube fimbria ovary ovary releases the egg egg goes into the fallopian tube follows down here possibly gets fertiliz follows down and comes into the uterus does that make sense vagina cervix uterus fallopian tube ovary you might realize if you're following along with the book I skipped over something I skipped over spermatogenesis and now I'm also going to skip over oh Genesis production of sperm and production of eggs you know why I really don't care for them personally I'm not saying you shouldn't care for them you should I just hate them I never learn them properly I don't want to learn them properly I don't care enough about them and I made it this far without it so I'm not teaching it but if you want to figure it out figure it out and be my guest and maybe you can make a video about it and teach all of us I'm being serious because I have never learned this stuff okay it's time to do puberty and the menstrual cycle I need to give you background about hormones hormones are basically just signaling molecules throughout the body right they make things happen by attaching to receptors and then things happen because of it right hormones can be one of two things they can be direct or they can be Tropic right an example of a direct hormone is something like growth hormone growth hormone directly goes and it impacts the cells that it's looking for it goes into the cells it changes the way the cell works and it gives you a response that's a direct hormone a Tropic hormone is something like FSH FSH goes to the ovary and causes the cells of the follicle to produce estrogen and then estrogen goes and has effects it got something to release something that had an effect so it caused the release of a thing that has an effect that's called a Tropic hormone Okay the reason for this is because when you switch over into puberty your B your brain your Bane your brain begins releasing this hormone called gonadotropin releasing hormone so clearly it's a hormone that releases the gonat tropins and the gonadotropins are hormones that are Tropic to the gonads what are the gonads testicles and ovaries right so when you hit puberty this GnRH right which is the abbreviation this GnRH begins to get expressed from your brain what part of the brain the hypothalamus and we'll talk way more in depth about this when we do Endocrinology which is another very difficult chapter but G&R from the hypothalamus signals for the release of the ganat tropins what are the two granat tropins that you need to know you guys know I told you one of them what does FSH stand for follicle stimulating hormone and lutenizing hormones if any person in chat specifically the women has ever been to a fertility clinic not for fertility reasons but maybe because of heavy periods PCOS uh no periods late periods you may have gotten tested for your levels of GNR FSH and LH right so what do these things do so first of all we have to understand where they come from these both come from a part of the brain called the anterior pituitary gland so the hypothalamus signals the anterior pituitary to release these two hormones known as follicle stimulating hormone and lutenizing hormone all right first we're going to talk about what they do in men okay do men have follicles no they don't these two were discovered inside of women clearly right and then we just found out that's the same thing that does stuff inside of men for men follicle stimulating hormone actually stimulates spermatogenesis so for men the s in FSH means sperm and that means lutenizing hormone is responsible for the uh stimulation of testosterone production so FSH stimulates for spermatogenesis and LH stimulates testosterone production and once you make testosterone it feeds back on the hypothalamus and turns off that pathway once's it's high enough negative feedback are you guys ready positive feedback we'll talk about when we do Endocrinology there is one case of positive feedback you need to know which is giving birth oxytocin yeah very good now let's talk about women this whole system of FSH LH GnRH all of it has to do with one thing and one thing only the menstrual cycle the cycle starts at the beginning of Menses which is the shedding of blood what do what are you shedding you're shedding the lining of the endometrium what's the endometrium the uterus has three layers the endometrium the myometrium and I forgot what the outside layer is called I'm drawing a blank I think it's called the har metrium something let me check I should know this I'm literally on OBGYN it is the parametrium cooked okay so the endometrium is on the inside the myometrium is the muscle layer and the perimetrium is the outside layer that connects it all together right so at the beginning of Menses right the shedding of the blood or the shedding of the thickened endometrium you get a big release of what the whole endometrium right and the reason that happens is because I'll tell you two things and it's all going to make the thing is we have to start from here but it's all going to make sense in the end this happened because of a drop off of progesterone right which we haven't even talked about yet right but starting here what happens from the drop off of progesterone is that this shedding actually leads to an increase in [Music] GNR that GNR leads to an increase in FSH and LH and that leads to the production of estrogen by the follicle what's responsible for the estrogen production FSH or LH it's sh cuz the follicle stimulating hormone is going to stimulate the follicle to produce estrogen so the estrogen levels begin to climb right and if you want this is a really good diagram you can find like uh you can look up like Kaplan menstral cycle diagram this is the diagram that I'm basing this off of right if you guys can see it there you can find it online it's a very good diagram right that s estrogen stimulates proliferation of the endometrium and glandular the formation of glands of the deua what's the decidua the decidua is a thick layer of mucus that lines the uterus during pregnancy so basically this genderization makes for a more comfortable environment for implantation of a fertilized egg and what happens in the beginning is that you have this estrogen that comes to a specific level and then the GNR drops back off and the FSH goes back down and it comes to a spec specific level and it comes back down but every time G&R is released because one thing I didn't tell say is that it's released in a pulsatile fashion your estrogen level becomes like a little more than before and a little more than before and a little more than before right and eventually what happens is that late in this phase which is called the follicular phase right if everyone has like a period app now right so when women carry like track their what's up glandular isation like to to make glands out of something yeah proliferation basically same thing so this is called the follicular phase so for any women who track their period on an app it probably tells you like oh follicular phase ludal phase and all that right so this is the follicular phase late in the follicular phase so I told you that estrogen eventually goes back and turns off the pathway right somehow and I still haven't gotten an answer for this despite asking some actual endocrinologists right estrogen when hitting a high point activates GnRH release it does this once and never again once in a month and then it doesn't do it anymore right it activates G&R release and that leads to a massive Spike of FSH and LH so we know what FSH does is going to cause the ovary to make estrogen or sorry the the follicle to produce estrogen right what does LH do well this l H spike is actually what causes ovulation and this is why it's four women in the room right now correct me if I'm wrong about 12 13 days after you get your period you might feel this random very abrupt sharp pain in one side of your body like just right there just like a poke and it stays around for like a day or two that is the rupture of the folicle that is a follicle in the ovary breaking and releasing an ovam because for ovulation to happen basically you have this little follicle that's surrounded by these things called granulosa and Thea cells which are feeding right which are feeding this one little cell in here right and when the Spike happens it slices through this and it escapes yeah so there's no blood in the first place when you have a when you have a hormone IUD not a copper IUD when you have a hormone IUD you don't get your period it doesn't happen because the progesterone in we're going to talk about that in a second but the progesterone inside the IUD shuts down the ovulation that's why you don't get pregnant there's no ovam to I could get into a whole hours long discussion about the implications of hormone iuds and like yeah does it affect your health in many ways because you're messing with your hormones you know in the same sense that if a man goes out there and shoots up testosterone it's going to affect his health it's just less detrimental to women than it is to men to take excess of these hormones because you're just manipulating this system but there are cardiovascular and Bone effects and blah blah blah and like I'm sure you've seen if anyone's on birth control in the room you see the huge research paper that comes attached with birth control and that's all the research studies that have been done that exhibit the different changes that may happen to your body because of the use of birth control right but ovulation so LH Spike cuts through this and then biscuits sent out I have a correction to make Bas from my lecture last year so this is why this year's lecture is better that happens inside the ovary right so the ovam gets sent out what happens to the follicle it stays it stays inside the ovary I always thought that the ruptured follicle would move out with the ovam it stays in the ovary and the reason that it stays in the OV is because the ruptured follicle turns into something known as the Corpus ludum and ludum sounds like luteinizing and that's why LH is actually going to act on the Corpus ludum and the Corpus ludum produces progesterone okay so if it is estrogen's job to to build the uterine lining and glandular and make it thicker and make it bloody and make it thick right what is progesterone's job I want you to remember one word one word only progesterone maintains the uterine lining so as long as you get continuous LH on the Corpus ludum you'll produce progesterone and it maintains the lining and the reason we're maintaining the lining is because we're waiting for that what what's it called we're waiting for that fertilized egg to implant inside of the lining and find itself a cozy little home in there understood are you guys following any questions from Zoom you guys anything take a second we have for this do we have a demonic for this no we do not have a neonic for this if you guys want to make one that'd be great oh oh my God I just I shouldn't have sat down oh God any questions so far well that means I'm doing good sorry the Corpus colossum is the um the neuronal pathway that connects the two halves of the brain yeah exactly right so the Corpus ludum so so let's go over what we learned so far I think I think that's a good place to to be if we're not if we don't have questions so a woman starts bleeding that's the start of her Menses and that means that the progesterone has gone away and I told you that the progesterone is what's deactivating the gonr so the progesterone goes down the gonr turns back on G&R leads to the release of FSH and LH the F the FSH is the one that's responsible for all the activity in the first part of the menstrual cycle FSH travels to the ovaries acts on the follicle leads to the release of estrogen that estrogen builds the endometrial lining and makes a comfy cushy home for the egg the estrogen Rises and Rises and Rises as it rises it turns off the G&R and then it turns back on and it turns off and it turns back on until eventually it hits a point where it turns on the G&R a lot right and you get this G&R storm and you get the LH Spike and the FSH Spike but the LH spike is what causes that engorged follicle to rupture and that follicle releases its ovam when the when the engorged follicle ruptures it turns into the Corpus ludum so the ovom is now traveling into the fallopian tube at the same time that the follicle ruptures and turns into the Corpus ludum which is being acted upon by the massive amount of LH that was just released which is going to release a massive amount of progesterone so that's going to turn off the G&R temporarily but it's also going to go and maintain the uterine lining does that make sense so far if anyone has any questions say it now because when we move on it gets more complicated Zoom chat let's keep it pushing it's funny because I'll like go to my mom and I'm like I know more about you than you do because my mom did not go to medical school but she is much smarter of a person than I am just because she's a mom and there's a certain skill set that comes with being a mom that I will never have okay so we were talking about the corps ludum the prot progesterone Pro okay so let's rewrite number five because it's so important progesterone maintains the uterine lining also known as the endometrium you guys know the disease known as endometriosis endometriosis is a deposit of endometrial tissue where there's not supposed to be endometrial tissue so when you have the release of estrogen you get that crampy pain in various different parts of the body because that's endometrial tissue responding to the estrogen where it's not supposed to be there's case studies of endometrial tissue in the lungs in the central nervous system inside of the momentum and it's crazy endom endometriosis is a big cause of infertility okay now one of two things is going to happen 6A and this is different than last year too I didn't explain both the sides of this 6A is the egg gets fertilized and then that fertilized egg implants and then that implantation leads to the growth of a placenta and those placental tissues create this thing called beta HCG which we'll come back to egg fertilization implantation makes the placenta beta HG which is a gross oversimplification of what happens that is a disgusting oversimplification of what actually happens but it works 6B egg lonely sad egg lonely sad right and then Corpus ludum becomes unresponsive to what what was it responding to before no it was producing progesterone it becomes unresponsive to LH which leads to a drop in the progesterone and what was progesterone doing what is the job of progesterone everyone it maintains the uterin lining so if you drop the progesterone what happens to the uterine lining it sheds so you have a tight window a tight like 10day 10 time period where the progesterone is there the LH is acting on the corpus ludum the brone is there the egg can get fertilized it hasn't implanted yet and you're not bleeding it's a very tight window right so that's what normally happens so once again all the way from the top right just so that people can listen to this and listen to it and listen to it and listen to it you get a shedding of the lining because of a drop in the progesterone so the progesterone is no longer negatively impacting the G&R GNR goes up causes FSH and LH to go up FSH triggers the follicle to produce estrogen estrogen grows the endometrium right and also nurtures the ovom the egg cell that's going to be produced and let out that estrogen reaches a certain Peak after a while and that Peak activates a huge storm of G&R the G&R releases a ton of FSH and LH the FSH spike is what causes ovulation the follicle ruptures turns into the Corpus ludum and releases the ovam into the fallopian tube hopefully that Corpus ludum as acted upon by LH is going to produce progesterone that progesterone maintains the uterine lining and also shuts down the G&R through negative feedback right cyclically it doesn't just do it and then drop off it does it again and again and again and again eventually the LH will be unable to stimulate the Corpus ludum and if that happens the progesterone stops being produced and the endometrial lining is shed do you see why this is such a confusing topic yeah I mean I I was definitely frustrated I don't know if I cried I might have but I was definitely frustrated for a while but then I was able to teach it so I'm not as frustrated anymore wow the handwriting is just falling off the board okay what is this beta HCG thing so if the egg gets fertiliz in in plants and then you get growth of placental tissue this beta HCG It's actually an analog of LH the beta HG is an analog of LH and if it's an analog of LH what do you think it's stimulating the Corpus ludum right so the analog of LH stimulates the Corpus ludum and the Corpus ludum produces progesterone but you know how the Corpus ludum got sick of LH got sick of it doing its job the Corpus ludum never gets sick of beta HCG so the beta h CG stimulates the Corpus ludum and it's permanent it never gets sick of beta HCG and the Corpus ludum will continue to produce progesterone until and new fun fact for this year eventually the placenta takes over in the production of progesterone and that's what maintains the endometrial lining for the whole pregnancy and then when's the next time the lining shed when you have the baby all comes out right all right Zoom chat how we doing okay I swear he said he cried I probably cried not really MCAT relevant but for ectopic pregnancies how does the sperm reach the abdominal cavity since the egg doesn't get picked up by the fallopian tube uh yeah that's a really really really create question uterus cervix uh sorry vagina cervix uterus fallopian tube do people only have sex when they're ovulating no people have sex all the time so it's possible it's possible that a sperm gets in swims all the way over here swims out the fallopian tube right just so happens to to be in the proper position to meet an egg when it's in the abdominal cavity and that egg was not headed towards the fallopian tube it moves out of the abdominal cavity when it gets fertilize and boom you've got a pregnancy in your ass I'm serious here's the vagina sorry here's the uterus and it's anted so this is the uterine cavity flexing over the bladder and then this is the rectum right here which connects up to the sigmoid colon right this space between the uterus and the rectum is called the pouch of Douglas this space between the bladder and the uterus is called the vesico uterine pouch I read a case report and I personally know someone who had an ectopic pregnancy which landed in the pouch of Douglas they had a pregnancy growing between their uterus and their rectum inside their body huh no I mean it literally just causes Mass bleeding and like dysfunction inside of this person's body like first of all it needs to create an environment around itself to try to survive and also it's hormone reactive so it's causing like all these problems so the most common place for an ectopic pregnancy is in the fallopian tube itself so what happens is that you have a normal ovom that comes out like this and gets fertilized in here but for some reason just doesn't move and it just implants right there and it just aggressively messes with the fallopian tube and then what happens is the fallopian tube gets engorged and engorged and engorged until it can't take it anymore and it ruptures that is what we call a ruptured ectopic and that is a surgical emergency because when you have a ruptured ectopic you'll cause abdominal pain and bleeding and the bleeding you might not even see it might be like a little bit of vaginal bleeding because some of that blood comes in the uterus and gets out the vagina but when a woman has abdominal pain and bleeding she's like oh I just got my period early no you're diet you are bleeding out into your abdomen slowly and eventually you're going to bleed out your entire like uh volume of blood and you're going to die of hypovolemia but the thing is the pain of an ectopic pregnancy is far more acute and far sharper and far worse than cramps cramps are a global pain it's like all over from what I understand a ruptur topic is right there because that's where your fallopian tube ripped open what is the treatment for a ruptured ectopic it is called a salpingectomy they have to take out your fallopian tube there's no way around it they go in they cut out your fallopian tube and they get out is the pain constant it might be like acute and then it might just like Wayne off the woman that I saw who had a ruptur deck topic she was having a full conversation with me mildly tacki cardic felt a little nauseous and was just like I felt like this sharp pain yesterday and it hasn't really gone away since it's like dull weird now and we gave her Tylenol she's like yeah I feel much better on the Tylenol we gave her an ultrasound like 100 m collection of blood in her abdomen she's a very rare case she's a super rare case ectopic precies aren't common they're not like common things right okay any questions from Zoom chat anyone I saw someone was talking about lasagna oh man lasagna soup is almost lasagna soup is almost okay um yes me is making super does she even pay attention here like like why is she here like what what is the point of her being here she's not she's just distracting everyone is the lecture finished fomo goes crazy okay wait no that's that's so true I I do this all the time I'm also in auditory learner um do you guys want leure to be done or do you want to hear a story story lecture done or story all right story time so I'll do story time while I clean up so what's a what's a story that's worth telling oh one time on my Cardiology rotation I had a patient who had a um who had a heart attack go figure right this is like a 79y old lady she had a heart attack and basically what happens is that the vessels in the heart the coronary arteries they Supply a big section of the heart muscle right the coronary arteries so in the heart you have two sides you have an Atrium and a ventricle on both sides and then you have this thing called the septum which splits the two sides down the middle it's called the interventricular septum and the interatrial septum right but it's just called the septum she had an infar in the artery that goes over the septum so she lost blood flow to the septum for a bit right until we got the stent inside of her but she lost blood flow for long enough that the septum like died right so the thing is when the heart muscle is alive it's contractile it can handle the pressures right because there's a lot of pressure in the heart now that her septum is dead it can't really handle pressure anymore so when the left ventricle squeezes it cut cuts into the septum a little bit and then it squeezes again and it cuts into the septum a little more and it squeezes again it cuts into the septum a little more until eventually she blew a hole in her septum she tore straight through her septum that's called a septal rupture right so now since there's high pressure in the left side and everyone's saying dude this is right no it's patient left since there's high pressure in the right side and in the left side and there's low pressure in the right side blood is going to flow from left to right and if blood flows from left to right blood's not getting out into the body so she has an interventricular septal rupture and now blood's not getting out into her body but the thing is the thing is normally when people have these sorts of ruptures they die in hours they're gone they're they're goners right this woman was on so many drugs so many like not not like street drugs like actual drugs called pressers to keep her blood pressure up and like help her with her circulation she was on so many of these meds that she had a hole in her heart and she was having a full normal conversation with us she was completely fine and we had to explain to her hey ma'am the moment we pull these drugs it's lights out for you it's over the moment we pull these drugs it's over and everyone's just like why do you have to pull the drugs why doesn't she just live on them for the rest of her life not so fast these drugs are ridiculously toxic to the body if this isn't going to kill her the drugs will and she'll die a much more painful death on these drugs than she will with the hole in her heart at least with the hole in her heart we could take the drugs and taper them down and she would just fall as sleep and never wake up over the next 3 days or so she just said goodbye to her family and she died yeah I mean it it's it's not fun man like it's like I have a lot of I have a lot of fun stories in medicine but like the the ones that stand out are these ones like these are the experiences that you really want to talk about cuz everyone's going to have a good time in medicine everyone has a good time in things they're passionate about but you learn A Life Lesson or two like this one yeah what's up oh she would have died on the spot she would have died in like 30 minutes if she didn't come in um one fun story all right here's a fun story there's another lady who's like 50 something years old and she has a him she has is atrial fibrillation and atrial fibrillation is a problem because you it increases your risk of making clots which can give you a stroke or like any other clot in the body things like that so we have to shock her back into heart rhythm right so we get out a cardioverter while we're doing like a you know trans esophageal echocardiography so we put her under with anesthesia we look inside the the throat to look at the back side of her heart to look at the left atrial appendage and see some Imaging back there and then anesthesia is like well we got to wake her up and we're like wait we have a better way of waking her up so we can kill two birds with one stone we can wake her up with the shock that'll put her back in a normal heart rhythm and anesia is like well there's no contraindication so we'll do it right so the lady's in active apib she has like a heart rate of like 167 Baseline her heart's going crazy because the Atria are just firing whenever they want and then Dr Dr B who I'm not going to name because you don't even know what institution I'm at when I'm doing this comes over there's a little device that shows her crazy Rhythm and he just comes over and he waits for the time and he presses and holds this button and this lady dead asleep on the on the on the bed leaps out of literally jumps out of the bed and slams back down into it wakes up gasps for air and starts crying and I'm just like but then you look at the machine and she is a completely normal Rhythm 67 beats per minute completely reset her heart which was Subhan Allah it was ridiculous it was the most insane thing I've ever seen that humans are capable of doing that right so like like completely normal heart rhythm 67 beats per minute she's alive she's breathing right she's fine she's not going to have a stroke anymore but she's wailing in this bed so I asked as the fellow I was just like what the hell just happened why did she start crying like I assume it's painful but why is she like wailing like she literally just you know had the worst time of her life he's like everyone who has gotten a um cardio version done says it's like waking up from the worst dream you've ever had so you're basically like inducing a panic attack in this person but you save her heart so that's the story of some of the two of the coolest things I saw on my Cardiology rotation thank you guys so much for listening I hope you enjoyed the lecture I hope you learned something and I will see you next Tuesday see you later Zoom chat uh you guys don't have to leave yet but