BCLN BIOLOGY 12 – Rev July 2014
Unit 15 ~ Learning Guide
Name:________________
INSTRUCTIONS
Complete the following notes and questions as you work through the related lessons.
You are required to have this package completed BEFORE you write your unit test. Do
your best and ask questions about anything that you don't understand BEFORE you
write the unit test.
U15 NOTES: REPRODUCTIVE SYSTEMS (web notes)
Male Reproductive System
Testes (male gonads)







Produce _________________
Produce _______________________________
Found in a sac called the __________________
Suspended outside of the body cavity for
______________________________________
Testes wall made of fibrous connective tissue
(divides the testes into lobules/chambers)
inside chambers are long tubes (70cm) called
the
________________________________
This
is
the
actual
site
for
______________________________________.
Interstitial cells secretes androgens "_______________________"
Spermatogenesis: Sperm Development
Sperms cells are derived from
undifferentiated cells called
SPERMATOGONIA
(sing.
Spermatogonium), which lie
just on the outside wall of a
tubule and divide mitotically,
always
producing
new
spermatogonia.
Some
newly
formed
spermatogonia move away
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BCLN BIOLOGY 12 – Rev July 2014
from the outer wall to increase in size and become primary spermatocytes, which
undergo meiosis, a type of cell division.
Primary spermatocytes, with 46 chromosomes, divide to give 2 secondary
spermatocytes, each with 23 chromosomes.
Secondary spermatocytes divide to produce 4 spermatids, also with 23 chromosomes,
but each only having one chromatid.
Spermatids then differentiate into sperm (spermatozoa). Also present in the tubules are
the SERTOLI cells, which support, nourish and regulate the spermatogenic cells.
Male Reproductive Structures
Epididymis
 ____________________
____________________
___________________.
Seminal Vesicle
 ____________________
___________________.
Cowper's Gland
 Pea-sized organs that lie
posterior to the prostate
on either side of the
urethra.
 ____________________
___________________.
Prostate Gland
 A single dough-nut shaped gland that surrounds the upper portion of the urethra
just below the bladder.
 Older men can have their prostate become enlarged and urination becomes quite
painful (surgically fixed)
 ___________________________________________.
Urethra
 _____________________________________________________.
Ductus Vas Deferens
 ________________________________________________________________.
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BCLN BIOLOGY 12 – Rev July 2014
Penis
 ______________________________________________________.
Sperm Structure/Function
1.
2.
3.
4.
5.
Formed in the seminiferous tubules of the testes
Mature and stored in the epididymis
Stored in the Vas Deferens
Enters the urethra just prior to ejaculation
Accessory glands (prostate, Cowper's gland, and seminal vesicle) add secretions
to semen.
6. Semen and sperm exit through the penis
SOURCES:
1. Seminal Vesicle
2. Prostate Gland
3. Cowper's Gland
FUNCTION:
1. Produce basic fluid, pH 7.5 (slightly basic) is ideal for healthy sperm
and thus, a basic fluid is needed to _______________________
_______________________________________________________.
2. Provides ______________________________________ for sperm.
3. Contains ____________________________ - chemicals which cause
the uterus to contacts.
4. Aids in the _____________________________________ to the egg
(mucous)
5. ________________________
Parts of the Sperm
1. Head:
 contains 23 chromosomes
 ________________ attached = type of
_________________.
 contains __________________________.
 digests the ________________________
______________________________ so
sperm can penetrate.
2. Middle Piece:
 Contains mitochondria - ___________
________________
3. Tail: ____________________________________________
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BCLN BIOLOGY 12 – Rev July 2014
Function of Testosterone
1. Essential for development of
_______________________
_______________________
2. Essential for the development
of ____________.
 spermatogenic
cells
take up ____________
which stimulate their
activity.
3. Increase
testosterone
concentration
at
puberty
causes ________________
_______________________
_______________________
4. Secondary
sex
Characteristics
 facial hair
 _________________
 pubic hair
 oil and sweat
 gland secrete(=stinky)
 larynx expands (voice changes)
 increase muscular strength
 _____________________
 sex drive
 NOTE: Side effect is baldness
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if
genetically
predisposed
BCLN BIOLOGY 12 – Rev July 2014
Hormonal Control of Testosterone
Hypothalamus releases GnRH (______________
______________________________________)
GnRH causes anterior pituitary to release 2
gonadotropic hormones:
1. FSH (____________________________)
 promotes spermatogenesis in
the seminiferous tubules
2. LH (______________________________)
 promotes
production
of
testosterone in interstitial cells
NEGATIVE FEEDBACK
Increase testosterone concentration in the blood
causes the ____________________________ to
make
_______________
and
therefore,
__________ testosterone is produced.
Decrease testosterone concentration in the blood
causes the __________________________ to
make more LH and therefore, more testosterone is ____________________.
Increase concentration of stored sperm causes an increase in production of
____________________ and decreases production of FSH, therefore production of
sperm ______________________.
Decrease concentration of stored sperm causes a _____________________________
_______________________________________________ and more FSH, therefore
____________________ is produced
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BCLN BIOLOGY 12 – Rev July 2014
Female Reproductive Structures
Cervix
 Narrow end of uterus
leading to the vagina.
 dilates _______________
to allow baby to exit.
Clitoris
 female sensory organ;
homologous to the male
penis.
 provides sensitivity during
intercourse.
Labia major and Labia minor
 protective folds of skin.
Vestibule
 cleft between the labia
minor.
 contains opening (orifices)
to the urethra and vagina.
Fimbriae
 Finger-like projections of the _________________________________________
__________________________.
 along with cilia in the oviducts, they cause a _______________ which sweeps
the egg ___________________________________.
Oviduct
 conducts _________ towards the _______________________
 also called the _____________________________ or uterine tube.
Ovaries
 produce _________________________________________________________.
Uterus (Womb)
 ________________________________________________________________.
Vagina
 Receives
penis
during
sexual
_____________________________.
intercourse
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and
serves
as
a
BCLN BIOLOGY 12 – Rev July 2014
Functions of Estrogen
1. Stimulates growth of ___________
____________________________
__________________.
2. Egg maturation
3. Secondary Sex Characteristics:
 armpit hair/pubic hair
 ______________________
______________________
_____________________
 enlarged _______________
_____________ (wider hips)
 breast
development
(requires _______________
as well)
Ovarian Cycles
Day 1 -13 Follicular Phase
1. Hypothalamus produced a GnRH to stimulate ____________________________
_____________________________________.
2. FSH
and
LH
from
pituitary
gland
stimulates
________________________________________________________________.
3. Primary follicle (46 chromosomes) contains primary ________________ which
divides. (produced ___________________________) One oocyte get most
_______________________________________ (called a secondary oocyte,
which is inside the now secondary follicle).
4. Other oocyte called the _________________________ disintegrates.
5. The secondary follicle grows into a __________________ (vesicular) Follicle.
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BCLN BIOLOGY 12 – Rev July 2014
Day 14 Ovulation
6. Grafian Follicle __________ (ovulation) LH is at its highest and triggers
ovulation.
Day 17 - 28 Luteal Phase
7. The follicle has lost its oocyte (or "egg") and forms into ____________________
________________________________________________________________
 the corpus luteum ____________________________________________
 ___________________________________________________________
If pregnancy does not occur: _________________________________ breaks down
(about 10 days) If pregnancy does occur: Corpus Luteum remains for 3 - 6 months and
continues to produce _________________. Cycle will repeat.
Uterine Cycle
Day 1 - 5 Menstruation
1. Low levels of sex hormones (_____________________________________ has
just disintegrated).
2. ______________________________ (lining of Uterus) breaks down.
3. Cells of the endometrium, blood vessels, and blood are ____________________
_____________________________________ and exit the vagina.
4. A flow of blood (____________________________) passes out of the vagina
during a period called menstruation.
Day 6 - 10 Proliferative Phase
5. Increase ___________________________ by the ovarian follicle causes the
_________________________ to rebuild.
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BCLN BIOLOGY 12 – Rev July 2014
Day 14
6. ____________________________________________ (release of egg).
Day 15 - 28 Secretory Phase
7. Increase level of progesterone by the __________________________________.
8. Endometrium doubles in thickness and becomes highly vascularized.
9. Glands produce _______________.
10. Now prepared to receive embryo.
If no pregnancy. The corpus luteum degenerates, decrease in progesterone production
occurs
and
the
endometrium
breaks
down.
Cycles
continues.
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BCLN BIOLOGY 12 – Rev July 2014
Hormonal Control
FSH
 Hypothalamus
secretes
GnRH
(____________________
_____________________
____________________)
and causes the anterior
pituitary to secrete.
______ (days 1 - 13)
______ (days 14 - 28)

FSH causes ___________
_____________________
Maturing follicles produce
____________________

Increase
in
estrogen
concentration
____________________________
______________________________________________.
causes
Start of Day 1 – 13
 Increase FSH ______________________________________
 Decrease FSH _______________________________________
LH

LH is released _______________________






Large spike - day 14 – ovulation
(15 - 28) Causes the _____________________________________
Corpus luteum _______________________________
Increase in progesterone cause anterior pituitary gland to stop producing LH.
Day 15 - LH increases and progesterone _______________.
Day 28 - LH decreases and progesterone ________________.
YOU SHOULD CLICK ON THE LINK TO REVIEW THE FEMALE
REPRODUCTIVE SYSTEM BEFORE YOU PROCEED ANY FURTHER.
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the
BCLN BIOLOGY 12 – Rev July 2014
Oxytocin and Positive Feedback
Oxytocin ___________________________________. Contact of the fetal head with the
cervix stimulates the release of oxytocin. Oxytocin causes the uterus to contract and
contraction
of
the
uterus
causes
the
release
of
more
oxytocin.
Oxytocin also causes ______________________________________________.
Lobules containing milk contract forming milk into ducts which lead to the nipple.
Implantation






Implantation occurs in the ______.
Fertilization occurs in the _______.
Embryo embeds itself in the _____________ several days after fertilization.
Membrane surrounding the embryo produced a hormone called HCG
(________________________________________________). The Placenta
then develops. It is found immediately in blood and a few days later in the urine.
o HCG is the hormone detected by ________________________ (about
one week following implantation)
HCG prevents the breakdown of the _____________________________. The
Corpus
Luteum
produced
progesterone
that
keeps
the
_________________________ from breaking down.
FSH
and
LH
production
is
inhibited
which
________________________________________________________________.
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BCLN BIOLOGY 12 – Rev July 2014
Placenta
Contains both _____________________________________and is the area where
____________________________________________. There is no exchange of
_______________. Diffusion of gases and wastes and nutrients occur across the
_____________________________.
Placenta produces __________ which maintains the corpus luteum. The corpus luteum
continues to produce ______________________________, which prevents breakdown
of the _____________________, and estrogen which keeps new eggs from developing.
YOU SHOULD CLICK ON THE LINK TO
REVIEW AND COMPLETE THE REPRODUCTIVE
SYSTEM PROBLEM SET BEFORE YOU PROCEED ANY FURTHER.
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BCLN BIOLOGY 12 – Rev July 2014
U15 PRACTICE: REPRODUCTIVE SYSTEMS
1. Label the following diagram of the male reproductive system. Provide a brief
description of each structure's function below the diagram. Please be neat. (20
marks)
2. Why does sterility result if the testes do not descend into the scrotum? (2 marks)
3. What is spermatogenesis and where does it occur? (2 marks)
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BCLN BIOLOGY 12 – Rev July 2014
4. Where are the interstitial cells located? What is the function of these cells? (2
marks)
5. Identify the parts of a mature sperm and state the function of each part. (8 marks)
6. Explain how the hypothalamus and anterior pituitary gland function together to
regulate sperm and testosterone production. Please explain the entire feedback
loop using your own words/phrasing. (7 marks)
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BCLN BIOLOGY 12 – Rev July 2014
7. Label the following diagram of the female reproductive system. Provide a brief
description of each structure's function below the diagram. Please be neat. (10
marks)
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BCLN BIOLOGY 12 – Rev July 2014
8. Give two ways that the oviduct aids the passage of the egg towards the uterus.
(2 marks)
9. List five different effects of estrogen on the female body. (5 marks)
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BCLN BIOLOGY 12 – Rev July 2014
10. Complete the following table in relation to the female reproductive cycle. (13
marks)
Hormone
Full Name
Source
Effects
GnRH
FSH
LH
Estrogen
Estrogen
Progesterone
Progesterone
11. The Ovarian Cycle:
a. Identify the name given to Days 1-13 of the ovarian cycle and describe the
changes in hormones and ovarian structures that occurs during this time.
(3 marks)
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BCLN BIOLOGY 12 – Rev July 2014
b. Identify the name of the event that occurs on Day 14 of the ovarian cycle
and specifically identify how hormone levels are responsible for
influencing its occurrence. (2 marks)
c. Identify the name given to Days 15-28 of the ovarian cycle and describe
the changes in hormones and ovarian structures that occurs during this
time. (3 marks)
12. The Uterine Cycle:
a. Identify the name given to Days 1-5 of the uterine cycle and describe the
changes in hormones and uterine structure that occurs during this time. (3
marks)
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BCLN BIOLOGY 12 – Rev July 2014
b. Identify the name given to Days 6-13 of the uterine cycle and describe the
changes in hormones and uterine structure that occurs during this time. (3
marks)
c. Identify the name given to Days 15-28 of the uterine cycle and describe
the changes in hormones and uterine structure that occurs during this
time. (3 marks)
13. Pregnancy and birth:
a. Define implantation. (1 mark)
b. What hormone is released from the membrane surrounding the embryo to
prevent corpus luteum from degenerating? (1 mark)
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BCLN BIOLOGY 12 – Rev July 2014
c. Why is it important to prevent the corpus luteum from degenerating
following implantation? (1 mark)
d. What tissues does the placenta originate from? What are the hormonal
and physical functions of the placenta? (3 marks)
e. Why do the levels of estrogen and progesterone remain high during
pregnancy and why is this important? (2 marks)
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BCLN BIOLOGY 12 – Rev July 2014
f. What are the functions of the hormone oxytocin and where does in
originate? Describe positive feedback as it relates to this hormone. (4
marks)
~ END OF BIOLOGY 12 UNIT 15 LEARNING GUIDE ~
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BCLN BIOLOGY 12 – Rev July 2014
UNIT 15 ANSWER KEY
U15 PRACTICE: REPRODUCTIVE SYSTEMS
1. Label the following diagram of the male reproductive system. Provide a brief description of each
structure's function below the diagram. Please be neat. (20 marks)
Testes = produce sperm and testosterone
Scrotum = hold testes away from body at a slightly lower temperature than body
temperature as this is ideal for healthy sperm production
Epididymis = stores sperm as they mature
Seminal vesicle = contributes to seminal fluid
Cowper's gland/Bulbourethral gland = contributes to seminal fluid
Prostate gland = contributes to seminal fluid
Urethra = conduct sperm (and urine) out of the body)
Vas deferens = carries sperm form testes to urethra
Penis = organ of copulation
Urinary bladder = stores urine
Erectile tissue/Corpora Cavenosa = fills with blood to create an erection
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BCLN BIOLOGY 12 – Rev July 2014
2. Why does sterility result if the testes do not descend into the scrotum? (2 marks)
If testes remain within body they are held at a temperature that is too high to
produce healthy sperm.
3. What is spermatogenesis and where does it occur? (2 marks)
= production/development of sperm and it occurs in the testes
4. Where are the interstitial cells located? What is the function of these cells? (2 marks)
= also known as Leydig cells, they are adjacent to the seminiferous tubules within
the testes where they produce testosterone
5. Identify the parts of a mature sperm and state the function of each part. (8 marks)
Head = contains DNA and the acrosomal cap that contains enzymes helps sperm to
penetrate egg
Mid-piece = contains mitochondria to provide ATP to power flagella movement
Tail/Flagella = propels sperm
6. Explain how the hypothalamus and anterior pituitary gland function together to regulate sperm
and testosterone production. Please explain the entire feedback loop using your own
words/phrasing. (7 marks)
The hypothalamus release Gonadotropin Releasing Hormone (GnRH) which then
causes the anterior pituitary to release Follicle Stimulating Hormone (FSH) and
Luteinizing Hormone (LH). FSH causes Sertoli cells of the testes to help sperm
development while LH causes Interstitial (Leydig) cells of testes to release
testosterone. Testosterone further stimulates Sertoli cell of testes to help sperm
development. However, as testosterone levels rise they have a negative feedback
effect on the hypothalamus and anterior pituitary such that the release of GnRH,
LH and FSH are blocked.
With these hormones blocked, less testosterone is
released and testosterone levels begin to fall until they reach such levels that the
negative feedback effect is lost and the cycle begins again, thus maintaining
homeostasis within the male reproductive system.
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BCLN BIOLOGY 12 – Rev July 2014
7. Label the following diagram of the female reproductive system. Provide a brief description of
each structure's function below the diagram. Please be neat. (10 marks)
oviduct
fimbriae
uterus
cervix
vagina
Fimbriae = sweep egg into oviduct as it is released from the ovary
Oviduct = typical site of fertilization, conducts egg to uterus
Uterus = site where fetus develops
Cervix = entry way between vagina and uterus
Vagina = receives penis during sexual intercourse, canal where menstrual fluid exit
body, canal where fetus exits body
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BCLN BIOLOGY 12 – Rev July 2014
8. Give two ways that the oviduct aids the passage of the egg towards the uterus. (2 marks)
- Mucous layer lining the oviduct secretes substances that aid in egg movement
-
Peristalsis (rhythmic contractions) move egg along the oviduct toward the uterus
9. List five different effects of estrogen on the female body. (5 marks)
-
Stimulates breast development during puberty
-
Stimulates maturation of uterus during puberty
-
Prepares uterus to nourish a developing fetus
-
Helps maintain bone density
-
Development of secondary sex characteristics of females including breasts,
wider hips, greater fat deposition, development of arm pit and pubic hair
10. Complete the following table in relation to the female reproductive cycle. (13 marks)
Hormone
Full Name
Source
Gonadotropin
GnRH
Releasing
hypothalamus
Hormone
Follicle
FSH
Stimulating
Pituitary gland
Hormone
LH
Luteinizing
Hormone
Pituitary gland
Effects
Causes pituitary gland to release LH and
FSH
Causes ovaries to produce a mature
follicle (egg)
Causes ovary to release egg
Lower levels stimulate endometrium
Estrogen
Estrogen
ovary
development in uterus, high levels prevent
GnRH release
Progesterone
Progesterone
ovary
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Stimulates endometrium development in
the uterus, high levels inhibit LH release
BCLN BIOLOGY 12 – Rev July 2014
11. The Ovarian Cycle:
a. Identify the name given to Days 1-13 of the ovarian cycle and describe the changes in
hormones and ovarian structures that occurs during this time. (3 marks)
= Follicular Phase
= hypothalamus releases GnRH causing anterior pituitary to release FSH and
LH which causes egg maturation
b. Identify the name of the event that occurs on Day 14 of the ovarian cycle and specifically
identify how hormone levels are responsible for influencing its occurrence. (2 marks)
= Ovulation = egg released
= high levels of LH trigger this event
c. Identify the name given to Days 15-28 of the ovarian cycle and describe the changes in
hormones and ovarian structures that occurs during this time. (3 marks)
= Luteal Phase
= corpus luteum secretes estrogen and progesterone which influence the
uterine cycles
= if pregnancy does not occur the corpus luteum disintegrates, estrogen and
progesterone levels drop and menstruation (uterine cycle) occurs
12. The Uterine Cycle:
a. Identify the name given to Days 1-5 of the uterine cycle and describe the changes in
hormones and uterine structure that occurs during this time. (3 marks)
= Menstruation
= low levels of estrogen and progesterone lead to endometrium (lining of
uterus) breaking down and being expelled from body
b. Identify the name given to Days 6-13 of the uterine cycle and describe the changes in
hormones and uterine structure that occurs during this time. (3 marks)
= Proliferative Phase
= increased production of estrogen by the maturing egg in the ovary lease to
rebuilding of the endometrium in preparation for the potential of a
fertilized egg implanting
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BCLN BIOLOGY 12 – Rev July 2014
c. Identify the name given to Days 15-28 of the uterine cycle and describe the changes in
hormones and uterine structure that occurs during this time. (3 marks)
= Secretory Phase
= increased levels of progesterone released by the corpus luteum in the
ovary causes the endometrium to double in thickness, become highly
vascularized and to produce mucus such that it is ready to receive a
fertilized egg (embryo)
13. Pregnancy and birth:
a. Define implantation. (1 mark)
= when a fertilized egg (embryo stage) embeds itself in the endometrium of
the uterus several days after the fertilization event
b. What hormone is released from the membrane surrounding the embryo to prevent corpus
luteum from degenerating? (1 mark)
= the Human Chorionic Gonadotropin hormone (HCG) which is what pregnancy
tests are designed to detect
c. Why is it important to prevent the corpus luteum from degenerating following
implantation? (1 mark)
= if the corpus luteum disintegrates too early the estrogen and progesterone
levels will drop causing the endometrial lining (and the implanted embryo) to
be shed…effectively a miscarriage
d.
What tissues does the placenta originate from? What are the hormonal and physical
functions of the placenta? (3 marks)
= maternal and fetal tissues
= produces HCG hormone to maintain the corpus luteum
= movement of nutrients from mother's blood to fetal blood, movement of
waste from fetal blood to mother's blood
e. Why do the levels of estrogen and progesterone remain high during pregnancy and why
is this important? (2 marks)
= remain high due to maintenance of corpus luteum by HCG hormone
(produced by placenta)
= necessary to prevent shedding of the endometrial lining and developing
fetus
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BCLN BIOLOGY 12 – Rev July 2014
f.
What are the functions of the hormone oxytocin and where does in originate? Describe
positive feedback as it relates to this hormone. (4 marks)
= oxytocin causes the uterus to contract which then initiates a positive
feedback loop causing further release of oxytocin and further contractions
and so on until the baby is delivered
= oxytocin also is released in response to a baby suckling and causes the
mammary glands to release milk
= oxytocin is released from the posterior pituitary
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