Reproductive
System
AP Biology
Reproductive hormones

Testosterone



from testes
sperm
production & sex
characteristics
Estrogen


from ovaries
egg production,
preparing uterus
for fertilized egg
& sex
characteristics
Regents Biology
Male
reproductive
system

Sperm production
over 100 million produced per day!
Regents 
Biology
~2.5 million released per drop!

seminiferous
tubule
sperm
spermatocytes
Regents Biology
Male reproductive system

Testes & epididymis


Glands


Regents Biology
sperm production &
maturation
seminal vesicles,
prostate,
bulbourethal
(Cooper’s Gland)
produce white
seminal fluidnutrient-rich
Male reproductive system

Testicles


Scrotum


where sperm mature- 18 hrs
Vas Deferens


sac that holds testicles outside of bodymaintains lower temperature
Epididymis


produces sperm & hormones
tubes for sperm to travel from testes to penis
Prostate, seminal vesicles,
Cowper’s (bulbourethal) glands

nutrient rich fluid to feed & protect sperm
Regents Biology
Testis and Spermatogenesis
Regents Biology

Spermatozoa

Head contains
nucleuscontains
enzymes that
help the sperm
enter the egg.


Regents Biology
body and tail
allow movement
Mitochondriaprovides ATP
for movement
Female reproductive system
Regents Biology
Female reproductive system





Ovaries- have 2
 produces eggs & hormones- estrogen & progesterone
Uterus
 Site for fetal development, nurtures fetus; lining builds up
each month- menstruation- shedding of the lining of the
uterus.
Fallopian tubes- 2
 tubes for eggs to travel from ovaries to uterus
 Fertilization occurs in the fallopian tubes
Cervix
 (separates vagina from uterus) opening to uterus, dilates 10
cm for birthing baby
Vagina
 birth canal for birthing baby
Regents Biology
Female reproductive system
Regents Biology
Egg maturation in ovary
releases
progesterone
maintains
uterus
lining
produces
estrogen
Regents Biology
LH
Menstrual cycle

Controlled by
interaction of
4 hormones egg development
FSH & LH
 estrogen
 progesterone
FSH
ovulation = egg release

corpus luteum
estrogen
progesterone
lining of uterus
Regents Biology
days0
7
14
21
28
Feedback
Female reproductive cycle
egg
matures &
is released
(ovulation)
estrogen
builds up
uterus lining
corpus
luteum
ovary
progesterone
FSH & LH
maintains
uterus lining
fertilized egg
(zygote)
HCG
yes
pituitary
gland
pregnancy
GnRH
Regents Biology
hypothalamus
no
corpus luteum breaks down
progesterone drops
menstruation
corpus
luteum
progesterone
maintains
uterus lining
Female hormones

FSH & LH



Estrogen



stimulates egg development & hormone release
peak release = release of egg (ovulation)
stimulates growth of lining of uterus
decreasing levels causes menstruation
Progesterone


stimulates blood supply to lining of uterus
decreasing levels causes menstruation
Regents Biology
Fertilization
Regents Biology
Fertilization- process
where sperm enters
and fertilizes egg
(ovum)- resulting in
the formation of a
zygote
Regents Biology
Sex Determination in Mammals
Regents Biology
Twins

Identical TwinsONE fertilization

Zygote splits into
two with each
being identical to
one another
Regents Biology
Fraternal Twins- TWO fertilizations
Two different zygotes (different egg and
sperm)
Regents Biology
Siamese
Twins- identical twins whose bodies fail to fully
separate- and stay joined together
Regents Biology
Regents Biology
Placenta & umbilical cord


Allows for nutrients and gases to be exchanged
between mom and child
Food & gases diffuse across blood vessels
Regents Biology
Human fetal development
4 weeks
Regents Biology
7 weeks
Human fetal development
10 weeks
Regents Biology
Human fetal development
12
weeks
Regents
Biology
20 weeks
Human fetal development

The fetus just spends much of the 2nd &
3rd trimesters just growing
…and doing various flip-turns & kicks
inside amniotic fluid
Week 20
Regents Biology
Human fetal development

24 weeks (6 months; 2nd trimester)
fetus is covered
with fine, downy
hair called
lanugo. Its skin
is protected by
a waxy material
called vernix
Regents Biology
Human fetal development

30 weeks (7.5 months)
umbilical cord
Regents Biology
Getting crowded in there!!

32 weeks (8 months)
The fetus
sleeps 90-95%
of the day &
sometimes
experiences
REM sleep, an
indication of
dreaming
Regents Biology
positive feedback
Birth
Regents Biology
Birth (36 weeks)
Intestine
Placenta
Umbilical
cord
Wall of
uterus
Bladder
Cervix
Vagina
Regents
Biology
The end of the journey!
And you think
9 months of
Biology is hard!
Regents Biology
Harmful Environmental Factors

Embryo’s inherited genes can cause diseases



Mutations- changes in DNA (DNA makes up
chromosomes)
Mother’s exposure to harmful environmental factors
such as DRUGS, POOR DIET, ALCOHOL, TOBACCO
can cause developmental problems and learning
disabilities
Sexually Transmitted Diseases (STDs)- diseases
passed on from person to person through sexual
contact

AIDS, Chlamydia, Syphilis
Regents Biology
Let’s Practice!
1. Which statement about the gametes
represented in the diagram below is
correct?
1.
2.
3.
4.
They are produced by females.
They are fertilized in an ovary.
They transport genetic material.
They are produced by mitosis.
Regents Biology
Let’s Practice!
1. Which statement about the gametes
represented in the diagram below is
correct?
1.
2.
3.
They transport genetic material.
4.
Regents Biology
1.
2.
3.
4.
2. Base your answer on your knowledge of biology
and on the diagrams. Testosterone is produced by
structure A
structure B
structure C
structure D
Regents Biology
2. Base your answer on your knowledge of biology
and on the diagrams. Testosterone is produced by
1.
2.
3.
structure C
4.
Regents Biology
3. Base your answer to this question on the diagram
below, which represents some stages in the
development of an embryo, and on your knowledge of
biology. The arrow labeled X represents the process
of
1.
2.
3.
4.
meiosis
recombination
differentiation
cloning
Regents Biology
3. Base your answer to this question on the diagram
below, which represents some stages in the
development of an embryo, and on your knowledge of
biology. The arrow labeled X represents the process
of
1.
meiosis
2.
3.
4.
Regents Biology
1.
2.
3.
4.
4. Base your answer on the diagram
and your knowledge of biology.
Gamete cells are produced within
structures A and J
structures E and G
structures B and I
structures D and H
Regents Biology
4. Base your answer on the diagram
and your knowledge of biology.
Gamete cells are produced within
1.
2.
structures E and G
3.
4.
Regents Biology
1.
2.
3.
4.
5. The diagram represents some stages
in the development of an embryo. Which
stage represents a zygote?
stage A
stage B
stage C
stage D
Regents Biology
1.
5. The diagram represents some stages
in the development of an embryo. Which
stage represents a zygote?
stage A
2.
3.
4.
Regents Biology
6. The primary function of
structure X is to
1.
2.
3.
4.
produce energy needed
for sperm to move
provide food for the
sperm to carry to the
egg
produce and store urine
form gametes that may
be involved in
fertilization
Regents Biology
6. The primary function of
structure X is to
1.
2.
3.
4.
form gametes that may
be involved in
fertilization
Regents Biology
7. Although all the body cells in an animal
contain the same hereditary information,
they do not all look and function the same
way. The cause of this difference is that
during differentiation
1.
2.
3.
4.
embryonic cells use different portions of
their genetic information
the number of genes increases as embryonic
cells move to new locations
embryonic cells delete portions of the
chromosomes
genes in embryonic cells mutate rapidly
Regents Biology
7. Although all the body cells in an animal
contain the same hereditary information,
they do not all look and function the same
way. The cause of this difference is that
during differentiation
1.
embryonic cells use different portions of
their genetic information
2.
3.
4.
Regents Biology
8. Which hormone has the lowest concentration on
which day?
1.
2.
3.
4.
hormone A on day 4
hormone B on day 2
hormone C on day 12
hormone D on day 20
Regents Biology
8. Which hormone has the lowest concentration on
which day?
1.
2.
hormone B on day 2
3.
4.
Regents Biology
1.
2.
3.
4.
9. During which
five-week period
did the fetal mass
increase at the
greatest rate?
weeks 10–15
weeks 15–20
weeks 25–30
weeks 30–35
Regents Biology
9. During which
five-week period
did the fetal mass
increase at the
greatest rate?
1.
2.
3.
4.
weeks 30–35
Regents Biology
10. Human egg cells are most similar
to human sperm cells in their
1.
2.
3.
4.
degree of motility
amount of stored food
chromosome number
shape and size
Regents Biology
10. Human egg cells are most similar
to human sperm cells in their
1.
2.
3.
chromosome number
4.
Regents Biology
11. The process of meiosis formed
1.
2.
3.
4.
cell 1, only
cells 1 and 2
cell 3, only
cells 2 and 3
Regents Biology
11. The process of meiosis formed
1.
2.
cells 1 and 2
3.
4.
Regents Biology
12. Heavy cigarette smoking and the use of
alcohol throughout pregnancy usually
increase the likelihood of
1.
2.
3.
4.
the birth of twins
the birth of a male baby
a baby being born with a viral infection
a baby being born with medical problems
Regents Biology
12. Heavy cigarette smoking and the use of
alcohol throughout pregnancy usually
increase the likelihood of
1.
2.
3.
4.
a baby being born with medical problems
Regents Biology
13. A large number of sperm cells are produced by
males every day. This large number of sperm cells
increases the chance that
1.
2.
3.
4.
at least one sperm cell will be reached when the eggs
swim toward the sperm cells in the ovary
several sperm cells will unite with an egg so the
fertilized egg will develop properly
some of the sperm cells will survive to reach the egg
enough sperm cells will be present to transport the egg
from where it is produced to where it develops into a
fetus
Regents Biology
13. A large number of sperm cells are produced by
males every day. This large number of sperm cells
increases the chance that
1.
2.
3.
some of the sperm cells will survive to reach the egg
4.
Regents Biology
14. In 1993, there were only 30 panthers in Florida. They
were all closely related and many had reproductive
problems. To avoid extinction and restore health to the
population, biologists introduced 8 female panthers
from Texas. Today, there are more than 80 panthers in
Florida and most individuals have healthy reproductive
systems. The success of this program was most likely
due to the fact that the introduced females
1.
2.
3.
4.
produced more reproductive cells than the male
panthers in Texas
solved the reproductive problems of the species by
asexual methods
increased the genetic variability of the panther
population in Florida
mated only with panthers from Texas
Regents Biology
14. In 1993, there were only 30 panthers in Florida. They
were all closely related and many had reproductive
problems. To avoid extinction and restore health to the
population, biologists introduced 8 female panthers
from Texas. Today, there are more than 80 panthers in
Florida and most individuals have healthy reproductive
systems. The success of this program was most likely
due to the fact that the introduced females
1.
2.
3.
increased the genetic variability of the panther
population in Florida
4.
Regents Biology
1.
2.
3.
4.
15. Exposure to radiation or certain
chemicals could alter the genetic
information in the gametes that form
in structure
A
B
C
D
Regents Biology
15. Exposure to radiation or certain
chemicals could alter the genetic
information in the gametes that form
in structure
1.
2.
B
3.
4.
Regents Biology
16. Which event would most probably result
in the production of fraternal twins?
1.
2.
3.
4.
One egg is fertilized by two sperm cells.
Two egg cells are fertilized by one sperm
cell.
Two egg cells are each fertilized by separate
sperm cells.
Two eggs develop without fertilization.
Regents Biology
16. Which event would most probably result
in the production of fraternal twins?
1.
2.
3.
Two egg cells are each fertilized by separate
sperm cells.
4.
Regents Biology
17. Compared to human cells resulting
from mitotic cell division, human cells
resulting from meiotic cell division
would have
1.
2.
3.
4.
twice as many chromosomes
the same number of chromosomes
one-half the number of chromosomes
one-quarter as many chromosomes
Regents Biology
17. Compared to human cells resulting
from mitotic cell division, human cells
resulting from meiotic cell division
would have
1.
2.
3.
one-half the number of chromosomes
4.
Regents Biology
18. Which phrase best describes a process
represented in the diagram below?
1.
2.
3.
4.
a zygote dividing by mitosis
a zygote dividing by meiosis
a gamete dividing by mitosis
a gamete dividing by meiosis
Regents Biology
18. Which phrase best describes a process
represented in the diagram below?
1.
a zygote dividing by mitosis
2.
3.
4.
Regents Biology
19. A cell with a diploid chromosome
number of 12 divided two times, producing
four cells with six chromosomes each. The
process that produced these four cells was
most likely
1.
2.
3.
4.
internal fertilization
external fertilization
mitotic cell division
meiotic cell division
Regents Biology
19. A cell with a diploid chromosome
number of 12 divided two times, producing
four cells with six chromosomes each. The
process that produced these four cells was
most likely
1.
2.
3.
mitotic cell division
4.
Regents Biology
20. Which structure is
correctly paired with its
function?
1.
2.
3.
4.
A - releases estrogen
and progesterone
B - produces and
releases the egg
C - provides the usual
site for fertilization
D - nourishes a
developing embryo
Regents Biology
20. Which structure is
correctly paired with its
function?
1.
2.
B - produces and
releases the egg
3.
4.
Regents Biology