Transcript Your Body’s Reproductive System

Your Body’s
Reproductive System
Chapter 19
Reaches maturity during early teen years
 The testes begin to produce testosterone
(male sex hormone)
 Testosterone initiates physical changes
such as broadening of shoulders,
development of muscles, facial and other
body hair, and deepening of the voice.
 Testosterone also causes the production of
sperm (male reproductive cells)
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The Male Reproductive System
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Testes: also known as testicles
◦ Two small glands that produce sperm
◦ 100 million a day
◦ Hang outside of the body in a sac called the
scrotum
◦ The scrotum protects sperm by keeping the
testes at a temp below normal body temp.
◦ Tight clothing around testes can interfere with
sperm production.
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Penis: a tube shaped organ attached to
the trunk of the body just above the
testes.
◦ Composed of spongy tissue with many blood
vessels
◦ With increased blood flow, the penis becomes
enlarged and erect
◦ Erections can happen due to friction of
clothing, for not reason at all, or because of
sexual arousal
External Male Reproductive
Organs
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At the height of sexual arousal, a series of
muscular contractions known as ejaculation
may occur.
During ejaculation, semen-a thick fluid
containing sperm and other secretions- is
propelled from the penis.
If this happens during sexual intercourse,
fertilization may be initiated.
Fertilization is the union of a reproductive
cell from a male and one from a female.
Circumcision – surgical removal of the
foreskin covering the tip of the penis
 This is usually a parental decision that
happens at the birth.
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External Male Reproductive
Organs
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Urethra – moves liquid waste
Epididymis – large coiled tube connected to
the tubes in the testes. It is a temporary
storage facility for sperm. Sperm mature
here.
Vas deferens – pair of connecting tubes that
lead to the seminal vesicles and the prostate
gland.
Thick muscular walls of the vas deferens
propel sperm forward then it is combined
with a fluid produced by the seminal vesicles.
Internal Male Reproductive
Organs
This fluid contains nutrients and mixes
with the sperm to make it more mobile.
 Vas deferens and seminal vesicles meet to
form the ejaculatory duct.
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As the sperm continues to travel, it is
then mixed with fluid from the prostate
gland (small gland that surrounds the
urethra) and fluid from the Cowper’s
glands (located below the prostate gland).
 Semen is now formed.
 Semen and urine leave the body via the
urethra.
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Cleanliness
◦ Shower daily
◦ Clean the penis and scrotum
◦ Uncircumcised males must practice extra hygiene
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Protection
◦ Wear a protector or supporter during strenuous
activity to help shield the groin
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Self-examination
◦ Monthly to check for signs of cancer
◦ Lumps, thickenings, or change in texture or size of
testes
Care of the Male Reproductive
System
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STDs
Inguinal hernia – near the top of the
scrotum – sometimes the abdomen can tear
and part of the intestine pushed through.
Surgery is necessary.
Sterility – inability to reproduce
Enlarged prostate gland – caused by
infections, old age, or tumors
Prostate cancer – 2nd highest incidence of
cancer in males
Cancer of the testes – occurs frequently in
males 15-35 in the U.S. First sign is slight
enlargement of one testicle.
Problems
Ova – female reproductive cells
 Sperm enters through the vagina- a
muscular, elastic passageway that
extends from the uterus to the outside of
the body
 Ova are stored in the ovaries- the female
sex gland
 The two ovaries are located in the lower
abdominal area
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The Female Reproductive System
Ovulation – process of releasing one
mature ovum each month
 When a mature ovum is released, it
moves into the fallopian tubes- pair of
tubes with fingerlike projections that draw
the ovum in.
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Fertilization occurs in the fallopian tubes
 Zygote – cell that results from the union
of an ovum and sperm
 Uterus – small, pear-shaped, muscular
organ where the zygote travels to and
attaches itself
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If the ovum does not become fertilized then the
lining of the uterus breaks down into blood,
tissue, and fluids which pass through the cervixneck of the uterus
Menstrual flow happens once a month and lasts
3-5 days
After the menstrual cycle ends, the process
begins again. The uterus lining thickens again
preparing for the possibility of receiving a
fertilized egg.
Most females start between the ages of 10 and
15
The menstrual cycle may be irregular at first
Poor nutrition, stress, and illness can affect the
cycle
Menstruation
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Cleanliness
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Vagina is a self-cleansing organ
Slight vaginal discharge is normal
Especially important during menstrual cycle
Sanitary napkins (pads) and tampons must be
changed every few hours
◦ Breast examinations are important
◦ Should be done once a month
◦ In the shower, in front of a mirror, or lying
down
Care of the Female Reproductive
System
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Menstrual Cramps – abdominal cramps
Premenstrual Syndrome (PMS) – several
days to 2 weeks before the menstrual period
◦ Nervous tension, mood swings, irritability, anxiety,
depression, fatigue, etc
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Toxic Shock Syndrome (TSS) – rare but
serious disease that may be fatal
◦ Presence of the bacterium Staphylococcus aureus
◦ Signs include aching muscles, bloodshot eyes, sore
throat, fever, vomiting, rash, etc
Problems
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Blocked Fallopian Tubes – leading cause of
infertility
Endometriosis – uterine tissue grows
outside of the uterus
Pelvic Inflammatory Disease – infection of
the fallopian tubes, ovaries and surrounding
areas. Usually caused by STDs
Ovarian cysts – fluid-filled sac on the ovary
Cervical cancer – early sexual activity and
family history are related to an increased
incidence of cervical cancer
◦ Pap tests help detect
Problems That Can Cause
Infertility