 Hey everybody, Dr. O here. We're going to talk about the urethra's in this video, the male and female urethra. You see them both here. Obviously, when you look at them side by side, the key difference is going to be the length. The female urethra's going to be much shorter. The male urethra's going to be a lot longer. As far as histologically, the beginning of the urethra is going to be transitional epithelium. In both males and females, the terminal end will become non-charitonized stratified squamous epithelium, which makes sense. These are generally going to be more protected and stratified squamous epithelium is going to be a lot more protective than transitional epithelium, but just a quick histological review. Before we look at the male and female urethra, I want you to see the beginning of it. At the bottom here, you see the urethra. The urethra is going to be at the base of the bladder, so it's going to be inferior to the bladder. You can see above there, the ureters between the ureters and then the urethra basically form this triangle called the trigone. We'll talk about that when we cover the bladder. I want you to see the muscles involved here. As you transition from the bladder to the urethra, you're going to see an internal urethral sphincter, which is made of smooth muscle, and an external urethral sphincter made of skeletal muscle. These are the two muscles that keep urine out of the urethra, keep them in the bladder. If you want to myctorate or urinate, these muscles have to both relax. We'll cover that more when we talk about the bladder and mycterition, but I just want to make sure that you see that. The proximal urethra is going to be right at the end or right where these muscles are, the smooth muscle of the internal urethral sphincter, skeletal muscle of the external urethral sphincter. Let's go and look at the male first, because the male's got several parts. The male urethra is going to be an average of about eight inches in length. It's going to, so it's got three parts. It's going to pass through the prostate gland, as you can see there. That's going to be the part known as the prostatic urethra. Then we have the membranous urethra is going to be the part that passes through what's called the urogenital diaphragm, so a little tiny piece there. Then the penile or spongy urethra is going to travel the length of the penis, and that's actually going to be, we'll cover penis anatomy later, but that's going to be in what's called the corpus spongiosum. You have the prostatic urethra, it's all one too, but the portion running through the prostate gland is called the prostatic urethra. The membranous urethra is running through that little teeny urogenital diaphragm about a centimeter. Then we have the penile or spongy urethra running through the corpus spongiosum of the penis, so that's the male urethra. Female urethra gets talked about more because of the UTIs, so you see that since the urethra is so short and so close to the body, and you see the urethra there just in the anterior vaginal wall, that it's only about four centimeters long though, so there's a very small barrier between the fecal contents coming out of the anus and contents getting into the urethra, so this is why women are much more likely to get UTIs. Not only that, but it's a shorter, straighter path for organisms to get from the end of the urethra into the body, so the anatomical difference between the male and female urethra is the reason women are so much more likely to get UTIs. Okay, so I think that's all I got to know about the urethra. It's pretty straightforward. We'll talk about it again when we get to the reproductive system in males, but I think that's plenty. Okay, I hope this helps. Have a wonderful day. Be blessed.