 Hey, everybody, Dr. O. In this video, we're going to talk about all the accessory glands that help produce semen. Remember, semen is only 5% give or take for Mattozoa. The rest of it is going to be produced by these accessory glands. So we're going to look at the seminal vesicles, the prostate gland, and then your bulb urethral glands here. So the primary functions of them as a whole are to activate sperm. So when sperm are first produced, they're very immature, and they have to slowly be activated. The coolest thing to me is sperm are not fully activated until they're inside the female reproductive system. So chemical messengers from the female reproductive tract are what finish off this capacitation or capacitance process where sperm are fully activated. I find that very, very cool. Number two, providing the nutrients, a lot of that's going to come from the seminal vesicles, helping to move and propel the sperm as the ejaculate is very important. And then lastly, buffers to neutralize the potentially acidic environment of the urethra. Because remember, it's shared by the urinary system as well. All right, let's look first at the seminal vesicles. So sperm is traveling through the ductus deference here, and it reaches that ampula of the ductus deference, which then fuses with the ducts from the seminal vesicles to produce the ejaculatory duct. So before it travels through the ejaculatory duct into the prostate gland, it's going to pick up the fluid from the seminal vesicles. About 60% of the volume of semen, the volume of an ejaculate, is going to come from the seminal vesicles. Most important function of the fluid from the seminal vesicles is fructose. It's high in fructose, which is the food the sperm is going to use to, I was going to say flap its wings, to propel itself with the flagella, right? That's number one. There are also chemical messengers in here, prostaglandins though, that are going to increase smooth muscle contraction. Not just smooth muscle contraction in the male reproductive tract, but also smooth muscle contraction in the female reproductive tract to help carry semen and sperm towards the uterine tubes where fertilization would occur. The third thing that comes from the seminal vesicles is fibrinogens. So hopefully you recognize that term. When fibrinogen becomes fibrin, we have clots. So it's going to form a temporary clot or plug that will help hold semen inside the vagina and the female reproductive tract, giving it time to get the sperm to its destination. Another thing about seminal vesicles, like you'll see with the prostate gland, the secretions are slightly alkaline to hopefully neutralize the acidity of the male urethra. Okay. So now we've mixed the 5%, the sperm that's coming from the testicles through the ductus deference here, mixed it with the seminal vesicles. Now we have semen, or it's now called semen, and it's going to travel through this short ejaculatory duct where it's going to penetrate into the prostate gland. This process, moving these fluids into the prostate gland, or this discharge into the ejaculatory duct, is going to be what's called emission. So emission occurs, and ejaculation is separate. So emission is moving these fluids into the ejaculatory duct. Ejaculation would be getting the semen out of the body into the female reproductive tract. All right. So the ejaculatory ducts, they're going to reach, now we're at the prostate gland. So the second major accessory gland structure of the male reproductive tract is the prostate gland. Most of the functions here are unknown. So it's kind of, as you can see, it sits right in front of the rectum, which is why a digital rectal exam can actually feel the prostate gland looking for prostate cancer. What else is important there? As far as the fluids involved, about 20, closer to 30% of semen comes in the prostate gland. It is alkaline for buffering purposes. It's pretty thick. I would say there's an antibiotic here called seminal plasmid, but most of the functions of prostatic fluid are unknown. If there is a big one, though, it does play a role in like the seminal vesicles in thickening semen, and then having it become more thin again, the thickening of semen will hopefully hold it in place so that the spermatizoma can reach its destination. The thinning will then allow, really, the thickening process is what happens when the sperm are eating fructose and getting ready to go to work. It then thins as it shoots forward to try to find an oocyte. So the functions of the prostate gland are mainly unknown. If anything, a lot of it's pad news, right? Because it can lead to prostate cancer. But also, if you look at the urethra traveling through the prostate gland, it's a problem. If the prostate gland swells or gets inflamed, it will pinch the urethra, which is why BPH, benign prostatic hypertrophy, or prostate cancer can lead to problems urinating. If I could design the human, I would move the prostate gland off to the side and have a duct that drains into that, but I don't get to do that. All right, so that's the functions of the prostate gland. Not a lot of known functions there, but clearly significant. The last one, now we have the bulb o urethra glands. They're also known as the cowper's glands. Their job is to produce buffers that neutralize that acidity in the urethra from urine, and then also, so it cleans urine out of the urethra, and also to lubricate the penis, especially the head of the penis. All right, so all of these fluids are now going to dump into the meriduct or tract, and then we're going to have ejaculation. So emission is what got the fluid to that ejaculatory duct. Ejaculation will carry it out through the urethra. So remember the three parts of the urethra, I covered this with the urinary system, but you have the prostatic urethra, the part that runs through the prostate gland, the membranous urethra that runs through the urogenital diaphragm, and then the spongy or penile urethra that runs the length of the penis, and that would be how ejaculation would get the semen out of the body into the female reproductive tract. All right, so those are the three major accessory glands of the male reproductive tract. I hope this helps. Have a wonderful day. Be blessed.