How Does Erection Normally Happen?
An erection requires an interaction between the brain, nerves,
hormones, and blood vessels of the body. an erection does not
necessarily require or lead to ejaculation or orgasm. An erection
of the penis is not required for these to take place.
The shaft of the penis consists of two erectile bodies, called
the corpus cavernosum, These begin at the pelvic bone, extending to
just below the head of the penis. These spongy tissues are made up
of smooth muscle and blood vessels. The male hormone testosterone,
which is secreted by the testicles, controls the function of the
penis and a man's sex drive.
1 Because psychological or physical stimulation, the brain sends
a massage via the nervous system to the penis.
2 This message relaxes the smooth muscles in the blood vessel
walls of the corpus cavernosum, which causes them to open
wider.
3 as a result of this increased blood flows through the vessels,
causing the corpus cavernosum to fill.
4 while all of this is happening the veins that carry blood away
from the penis close. This in turn causes an increase in blood
pressure in the penis.
5 Blood that is held within the corpus cavernosum causes the
penis to become hard and erect.
