Anatomy of the Penis,Male Sexual Anatomy,Anatomy of the Intact Penis,Sexual Anatomy of Men

Facts About Male Sex Organ

Anatomy of the Penis

The Structure of Penis

The outer foreskin layer is a continuation of the skin of the shaft of the penis.

The inner foreskin layer is not just "skin," but mucocutaneous tissue of a unique type found nowhere else on the body.

The ridged band is the interface (join) between the outer and inner foreskin layers. When the penis is not erect, it tightens to narrow the foreskin opening. During erection, the ridged band forms ridges that go all the way around, about halfway down the shaft.

The glans or glans penis (head of the penis) is reddish, smooth, shiny, moist and extremely sensitive.

The frenulum, or frenum, is a connecting membrane on the underside of the penis, similar to that beneath the tongue.

Frontal View of Penis

The penis is made up of three separate cylinders (see the picture below). The two paired cylinders called the corpora cavernosa make up the majority of the bulk and the erectile functioning of the penis. Both these cylinders actually communicate with each other for approximately three-quarters of their length through small holes between the cylinders. (This is why penile injections are applied into only one shaft or cylinder of the penis.) As the penis approaches the body, these two cylinders split and are anchored to the pelvic bone by a tough membrane. Each of these cylinders is encased in a very tough thick sheath called the tunica albuginea. A tough thick membrane surrounds the penis so that when it is filled with blood under pressure it creates a firm structure that allows penetration.

The third cylinder of the penis is called the corpus spongiosum, and it contains the urethra. The tissue around this erectile body is much thinner, and the cylinder actually sits in a groove created by the other two cylinders. As this structure approaches the end of the penis, it becomes swollen and is known as the glans, or the head of the penis. As this layer gets closer to the body, it expands to form the bulb. Covering all three of these cylinders is a thick tough membrane called Buck's fascia. Finally, a final layer covers this area called Colles fascia, or the superficial layer. This is actually continuous with the abdominal wall and makes this whole supporting structure of the penis very tough, allowing it to take quite a bit of force and trauma.