The Penis, Testes and More — Know Your Body


Here at Nopebook HQ we love the D, and by that we mean Vitamin D which helps us absorb calcium for healthy bones. Now that we’ve got that out of the way, it’s time to discuss the reproductive and urinary anatomy of most penis-owners who would typically be assigned male at birth. Here, we’ll be referring to naturally occurring parts of the body – although penises can be constructed during sex realignment surgery as well – we’ll look to cover that separately in the future.

Editors Note: Although this article is for international mens’ day, we recognise at The Nopebook that not all men possess this anatomy and not all people possessing this anatomy are men. This article is merely for your information.

Behold The Mighty Penis

When looking at a penis, you could be forgiven for thinking that it is merely a drainpipe wrapped in sausage meat, however there is a lot more to one-eyed Willy than meets the, well, eye. In fact the cervix-crusader is actually quite complicated.

On the outside, the Penis has some notable features:

  • The urethral meatus
  • The glans, known as the head
  • The corona
  • The frenum or frenulum
  • The shaft
  • The prepuce, more commonly known as foreskin, which you only have if you’re uncircumcised.

The urethral meatus is the opening of the urethra, which can be found at the tip of the penis. This is where the body expels urine, semen and pre-ejaculatory fluid. That’s right, the urethra performs both reproductive and urinary functions. This differs quite a bit from vagina-owners, as the vagina and urethra are separate orifices (but still close enough that UTIs can be a serious problem).

In the centre of the glans/head is where the urethral meatus can be located. You can’t miss the glans, it is the helmet-shape, rotund end of the penis.

The corona is the little ridge that runs all around the bottom of the glans. Just under where the corona makes a V shape, is the frenum.

The shaft is the rest of the penis, if it’s not the head, it’s the shaft. You’ll be able to see veins bulging under the skin on the shaft whenever the penis is erect, that is where the blood is flowing after all, and it is perfectly normal.


If you are not circumcised then you will have a loose tube of skin that grows out from the shaft, just below the head and usually covers the glans like a little sleeping bag, whenever the penis is flaccid. This is the prepuce, which you may recognise as the foreskin.

If you do have foreskin it should be easily pulled back from the head of the penis, if it is difficult, painful or downright impossible, you should get that checked out by a doctor. Being unable to retract the foreskin can make sexual activities, including masturbation, unpleasant and painful. Remember, you need to be able to retract the foreskin in order to put on a condom correctly; safety first people!

Pubic hair is completely natural, so don’t be surprised if there are some growing on the shaft, as well as at the base. Where there’s pubic hair, there’s sweat glands, and where there’s sweat glands, there’s the chance of getting a spot. So don’t be alarmed if you find a blemish on your todger that looks like it could belong on your nose, chances are, it’s just a regular spot. BUT if it looks like a rash, coldsore or wart, go to your local clinic and get checked out.

Life on the Inside

The urethra is the long tube that runs the length of your penis and connects to several organs inside your body.  In fact, thanks to the length means that penis-owners are less susceptible to UTIs than their vulva-owning counterparts.

The urethra is a one-way street, everything that comes out of your penis has to travel through it – urine, pre-ejaculatory fluid (precum), and semen. It’s actually quite sensitive and delicate, and can easily get scarred or infected if you don’t treat it with the care it deserves. Remember, even if you’re curious, DO NOT STICK ANYTHING UP YOUR URETHRA. Just don’t. You could end up horrifically damaged or requiring surgery on your penis.

If your urethra burns or itches, especially when you pee, or you are excreting a yellow or green, foamy or bloody discharge, go to a sexual health clinic or see a doctor immediately.

The penis gets stiff because of blood, but it doesn’t just fill up your artful throbber like a water balloon, oh no. When blood flows into the penis to create an erection, it fills up two spongy bodies of tissue that run the length of the penis. The corpus cavernosum runs along the top of the penis, and the corpus spongiosum, which is parallel to the urethra.

The corpus cavernosum and the corpus spongiosum both continue a little way into the body, which gives the leverage so that they get stiff, when filled with blood, and the penis becomes both hard and erect.

Although erections are often associated with sexual arousal, an erection can happen at any time, in any place, sometimes for no reason at all. They just happen. Additionally, an erection is not a prerequisite for sexual pleasure. There are a ton of sensations that can feel amazing without involving the penis.

Testes, Testes, 1, 2, 3…

The little sack of skin lined with muscle that hangs below your penis is the scrotum. This sack encloses the testes, or testicles. Internally, the scrotum has two separate internal chambers, with a wall of muscle dividing the halves. Externally there is a definite line, called the raphe, that goes down the centre of the sack. The muscles  pull the testes closer to the body to keep them warm, or protect them; when the muscles relax, the testes hang quite a bit lower. The testes are about the size and shape of a large olive, you’ll never look at a martini the same way again. They’re incredibly sensitive to touch and pressure, even a tap can cause extreme pain.


Sperm and the hormone testosterone are both made in the testes. Testosterone is also produced by the adrenal glands, which is actually the source of testosterone for vagina-owners. Sperm is formed in the testes and then moves into the epididymis to mature.

The epididymis consists of a little bundle of squiggly tubes and can be found atop the testicle. During ejaculation sperm travel from the epididymis into the vas deferens. These are the tubes that take sperm up and out so they can be ejaculated as a part of semen. Sperm that don’t get expelled live in the epididymis for around four to six weeks before they eventually die and are reabsorbed into the body. This is why the “blue-balls” is but an urban legend.

Sperm Me Your Excuses

Sperm travels through the vas deferens into the seminal vesicles – here sperm get mixed with some of the other ingredients that make semen. Seminal fluid is made up of 2% semen, 98% other fluids. Those fluids are produced by the prostate, the bulbourethral or Cowper’s glands, and are added at various points along the way before the semen is ejaculated.


Pre-ejaculate is a slippery, sticky mucus from the bulbourethral glands (Cowper’s glands) and helps protect the sperm from acidic environments, ensuring that sperms survives as long as possible. If outside the penis is the outback, precum is Bear Gryllis.

The prostate gland is a chestnut-shaped gland that surrounds a small part of the urethra, below the bladder. It is the point at which fluids from the prostate get mixed into the semen. The prostate is very sensitive to pressure and touch. In fact, a number of people enjoy having their prostates stimulated, which is usually done by inserting a lubricated and glove covered finger or suitable toy into the anus, although testicular or perineum massage can stimulate the prostate indirectly.

Common Disorders Involving Penises, Testes and More

If you’re having problems during sex or when performing any other functions associated with the penis including urination – see your doctor.

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