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Why does my cock grow when I see young men?
On 8 Nov 2005 04:49:13 -0800, wrote:
Is that "grow" or "crow"? :-)
An erection of the penis occurs when engorgement of venous blood in
two
tubular structures at the bottom of the penis, the corpora cavernosa,
results from a variety of stimuli. The corpus spongiosum is a single
tubular structure located just above the corpora carvernonosa, and
contains the male urethra, through which urine and semen pass during
urination and ejaculation, respectively. This may also become slightly
engorged with blood, but less so than the corpora cavernosa. Penile
erection usually results from sexual stimulation and/or arousal, but
can also occur by such causes as a full urinary bladder or
spontaneously, most commonly during erotic or wet dreams. An erection
results in swelling and enlargement of the penis or the swelling of
the
female counterpart to the penis, clitoris. Erection enables sexual
intercourse and other sexual activities, though it is not essential
for
all sexual activities.
In addition to sexual arousal, erection in males can be caused by
mechanical stimulation, or by the pressure of the filled urinary
bladder. Erections when waking up are common, most likely due to a
full
bladder. They sometimes already occur in infant boys, and in utero.
Physiologically, an erection is achieved by two mechanisms that play
together: increased inflow of blood into the vessels of erectile
tissue, and decreased outflow. The vessel system involved is known as
the corpara cavernosa and the corpus spongiosum. Muscles in the region
relax, allowing more blood to enter these sponge-like tissues.
Contraction of other muscles reduce the outflow. The enlarged
structure
then exerts pressures on the exit veins, further reducing the outflow.
As blood flows in, the penis stiffens, its girth and length increases,
and it rises to an angle that can vary from below horizontal to almost
vertical.
Certain conditions (e.g. diabetes mellitus) result in erectile
dysfunction, a problem where penile erection is insufficient to
achieve
normal sexual intercourse. In recent years, several drugs have been
developed for treatment of this condition.
If present, the foreskin normally retracts and exposes the glans. The
skin of the scrotum tightens, pulling the testicles in towards the
base
of the penis.
Erection is caused by signals from the parasympathetic nervous system;
it is countered by the sympathetic nervous system which is mainly
responsible for the "fight-or-flight" response. This explains why
under
stressful conditions, an erection is often difficult or impossible to
achieve, and sudden onset of stress can deprive one of erection. The
sympathetic nervous system is also responsible for causing
ejaculation,
which explains why most males lose their erection after ejaculation.
Erections may occur even after death, if the pressure within the penis
increases for some reason, for example due to sinking fluids or the
formation of gases of putrefaction. See death erection.
The clitoris of females also contains erectile tissue and may become
erect during sexual arousal; the erection of nipples, however, is not
due to erectile tissue.
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