The
parts of a penis are three: the urethra, through which urine passes,
the shaft and the glans, the sensitive tip of the penis that biologically
corresponds to a woman's clitoris. Separated from the shaft of
the penis by a sensitive ring of tissue known as the corona, the
glans contains a multitude of nerve endings, making it extremely
sensitive to stimulation.
At birth, the glans is covered by the foreskin; however, many
men have their foreskins removed by a surgical procedure known
as circumcision shortly after birth. The area of skin below the
glans, on the exterior side of the penis, is the frenulum, which
many men enjoy having stimulated.
The
urethra, an eight to nine-inch tube that originates within a man's
body and terminates at the head of the penis, carries both sperm
and urine out of a male's body. When the penis is erect, the flow
of urine is blocked from the urethra, allowing only semen to be
ejaculated at orgasm.
The
penis has three cylinders of erectile tissue: the corpus spongiosum,
through which the urethra passes, and the two corpora cavernosa,
where blood becomes trapped during sexual arousal, producing an
erection. The remaining organs in the male reproductive system
are the testicles and scrotum and the prostate.
How
Does it Work? An erection is the result of two areas of your
body collaborating: Impulses from the brain combine with impulses
generated by stimulation of the genitals to cause blood to flow
into the penis. In other words, your brain sends signals to your
penis telling it to become erect. This process, known as psychogenic
erection, is usually the result of intellectual, emotional or
visual stimulation. At the same time, stimulation of your genitals,
known as reflexogenic erection, causes blood to rush to the corpora
cavernosa.
Sexual
Dysfunction. Sexual dysfunction is any condition that affects
the "normal" functioning of a person's sexuality. Note that the
word normal is in quotes! "Normal" is anything you experience
regularly. So if your penis stops doing something it usually does,
you may have a form of dysfunction. Types of sexual dysfunction
affecting the penis include the following: