Penis
- Penis
Penis - male copulatory organ.
The penis is built of three columns of erectile tissue :
- the two corpora cavernosa and
- one corpus spongiosum which lies below them
The end of corpus spongiosum is enlarged and cone-shaped and forms so called
glans penis.
Erection is achieved by influx of blood into a labirynth of blood vessels. The
vessels are distended and reflex muscle contraction around veins traps blood in
vessels of erectile tissue.
The urethra that is the last part of urinary tract traverses the corpus
spongiosum and its end lies on the tip of the glans penis. Apart from being
a passage for urine it also is for semen ejaculation.
A loose fold of skin partly covering the glans is called prepuce.
Related subjects : impotence, priapismus, circumcision, [[sexual intercourse]].