Download Male/Female Notes - Oceanside Moodle

Human Reproduction
Male and Female
Reproductive System
Male Reproductive System
• Functions:
– To produce
sperm
– To deposit
the sperm into
the vagina
Structures of the Male
• Testes- 2 located in the
scrotal sac (Male
Gonad)
– Sperm are produced
in the seminiferous
tubules located in the
testes.
– This is where
gametogenesis and
meiosis take place
Scrotum
• Scrotum- sac like
structure that encloses
the testes.
• Helps keep temperature
2-4 degrees lower than
body temp.
• Important so sperm can
develop
Epididymis
• Located above the
testis
• Temporary storage
site for sperm
• Sperm mature here
Vas Deferens
• Tube that is attached to the epididymis, it carries
sperm out of the body
• As sperm travels through this tube, fluids
(sugars and proteins) are released from glands
These glands include: Prostate,
Seminal Vesicle and the Cowper’s gland
Sperm and fluids combine to make semen
Urethra
• Located inside the penis
• Removes semen and urine from the
body
Penis
• Muscular structure that deposits semen
into the female reproductive system
– Ejaculation- Semen is released from the
penis through muscle contractions
– Pathway sperm travels:
• Testes-Epididymis-Vas Deferens-Urethra-Penis
Frontal and Side View of Male
Female Reproductive System
• Functions:
– Provide a
pathway for
sperm to reach
the egg
– Provide a home
for a developing
embryo
Structures
• Ovaries- (Female
Gonad) there is a pair
of 2
– Production of eggs
(ovum) occurs here
– All eggs are present at
birth
– 200,000 eggs per ovary
• Follicles- Sacs located in the ovary and
help the egg mature
• Oviduct/Fallopian Tube- Tube like
structure attached to the ovary
– The egg is released into this structure
– FERTILIZATION TAKES PLACE HERE AND
ONLY HERE!!!!!
Uterus- Pear shaped muscular organ
– Implantation (attachment) of fertilized egg
occurs here
– It is where the baby develops
Cervix- Narrow muscular opening at the base
of the uterus
• Dilates during birth to 10cm to allow the baby to
come through the birth canal
Vagina- also known as the birth canal and
receives sperm
Frontal and Side View of
Female
The Menstrual Cycle
• There are 4 stages of the
menstrual cycle
• Usually last 28 days (varies in
females)
– The four stages are:
•
•
•
•
The Follicle Stage – egg is maturing
Ovulation- follicle releases the egg
Corpus Luteum- Broken follicle fills in
Menstruation- Release of all mucus and
blood
Follicle Stage
• Last between 10-14 days
• FSH (follicle stimulating hormone) is
released by the pituitary gland.
This hormone helps the follicle mature
• Estrogen is also released from the ovary
to build the uterine lining with blood
vessels and mucus to prepare for
pregnancy
Ovulation
• The 2nd stage of the cycle
• Takes place around day 14.
– The pituitary gland realizes there is too
much estrogen in the blood
– It stops releasing FSH and starts to release
LH (lutenizing hormone)
This is FEEDBACK
The high levels of LH in the blood cause a
follicle to rupture and to release the egg
into the fallopian tube
Corpus Luteum Stage
• Lasts about 10-14 days
– LH causes the broken follicle to fill with a
yellow body of cells called the corpus
luteum.
– The Corpus Luteum in the ovary secretes
progesterone which further builds the
uterine lining for a possible pregnancy.
Menstruation
• Last stage of the cycle lasts 3-5
• Takes place if fertilization does not
occur
• If fertilization does not occur then
progesterone stops being released and
the uterus lining breaks down.
• All that has built up and the egg is
released
• The menstrual cycle is an
example of a feedback
mechanism.
• They help maintain
homeostasis
• This is what women feel
like at each stage
Development
• If fertilization
occurs the embryo
implants in the
uterus.
• The embryo begins
its life journey
Cleavage
• The first set of mitotic cell divisions that
the zygote undergoes.
• It takes place in the oviduct.
• These cells are unspecialized (have no
job)
• The zygote divides in 2, then 4 then 8 then
16 etc.
Morula
• Mitosis creates a
solid ball of cells
called a Morula
Blastula
• Cells continue to
divide into a
“hollow” sphere.
Gastrula
• The gastrula
forms through
gastrulation.
• The cells in this
step push
inward and form
a 2-layered cell.
development
Differentiation
• The process when “unspecialized cells
become specialized”
• They begin to have a job
• DNA controls what cells do what job
• Three layers form in differentiation
Ectoderm
• Forms the outer layer
• Becomes the Nervous System
• Lining of the mouth, anus, and nostrils
• Skin, Sweat gland, Hair and Nails
Mesoderm
• Middle Layer
• Forms bones and muscle
• Blood and Vessels
• Reproductive and Excretory System
Endoderm
• Inner Layer
• Forms the lining of digestive system
• Lining of the respiratory system
• Forms bladder, liver, pancreas and
thyroid gland
Implantation and Development of
Fetus
• Implantation occurs
5-10 days after
fertilization
Structures the fetus needs
• Placenta- Forms
around the fetus
• Baby gets all its
nourishment from
this structure
• Helps with food and
gas exchange
• Chorionic Villi- help increase the surface
area for absorption of nutrients and
gases across the membrane
• Umbilical Cord- connection between the
baby and the placenta.
• Contains veins and arteries to help the
baby get materials that move through the
placenta
• Remember the blood of
the mom and baby do not
mix.
• Amniotic Fluid– Surrounds the placenta
– Absorbs shock
– They use this fluid to
perform an
amniocentesis. (genetic
tests)
Birth
• Occurs after 9 months
• Cervix dilates (10 cm), amniotic
membrane bursts (water break)
• Labor Begins
Twins
• Fraternal- two eggs
and two sperm
• Identical- one
egg/one sperm and
the zygote splits in
two.