male reproductive system the male reproductive system consists of the following primary anatomical structures the test is the ductus deferens our seminal vesicles the urethra the prostate gland Bubble urethral glands and the penis let's start first by discussing the test is the test this is responsible for sperm development and as a result it is the primary sex organ for males because it's what makes spermatogonia I'm in this mid sagittal section of the male pelvis and perineum the test is's shown in yellow and the yellow we take a little section of that there's a light micrograph if we're to go in hundreds of times a magnification and take a stain we got these structures here tons of them that are called seminiferous tubules and in the seminiferous tubules we see in the periphery these very primitive forming I say primitive because they're early in the development of sperm and as they move towards the central lumen of the seminiferous tubules become mature sperm or spermatogonia we take a little illustration of those spermatogonia there before they go into the lumen of the seminiferous tubules the sperm have the following components a head and that's what's housing the haploid amount of DNA 23 chromosomes and the 23rd chromosome is either X or a y giving rise to either male or female progeny the neck is what houses the high concentration mitochondria that's going to take fructose and turned into ATP for propelling the flagellum or tail that's going to be propelling the sperm during ejaculation the temperature necessary for sperm development is three degrees below body temperature and centigrade so 37 degrees centigrade is body temperature so about 34 degrees centigrade is what's necessary for sperm to be developed this is why the test is in males hang outside the body within the scrotal sack and they're not contained within and why the those muscles like the master ik muscle that surrounds will pull the test as closer to the body or relaxed to go farther away to other increased temperature get away so to make sure to keep temperature lower so the testes have the following vascular supply the gonadal arteries the picture the top shows a picture of the abdominal aorta and the picture of the bottom shows an anterior view of the penis with the penis erect the right gonad Allari courses down in this illustration and as soon as it hits that area again right there it goes to the deep inguinal ring through the in Greenock canal and into the spermatic cord that left going out Allari that's showing a step to section on the other side hits that deep and green ring courses through that in greenland canal and down in the spermatic cord and provides arterial supply to these testes the veins are not bilateral that's why I'm going to do these separate the right go natalie ain it's going to then take blood from that right test is and directly up into the inferior vena cava the there's the IVC the left go Natalie Ain is going to draw a blood away from that left testes up all the way in into the left renal vein which then empties into the inferior vena cava so the right go Natalie Ain and left go Natalie ain both drain their associated gonads right goes up to the IVC the left goes up to the left renal vein and then into the IVC the ductus deferens is next is what used to be called the vas deferens so ductus deferens or vas deferens vaz means vessel and this isn't a vessel early early early anatomist thought it was and that term is stock and hence the name vasectomy to cut the ductus deferens or the vas deferens as a form of birth control the word vas is just not right so ductus deferens is the one that we use though many Doc's will use vas as you go in your career the course of these vas deferens comes from the epididymis which is the structure that houses developing sperm over top of the testes and then it's going to course all the way up the spermatic cord up into the inguinal canal and then all the way to the back of the bladder the function of these Seminole and then into this and then join also with the seminal vesicles so let's deck dis deferens let me just finish with this that course is weak all along its function is to then transport sperm during ejaculation any Jack Y elation I'll talk about the difference between those soon but to basically bring those sperm in getting ready for ejaculation out during intercourse now the function of these seminal vesicles of these paired glands in the back of the bladder is a couple of them that these glands produce like a viscous secretion that contains fructose to give energy to the sperm and prostaglandins frybo nogen and fibrinogen part of me and as well as some other enzymes and proteins and these semen they're going to give contribution to semen the second component and a lot a good majority of them ejeculate comprised is from this seminal vesicle and it's going to give nutrients for the sperm and also helping with decreasing the acidity of the vagina because sperm need a more alkaline environment so seminal vesicles produce an alkaline secretion it also helps so the sperm don't coagulate is a posterior view of the bladder and so there's this ductus deferens coming all the way up and there is the seminal vesicle notice that it's paired on either side and then the seminal vesicle and the ductus deferens are going to come together and form in green they're what's called the ejaculatory duct it's what's taking seminal vesicle secretions and sperm coming in from the ductus deferens and bring them down through this ejaculatory duct paired on either side into the urethra now the urethra has the following functions it's two of them one is to avoid the bladder so there's urine inside the bladder urine comes all the way down and then the urethra takes the urine out the penis and into a toilet or tree or whatever now the second function of the urethra is a pathway for semen so their semen coming down the ejaculatory duct and then the urethra takes it out so there is two so a male reproductive system both urine and semen share the same pathway and this is why at the top or the bottom of the bladder at the top of the prostate gland there's a sphincter that contract so in semen are coming through it ensures that semen is not mixed with urine there are three different regions to the urethra first the spongy part of me prosthetic urethra because that's the part that's surrounded by the prostate gland second is the membranous urethra which is there in the urogenital diaphragm and finally the spongy urethra which is in the spongy erectile tissue of the penis also known as the penile urethra the prostate gland is what surrounds the prosthetic urethra and so it's function it's as dense organ that surrounds the urethra it's right below the bladder it's about is just 2 by 3 by 3 centimeters in size and it's got a bunch of these tubular glands and this dense connective tissue around the outside and these different layers and so what happens is these this prostate gland is going to produce us fluid or prosthetic fluid that has glycoproteins and other enzymes and and in this fluids for the exposure an expulsion and ejaculation to help the given motility to sperm it also there's enzymes if there's a cancerous either benign or malignant cancerous components to prostate they secrete this glands secrete a prostate specific antigen known as PSA into the blood and by measuring these levels of PSA you're able to help give it's used to diagnose and monitor prostate cancer it's also at a very easy way because it's a digital rectal exam you'll notice how close that prostate gland is to the rectum and so by inserting a finger up into the anus and rectum you can touch the back of the bladder the back of the prostate gland if it's really large you'll the physician our PA will be able to feel that prostate gland protruding into the rectum the bubble urethral glands shown there in yellow and it's found in the urogenital diaphragm of the males and it's paired and its function is to is to secrete it's also known as the CalPERS gland this is what an eponym many people use it's in the ug diaphragm and it empties its contents into the penile urethra this is and it happens during an erection so that these glands have it secretes the inside of the lining of the urethra with a lubrication that helps with reducing frictions so during ejaculation think of it kind of like sliding down a slide that's dry now putting water on it and then sliding down you get far more velocity and so it coats the inside lining of the urethra to increase velocity during ejaculation and also helps neutralize the acidity of some droplets of urine that might still be there in this posterior view we see those two paired bulbourethral glands within the ug diaphragm oh there it is and then during ejaculation it coats the inside of the Reetha pardon me there for ejaculation so here we have now the penis the main copulatory organ of the male reproductive system and there's the body or shaft of the penis it's got a legs and body that are found right within the issue Oh pubic ramus of the pelvis and then the main shaft that hangs off the front of the pubic bone the glans penis or the head of the penis is at the very tip it has the highest concentration of sensory organs of sensory neurons which brings the pleasure associated with intercourse the corpora cavernosa perme corpora cavernosa it's paired is erectile tissue found within the shaft and body of the penis this is like a sponge that fills up with blood that enables the penis to become erect for insertion in vagina during intercourse in this coronal section through the penis we see this paired corpora Nosa all the way down and on the one side you can see the central artery that's going to leak blood into this erectile or spongy tissue to help the penis become erect and then we also and then in this other step dissection we see these paired corpora cavernosa that flanked on the dorsal surface of the penis to either side of the urethra the corpus spongiosum is the erectile tissue that surrounds the urethra and is found in the head of the penis and so in this coronal section there we have that corpus spongiosum that is also rectal tissue and expands it helps keep the lumen of the urethra is open and patent as possible and in this step dissection there's the corpus spongiosum in that tube in the middle is the urethra now semen just to overview semen is a collection of all the contribution a semen is the end product of each of these four contributors so for example from the test is that's what gives us the sperm that we find in the semen we have the seminal vesicles that's where we're going to get that the prostaglandins and the fructose and the alkaline secretions to contribute to semen a good measure 60 to 70 percent of the contributions of semen come from this prostate gland has those enzymes and glycoproteins are going to give like 30 percent of the contributions the bubble urethral glands line the inside is a very small percentage only a few percentage of the concentration of the semen comes from the bulbar urethra gland but those are all the structures that contribute to semen which exits the penis during ejaculation