Download Male Sexual Anatomy and Physiology

Male Sexual Anatomy and
Physiology
Lucy Capuano Brewer, Psychology
Psy 25 – Chapter 5
External Male Sexual
Anatomy
and Physiology
• Penis
• Scrotum
Penis
• The tube shaped organ that
swells with blood during sexual
arousal.
• The penis is composed of 3
sections:
• The root, (base) which anchors
penis within the body
• The shaft, which is the main
portion of penis existing outside
the body
• The glans penis (the head), a
blunt or conical highly sensitive
widened tip.
• The tissue that swells during an
erection consists of 3 cylinders...
• 2 of which are called the corpus
cavernosum on the top
• 1 of which is called the corpus
spongiosum on the underside
Corpus Cavernosa
Corpus Spongiosum
Foreskin
• All males are born with a foreskin.
• A foreskin is a loose collection of
skin that surrounds the glans.
• This skin attaches to the shaft of the
penis just proximal to the head.
• When the penis is flaccid, this
foreskin extends over the glans.
• When the penis is erect the glans
protrudes from the foreskin.
Male Circumcision
• During a circumcision, the prepuce of the foreskin,
which is the skin that covers the tip of the penis, is
removed.
• Circumcision is usually performed on the first or
second day after birth.
• It becomes more complicated and riskier in infants
older than 2 months and in boys and men.
• The procedure takes only about 5 to 10 minutes.
• A local anesthetic (numbing medicine) can be given
to your baby to lessen the pain from the procedure.
• Studies about the benefits of circumcision have
provided conflicting results
• The American Pediatric Association stands
neutral in this subject
Scrotum
• Pouch containing testes
• Active sperm require a temperature of about 93.6 F
• That's 5 degrees below normal body temperature.
• To provide this environment, muscles in the scrotum
regulate the temperature of the testes by pulling them
closer to the body for warmth or letting them hang
further from the body for cooling.
• The left teste usually hangs slightly lower than the right
in order to prevent uncomfortable collisions between
the testes while walking.
• The testes are also drawn close to the body during sex.
Penis Enlargement
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Nonsurgical methods of penis enlargement
NOTE** The Food and Drug Administration, the government
agency that regulates medications and medical devices, has
never approved any medications or devices for enlarging a
penis.
There are four basic types of nonsurgical penis enlargement:
Manual stretching or squeezing.
These exercises are supposed to be performed 30 minutes a
day for an indefinite period of time. Although they may be
safer than other methods, they can lead to scar formation, pain
and disfigurement.
Stretching with penile weights.
This technique is very likely to cause permanent penile
damage.
Vacuum pumps.
Because pumps draw blood into the penis and make it swell,
they're useful in the treatment of impotence (erectile
dysfunction). This may create an illusion of a larger penis, but
results are seldom permanent. Repeated use can damage
elastic tissue in the penis, leading to less-firm erections.
Pills and lotions.
These usually contain vitamins, minerals, herbs or hormones
such as testosterone; there's no evidence that it or any other
substance can increase penis size in adult men.
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Surgical methods of penis enlargement
Cosmetic surgeons have developed several
different enlargement techniques, none of them
endorsed by medical organizations - all issued
policy statements against cosmetic surgical
procedures to enhance the penis.
To lengthen a penis, surgery typically involves
snipping the suspensory ligament that attaches
the penis to the pubic bone and moving skin from
the abdomen to the penile shaft. The suspensory
ligament stabilizes and gives an upward tilt to an
erect penis.
When this ligament is cut, the penis may look
longer because more of it hangs outside the body.
But cutting the suspensory ligament can cause an
erect penis to wobble and position itself at odd
angles, particularly when erect.
Surgery to make the penis thicker involves
suctioning fat from a fleshy part of the body and
injecting the fat into the penis. Another technique
is simply to graft fat cut away from the buttocks or
abdomen
onto
the
penile
shaft.
Some
practitioners use tissue from cadavers.
None of these techniques have been shown to be
safe or effective.
The cost: about $10,000 for a typical penisenlargement surgery. Not covered by insurance
(Cosmetic)
Internal Male Sexual Organs
Internal Male Sexual Organs
• Include:
• the testes, the epididymis,
the
vas
deferens,
the
seminal
vesicles,
the
prostate gland, and the
Cowper’s glands.
• The testes, (To Testify) the
paired, oval-shaped organs
that produce sperm and
male sex hormones, are
located in the scrotum.
• They are highly innervated
and sensitive to touch and
pressure.
• The
testes
produce
testosterone,
which
is
responsible
for
the
development of male sexual
characteristics and sex drive
(libido).
• The epididymis are the
two highly coiled tubes
against the back side of
the testes where sperm
mature and are stored
until they are released
during ejaculation.
• The Vas Deferens are
the paired tubes that
carry the mature sperm
from the epididimys to
the urethra.
• The seminal vesicles are
a pair of glandular sacs
that secrete about 60%
of the fluid that makes
up the semen in which
sperm are transported.
Seminal fluid provides
nourishment for sperm.
• The prostate gland is a
walnut-sized,
glandular
structure that secretes
about 30% of the fluid
that makes up semen.
The prostate gland is
very
sensitive
to
stimulation and can be a
source of sexual pleasure
for some men.
• The Cowper’s glands are
two pea-sized glands at
the base of the penis
under the prostate gland
that secrete a clear
alkaline fluid into the
urethra during sexual
arousal
and
before
orgasm and ejaculation.
These glands produce
pre-ejaculatory fluid in
the urethra that acts as a
lubricant for the sperm
and coats the urethra as
semen flows out of the
penis (PRECUM)
Semen
• The whitish fluid expelled through the
opening of the penis (urethra) during
ejaculation.
• Most of the ejaculate is made up of the fluid
that supports the sperm.
• Besides sperm, (1%) semen is made up of
fluids; 65% from the seminal vesicles, 30 to
35% from the prostate and 5% from the vasa.
• The amount of ejaculate you produce can
vary, from just a few drops to about a
teaspoon full (2 to 6 ml).
• One amount of ejaculate may contain
between 40 million to 600 million sperm
depending on the volume and the length of
time stored before ejaculating.
• Yet, the quantity of sperm produced will only
cover the head of a pin.
Journey of the Sperm
interstitial
cellstestosterone
Journey of the Sperm
sperm
production
in the
seminferous
tubules
Journey of the Sperm
sperm
storage
in the
epididymis
ourney of the Sperm
transport
in the
vas
deferens
ourney of the Sperm
ampulla storage
Journey of the Sperm
ejaculatory
duct
fluid from
the
seminal
vessicles
Journey of the Sperm
fluid from
the
prostate
gland
ourney of the Sperm
cowper’s
gland
Journey of the Sperm
ejaculation
Erectile and Ejaculatory
Abnormalities
Peyronie’s disease:
• An abnormal condition
characterized by an
excessive curvature of
the penis that can make
erection quite painful
• Etiology: buildup of
fibrous tissue in the
penile shaft.
• It usually requires
medical attention.
Phimosis
• Phimosis is a medical condition in which
the foreskin of the penis of an
uncircumcised male cannot be fully
retracted.
• The word derives from the Greek phimos
("muzzle").
• In the United States, circumcision is the
surgical treatment of choice for
correction of phimosis
Retrograde ejaculation:
• Ejaculation in which the
ejaculate empties into
the bladder.
• The external sphincter
remains
closed

preventing the expulsion
of the seminal fluid; the
internal
sphincter
remains open  allowing
the ejaculate to empty
into the bladder.
• The result is a dry
orgasm.
• Etiology:
possible
(earlier
types
of
)
prostate
surgery,
tranquilizers, illness, and
accidents.
• Harmless  discharged
with urine.
• Infertility may be the
result.
Priapism:
• Painful erections that persist for hours or
days.
• Etiology: mechanisms that drain the blood
that erects the penis are damaged and so
cannot return the blood to the circulatory
system.
• Caused
by
the
following
medical
conditions: leukemia, sickle cell anemia, or
diseases of the spinal cord.
• Treatment: may become a medical
emergency, since prolonged erections
beyond six hours can starve the penile
tissues of oxygen, leading to permanent
tissue deterioration.
• Surgery or drugs are sometimes used.
Testicular Cancer
•
Cancer of the testicles is fairly uncommon,
affecting about 7,000 men a year in the United
States.
Risk factors for testicular cancer include:
• Age: testicular cancer is most common in
adolescents and young adults up to age 40. It is
the most common form of cancer in young men.
• Family history: if a man has testicular cancer,
his male relatives are at increased risk.
• Cryptorchidism: a condition in which one or
both of the testicles fail to descend from the
abdomen into the scrotum during infancy.
• Prior cancer history: a man who has had cancer
in one testicle has a higher risk of getting it in
the remaining testicle than someone who's
never had testicular cancer.
Symptoms
• Men are usually the first to find testicular
tumors, during a bath or other hygiene ritual.
Monthly self-examination of the testicles is
recommended for all men, particularly those
with one or more risk factors. Symptoms may
include:
• A painless lump on the testicle
• A heavy feeling in the scrotum
• A testicle that looks enlarged or feels different
Self Exam for Testicular Cancer
A testicular self exam is best performed after a
warm bath or shower. Heat relaxes the scrotum,
making it easier to spot anything abnormal.
The National Cancer Institute recommends
following these steps every month:
• Stand in front of a mirror.
• Check for any swelling on the scrotum skin.
• Examine each testicle with both hands.
• Place the index and middle fingers under the
testicle with the thumbs placed on top.
• Roll the testicle gently between the thumbs and
fingers.
• Don't be alarmed if one testicle seems slightly
larger than the other. That's normal.
Find the epididymis, the soft, tubelike structure
behind the testicle that collects and carries
sperm. If you are familiar with this structure,
you won't mistake it for a suspicious lump.
• Cancerous lumps usually are found on the
sides of the testicle but can also show up on
the front.
•
•
If you find a lump, see a doctor right away.
The abnormality may not be cancer, but if it is,
the chances are great it can spread if not
stopped by treatment.
Only a physician can make a positive
diagnosis.
Prostate Cancer
The Facts*
• About 70% of all diagnosed cancers: men aged 65
years
or
older.
Over the past 20 years, the survival rate increased
from 67% to 97%.
Studies have found the following risk factors for prostate
cancer:
• Age: Age is the main risk factor for prostate cancer.
This disease is rare in men younger than 45. The
chance of getting it goes up sharply as a man gets
older.
• Family history: A man's risk is higher if there is family
history
• Race: Prostate cancer is more common in African
American
• Diet: Some studies suggest that men who eat a diet
high in animal fat or meat may be at increased risk for
prostate cancer.
Screening:
• Digital Rectal Exam: The doctor inserts a lubricated,
gloved finger into the rectum and feels the prostate
through the rectal wall. The prostate is checked for
hard or lumpy areas.
• Blood test for PSA: A lab checks the level of PSA in a
man's blood sample. Prostate cancer may also cause a
high PSA level.
• The digital rectal exam and PSA test can detect a
problem in the prostate. They cannot show whether the
problem is cancer or a less serious condition.
Symptoms
• A man with prostate cancer may not have any
symptoms. For men who have symptoms of
prostate cancer, common symptoms include:
• Urinary problems
– Not being able to urinate
– Having a hard time starting or stopping the
urine flow
– Needing to urinate often, especially at night
– Weak flow of urine
– Urine flow that starts and stops
– Pain or burning during urination
• Difficulty having an erection
• Blood in the urine or semen
• Frequent pain in the lower back, hips, or upper
thighs
• Sometimes symptoms are not due to cancer.
Enlarged Prostrate
An enlarged prostate means the gland has
grown
bigger. Prostate enlargement happens to
almost
all men as they get older. As the gland
grows, it
can
press
on
the
urethra
and
cause urination and bladder
Symptoms
• Slowed or delayed flow of urine
• Weak urine stream
• Dribbling after urinating
• Straining to urinate
• Strong and sudden need to urinate
• Incomplete emptying of your bladder
• Incontinence
• Pain and bloody urine