Male Reproductive
System
What the Male Reproductive
System Does
 Main function is to produce sperm and
deliver it to the female reproductive
system
How the Male Reproductive
System Works
Male Puberty
 Starts at around age 12-13
 Hormonal changes stimulate an increase in
growth rate, alterations in behavior,
enlargement of the genitals, and the
appearance of secondary sexual
characteristics such as facial hair.
 Because boys begin their final growth spurt
later than girls, they have a longer period of
steady growth and usually attain a greater
adult height.
Male Puberty
 Changes that occur:
 Growth spurt occurs
 Acne may appear
 Larynx enlarges, voice
deepens
 Facial hair appears
 Shoulders broaden
 Underarm hair appears
 Perspiration increases
 Some breast enlargement
may occur
 Muscles develop
 Pubic hair appears
 External genitals enlarge
 Sperm production begins
 First ejaculation occurs
 Long bone growth stops
Sperm
 Sex cells that are
produced in the testes
and are used to
fertilize the egg
 Sperm swim at the
rate of 1-4mm per
minute or 60-240mm
per hour
 50,000 sperm are
produced each
MINUTE in mature
men
Testicles (testes)
 Male reproductive
organ that makes
sperm and
testerone
 Male begin
producing 100+
million sperm a
day once they
reach puberty
Seminiferous Tubules
 Tightly coiled tubes inside the testes
where sperm are made
Testosterone
 The male sex hormone that influences
sperm production
 During puberty, testosterone causes
facial and body hair to grow, shoulders to
broaden and voice to deepen
Scrotum
 The skin covered
sac that the testes
rest in
 Muscles of the
scrotum help with
temperature control
 Sperm develop best
several degrees
below 98.6
Penis
 The external male
reproductive organ that
is made up of spongy
tissue that has blood
flow going through it
 The penis removes
urine from the bladder
and also delivers sperm
to the female
reproductive system
 The glans is the
sensitive nerve ending
near the tip of the penis
Foreskin
 A piece of skin that partially covers the tip
of the penis at birth
 Circumcision is the
removal of the
foreskin from the tip
of the penis
Erection
 When the penis becomes hard and firm
 The blood vessels in the penis fill with
blood
 The penis must be erect in order for
ejaculation to occur
Ejaculation
 When sperm are released from the penis
 One ejaculation contains 40-300 million
sperm
 It is normal for a male to ejaculate during
sleep, this is called nocturnal emissions
or “wet dreams”
Urethra
 Urine passes
through the urethra,
a tube that starts at
the bladder and
ends at the opening
of the penis
 Sperm also pass
through the urethra
during ejaculation
but not at the same
time as urine is
carried
Epididymis
 A tightly coiled tube where sperm mature
as they pass through
 The epididymis can be up to 700 feet
long
Vas Deferens
 The next portion
of a hollow tube
that sperm pass
through
 The vas deferens
can be up to 12
inches long
Vasectomy
 The severing and tying off of the vas
deferens
 Once the vas deferens is severed, sperm
will not be able to be ejaculated out of the
penis
Seminal Vesicles
 Found near the base of the urinary bladder
 Produce thick secretions that nourish the
sperm and help sperm move easier
Prostate Gland
 Encircles the urethra near the bladder
 About the size of a walnut
 Secretes a thin, milky fluid that protects
the sperm from acid in the female
reproductive system
Cowper’s Gland
 Found near urethra
below the prostate
 Prior to ejaculation
this gland secretes
a clear fluid that
protects the sperm
from acid in the
male urethra
Bladder
 A triangular sac that stores urine before it
is excreted out of the body
Sphincter Valve
 A small piece of skin, a muscle that holds
back urine or semen so that both do not
come out of the body at the same time
Prostate Exam
 An examination that is performed to identify
any irregularities in the prostate
 Exams help in early detection of prostate
cancer
 Prostate cancer occurs primarily in older males
and is the 2nd most common cancer in males in
the U.S
 For every 3 men diagnosed with cancer this
year 1 will have prostate cancer.
Testicular Exam
 A self exam that men should perform
once per month once they have reached
puberty to detect any lumps, swelling,
pain, or discomfort in the scrotum or
abdomen
Path of Sperm
 Testes
 Epydidimis
 Vas deferens
 Prostate Gland
 Seminal Vesicle
 Sphincter Valve
 Urethra
 Ejaculated out of Body
Path of Sperm
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