science 10 module

1. Science
Quarter 3 - Module 2
Feedback Mechanisms in the
Female Reproductive System
Department of Education ● Republic of the Philippines
10

2. Science- Grade 10
Alternative Delivery Mode
Quarter 3 – Module 2: Feedback Mechanisms in the Female Reproductive System
First Edition, 2020
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Published by the Department of Education – Division of Bukidnon
Schools Division Superintendent: Dr. Randolph B. Tortola, CESO V
Development Team of the Module
Author/s : Crystal Jade S. Mongas
Content Editor : Loniel D. Barro, PhD
Language Editor : Maria Luisa M. Casiño
Reviewers : Ellen A. Azuelo, PhD, Rejynne Mary L. Ruiz, PhD
Illustrator and Layout Artist : Crystal Jade S. Mongas
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Schools Division Superintendent
: Shambaeh A. Abantas-Usman, PhD
Assistant Schools Division Superintendent
: Mala Epra B. Magnaong, Chief ES, CLMD
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3. 1
Lesson
1
The Menstrual Cycle
What’s New
WHAT’S THE WORD?
Direction: Observe the four pictures and solve the puzzle by working out what the word is.
Every box corresponds to a certain letter. Write your answer in a separate
sheet of paper.
Figure 1.1 What’s the word model
Source: www.google.com Images Labeled for Reuse
Were you able to figure out the
mystery word? Excellent! This process only
occurs among females. It is a normal vaginal
bleeding that occurs as part of a female’s
monthly cycle which is known as
menstruation.

4. 2
What Is It
We have previously discussed that an ovary normally releases only one egg every 28
days. What controls the timing are the hormones. Hormones control many of the changes in
the reproductive system. They also coordinate the development of the ovum and the uterus.
Remember that hormones are chemicals that can affect certain body organs. This cycle
among females occurs every month starting when a female is 10 to 13 years old and it
continues for about 40 years. If an ovum is not fertilized in the fallopian tube, the corpus
luteum degenerates, the progesterone production stops, and the inside membrane of the
uterus breaks down. The breakdown and discharge of the soft uterine tissues and the
fertilized egg is called menstruation. This is the monthly changes or periods that take place
in the female reproductive system.
The Menstrual Cycle
The female sex hormones control the secondary sex characteristics as well as the
ovarian and uterine cycle. Like males, females also secrete follicle stimulating hormone
(FSH) and luteinizing hormone (LH) as directed by the pituitary gland during puberty. This
signals the start of puberty which includes the development of the secondary sex
characteristics in females and the onset of menstruation. A female experiences body
changes even before the first menstruation which is also known as menarche. The female
secondary sex characteristics include the development of the breast; growth of underarm
and pubic hair; rounded body shapes brought about by a widespread layer of fat in areas like
the abdomen, hips and thighs; widening of the hips in preparation for childbirth; and the
development of higher pitched voice. At puberty, the master gland which is the pituitary
gland starts a series of hormonal changes that make a woman capable of pregnancy. These
hormonal changes and the effects they produce is called the menstrual cycle. While the
length of this cycle varies, the typical cycle is about 28 days. During this process, changes in
both the ovary and the uterus take place.
The Ovarian Cycle
At the start of the cycle, the pituitary gland secretes increased amount of FSH and
this allows an ovarian follicle to mature. The female sex hormone called estrogen, is also
secreted as the follicle cells develop. When the follicle cells multiply, the cells signal an
increased level of estrogen in the blood, and the pituitary gland secretes another hormone,
the luteinizing hormone (LH).
LH and FSH bring about the maturation of the follicle which results to ovulation -- the
releasing of the mature egg. Ovulation usually occurs on the 14th
day of the cycle. During
ovulation, the egg is ready for fertilization within 24 hours from its release. Still under the
influence of LH, the cells of the ruptured follicle develop into a yellow body called the corpus
luteum. The yellow body then produces more estrogen and another female sex hormone
called the progesterone. Both hormones prepare the uterine wall for the possible
implantation of a fertilized egg. The rise in the level of estrogen and progesterone exerts a
feedback control over the pituitary gland to inhibit the secretion of LH and FSH. The corpus
luteum is deprived of the hormones that maintain it with the drop in the amount of these two
hormones, hence the corpus luteum begins to degenerate. Thus, the gland’s influence on
the progesterone level will affect the endometrial wall in a domino effect.

5. 3
The Uterine Cycle
A series of changes also happens in the uterus as a consequence of the hormones
while events are taking place in the female’s ovary. With the low levels of progesterone, the
surface of the endometrium or wall begins to disintegrate and the blood vessels rupture.
Blood and some accompanying endometrial tissues flow out of the vagina in a process
called menstruation. This menstrual phase lasts for about five days.
After the menstrual period, the endometrium starts to build up due to the increasing
amount of estrogen by the developing follicles in the ovary. This is the proliferative phase of
the uterine cycle which lasts for 6 to 14 days. The formation of the corpus luteum and the
secretion of progesterone trigger the endometrium to double in thickness and prepare itself
for a developing embryo. The uterine glands also become mature and they produce a thick
secretion. Hence, the secretory phase of the uterine cycle begins on the 15th
day until before
the onset of the next menstrual phase. However, this cycle may be interrupted by stress,
health concerns and pregnancy. But if pregnancy does not occur, the cycle begins anew.
Figure 1.3 The ovarian and uterine cycle
Source: www.google.com Labeled for Reuse
Figure 1.2 The ovary
Source: www.google.com Labeled for Reuse

6. 4
What’s More
ACTIVITY 1: CAN YOU DESCRIBE ME?
In this activity, you will describe how menstruation occurs in the female reproductive system.
Direction: Study the diagram below to describe how menstruation occurs and answer the
guide questions that follow.
Guide Questions
1. Record your observations on the table below.
Phases
Hormones Involved
2. How does the menstrual cycle occur in females?
_____________________________________________________________
_____________________________________________________________
Were you able to record your
observations? Good job! Remember,
hormones coordinate the development of
the ovum and the uterus.
Figure 1.4 The phases/cycles
Source: www.google.com Labeled for Reuse

7. 5
ACTVITY 2: FROM THE PITUITARY WITH HUGS
Objective
Explain how the hormones are involved in the reproductive systems
Procedure
1. Analyze the picture and take note of your observations.
2. Organize your ideas and explain the roles of hormones in the male and female
reproductive systems.
3. From the following choices, select the appropriate word that would make the
sentences correct. Choose only the CAPITAL LETTER.
A. Hormones D. Ovaries
B. Reproductive System E. Follicles
C. Testes F. Uterus
(1) _____________ play an important role in both the male and female (2)
_____________. The (3) _____________ gland controls the functions of both the (4)
_____________ and (4) _____________. These hormones keep the (5) _____________
working properly.
The production of sperm cells and the release of semen can be regulated by (6)
_____________. The female reproductive system, just like the male reproductive system, is
also regulated by hormones. The (7) _____________ produce hormones that control the
growth and release of eggs from the (8) _____________. While other hormones prepare the
(9) _____________ so a baby can develop and other (10) _____________ still control the
stretching of the uterus during pregnancy.
Good job! You were able to
explain the roles of hormones in the
male and female reproductive systems.
Keep up the good work!
Figure 1.5 Human free body diagram
Source: www.google.com Labeled for Reuse

8. 6
What I Have Learned
Now, let us try to remember the concepts that you have just learned today. Ready,
set, go!
Direction: Answer the following question in complete sentences. (15 points)
What are the functions of the ovaries, follicles, follicle stimulating hormone,
corpus luteum, and progesterone?
What I Can Do
DIFFERENTIATED TASK
Direction: Choose only ONE TASK from the following activities:
A. Make a healthy advisory letter that will provide information about
menstruation and the female reproductive system.
B. Compose a jingle with lyrics or content talking about menstruation and the
female reproductive system.
C. Make a poster with a slogan that illustrates menstruation and the female
reproductive system.
D. Make a brochure about menstruation and the female reproductive system.
E. Make a poem about menstruation and the female reproductive system.
RUBRIC FOR SELF-CHECK
(To be used by the teacher in rating the output)
Accuracy of the Content 30 %
Organization and Coherence of Idea 20 %
Clarity of the Message 20 %
Creativity 20 %
Completeness 10 %
TOTAL 100 %
Direction: Choose the CAPITAL LETTER of the best answer. Write the chosen letter on a
separate sheet of paper.
1. Which days of the cycle does menstruation occur?
A. days 1-6 B. days 7-13 C. days 14-20 D. days 21-28
Assessment

9. 7
2. A biologist made a hypothesis that the pituitary and the ovary both influence the uterine
cycle in females. Which of the following observations would best support this hypothesis?
A. The removal of the pituitary is followed by death.
B. The removal of the ovary can greatly affect the menstrual cycle.
C. The removal of the ovary is followed by a non-functioning pituitary.
D. The uterine development takes place only when both pituitary and ovary are present.
3. A woman’s unsafe period is the day near or during _________.
A. fertilization B. menstruation C. ovulation D. sexual intercourse
4. In a typical 28-day menstrual cycle, on which day following the beginning of the menstrual
period is the level of the luteinizing hormone most likely to be the highest?
A. day 7 B. day 14 C. day 21 D. day 28
5. What happens during ovulation?
A. A sperm can fertilize an egg. C. An ovum is released from the ovary.
B. A zygote becomes an embryo. D. A follicle releases the hormone FSH.
6. Which of the following is responsible for a series of hormonal changes?
A. thyroid gland B. pituitary gland C. parathyroid gland D. thyme gland
7. When does ovulation usually occur?
A. 7th
day B. 14th
day C. 21st
day D. 28th
day
8. Why does the endometrium start to build up after the menstruation period?
A. Due to the increasing amount of estrogen
B. Due to the decreasing amount of estrogen
C. Due to the increasing amount of progesterone
D. Due to the decreasing amount of progesterone
9. When does the secretory phase of the uterine cycle begin?
A. 14th
day B. 15th
day C. 21st
day D. 22nd
day
10. Which of the following refers to the first menstruation?
A. menstrual cycle C. ovulation
B. menarche D. fertilization
11. In which of the following is there an increased amount of FSH?
A. menstrual cycle C. uterine cycle
B. ovarian cycle D. all of the choices
12. The cells of the ruptured follicle develop into a yellow body called the __________.
A. menarche C. corpus luteum
B. luteinizing hormone D. follicle stimulating hormone
13. How long does the proliferative phase of the uterine cycle last?
A. 5-10 days B. 6-14 days C. 7-14 days D. 8-21 days
14. Which development after menstruation causes the endometrium to start building up?
A. developing follicles C. developing uterus
B. developing ovary D. developing uterine lining
15. Which of the following is the breakdown and discharge of the soft uterine tissues and the
fertilized egg?
A. pregnancy B. menstrual cycle C. menarche D. menstruation

10. 8
Lesson
2
Hormone Feedback and
Menstruation
What’s New
Menarche is the most obvious signal of the onset of puberty in females. This is
the first menstrual discharge of
blood from the vagina.
Menarche also signals the
beginning of cyclic changes in
the ovary.
Oocytes that were
unripe or untouched are now
brought up to become active.
Thus, every month, an ovarian
cycle takes place. Figure 2.1
shows the changes in the lining
of the uterus as the month
progresses.
Before moving on, let us first
try an activity. In this activity, you are expected to compare the changes that occur during the
menstrual cycle. Try to figure out what occurs in its every stage.
Direction: Complete the table below by comparing the changes that occur during the
menstrual cycle.
Part Event Number
of Days
Hormone
Produced
Blood Flow Menstruation
occurs.
Follicular The follicles
are formed in
the ovary.
Ovulation The oocytes
burst from the
ovary.
Luteal The corpus
luteum is
formed.
Figure 2.1 Changes in the uterine lining
Source: www.google.com Labeled for Reuse

11. 9
What Is It
The human ovaries can usually produce only one egg during a 28-day cycle of
activity. The mass of ovarian
cells produces an ovum or an
egg and it also forms a follicle.
The cycle is controlled by FSH
or the Follicle-Stimulating
Hormone. This hormone is
produced in the anterior lobe
of the pituitary gland. The
follicle becomes filled with a
fluid containing the hormone
estrogen when the egg
reaches maturity. Most
importantly, the rising level of
FSH stimulates follicle
maturation and estrogen production.
Figure 2.2 shows the cross section of a human ovary with different stages of
development. As the cycle continues and after the ovum has been discharged, the follicle
turns yellow and it forms the corpus luteum. The yellow body formation is controlled by
another hormone of the pituitary gland called the LH or luteinizing hormone. The corpus
luteum then produces another hormone known as progesterone. Progesterone brings about
effects in the secondary characteristics primarily on the breasts. During pregnancy,
progesterone causes breast enlargement. Moreover, this hormone maintains the growth of
the mucus lining of the uterus.
To summarize, the important female hormones are as follows:
Female
Hormone
Location Function
Estrogen Follicles/Ovary Responsible for secondary
female characteristics;
thickens endometrium;
inhibits growth of facial hair
Progesterone Corpus
Luteum/Ovary
Stimulates endometrium;
inhibits uterine contractions
and ovulation
LH Pituitary Gland Develops and maintains the
corpus luteum; stimulates
ovulation
FSH Pituitary Gland Stimulates the formation of
follicles in the ovaries
Figure 2.2 A cross section of the ovary

12. 10
Have you experienced menstrual cramps? Probably yes,
you have. In reality, some females experience menstrual cramps every
month. Did you know that menstrual cramps are the results of the strong
contractions of the uterine wall that occur before and during menstruation?
What do you think is its cause?
Cramps can be caused by the excessive secretion of
prostaglandins. Shedding of the endometrium of the uterus results in the
inflammation of the endometrial layer. As a consequence of this inflammation,
prostaglandins are produced.
In a nutshell, the following summarizes the important events during the menstrual
cycle:
1. The pituitary gland begins the cycle.
2. The pituitary releases hormones that cause the egg in the ovary to mature.
The luteinizing hormone (LH) initiates the maturation of the follicles, converts
ruptured follicle into the corpus luteum and cause the secretion of
progesterone. The other hormone, follicle stimulating hormone (FSH)
assists in the maturation of the follicles and cause the secretion of estrogen
from the follicles.
3. Meanwhile, the ovary itself releases a hormone called estrogen. Estrogen is a
hormone that causes changes in the female reproductive system. This
hormone also causes the uterus to increase in thickness. The uterus becomes
thicker so that the fertilized egg can attach to it.
4. The ovary releases an egg on day 14. Now, assume that no sperm was present.
5. The egg moves through the oviduct and enters the uterus.
6. At the same time, the uterus continues to thicken.
7. The egg has not been fertilized, therefore, it will not attach to the uterus.
8. The thick uterus is no longer necessary, so it begins to break apart. The cells of
the thickened uterus break off and leave the vagina. The unfertilized egg is also
lost. Some blood is lost, too. This loss of cells from the uterus lining, blood and
egg is called menstruation.
9. After menstruation, the cycle starts again.
What is a feedback mechanism?
Figure 2.3 Negative feedback mechanisms in the menstrual cycle

13. 11
A feedback mechanism is the process through which the level of a certain
substance influences the level of another substance. A negative feedback affects the
production of hormones in the menstrual cycle. Moreover, high levels of one
hormone may inhibit the production of another hormone. Figure 2.3 presents the
negative feedback mechanisms in the menstrual cycle. Based on the figure, follicle
stimulating hormone or FSH stimulates the ovaries to release estrogen. High levels
of estrogen then prevent more production of FSH. Estrogen then stimulates the
release of luteinizing hormone or LH from the pituitary gland, which in turn, controls
the production of progesterone. Moreover, high levels of progesterone can then
inhibit the further release of LH.
What’s More
ACTIVITY 1: CAN YOU JUSTIFY ME?
Objective
Determine the hormones involved in regulating the processes in the female
reproductive system
Procedure
Check “Yes” if the hormone is involved in regulating the given process, otherwise
check “No”. If your answer is “No”, please state the reason behind it. Write your
answers in the table.
Hormone Yes No Reason
1. Adrenocorticotropic
2. Estrogen
3. Antidiuretic Hormone
4. Progesterone
5. Parathyroid Hormone
6. Luteinizing Hormone
7. Epinephrine
8. Follicle Stimulating Hormone
9. Testosterone
10. Melatonin
Congratulations for being able
to determine the hormones
involved in regulating the
processes in the female
reproductive system!

14. 12
ACTIVITY 2: THERE’S A FEEDBACK!
A.
Objective
Describe the feedback mechanisms involved during a menstrual cycle
Materials
2 calendar charts
diagrams of the male and female reproductive systems
scissors
tape or glue
Procedure
Part A – FOR NO FERTILIZATION
1. Get a calendar. It must be marked with the day-to-day changes in the menstrual
cycle.
2. Note that certain events are marked on certain days.
3. Make a copy of the diagrams of the menstrual cycle like those found in the next
page. Some of the diagrams will show the events in the ovary, and some will
show the events in the uterus. They are not in the proper order, though. Cut out
each square.
4. Place the diagram in the space to the right of the corresponding description.
5. Tape or glue your diagrams in the right places/dates where they occur.
6. Make sure that they are correctly placed.
Part B – WITH FERTILIZATION OF THE EGG
1. Get another calendar marked by the day-to-day changes in the menstrual cycle.
2. Again you will be given a set of diagrams to place on the calendar. The
diagrams will not be in proper order. Also, you may not need all the diagrams
that show the uterus.
Observations:

15. 13
B. Study the given pictures to describe the feedback mechanisms involved during the
menstrual cycle and answer briefly the guide questions below.
Source: www.google.com Images Labeled for Reuse
Guide Questions
1. How long does a menstrual cycle usually last if fertilization has not taken place?
2. Describe what happens to the egg during the first 14 days of the cycle in Part B.
3. Describe what happens to the egg and the uterus during the last 14 days of the
cycle in Part A.
4. What takes place after fertilization?
Direction: Answer the following question in complete sentences. (15 points)
Why is the menstrual cycle an important adaptation for reproduction in humans?
What I Can Do
DIFFERENTIATED TASK
Direction: Choose only ONE TASK from the following choices.
A. Make a poem about the role of hormones in the female reproductive system.
B. Compose a jingle with lyrics or content talking about the feedback mechanism
in the female reproductive system.
C. Make a poster with a slogan that illustrates the feedback mechanism involved
in the female reproductive system.
D. Produce a newscast about what happens when the body produces more follicle
stimulating hormone and luteinizing hormone.
E. Make a brochure about the feedback mechanism in the female reproductive
system.
What I Have Learned
A B

16. 14
RUBRIC FOR SELF-CHECK
(To be used by the teacher in rating the output)
Accuracy of the Content 30 %
Organization and Coherence of Idea 20 %
Clarity of the Message 20 %
Creativity 20 %
Completeness 10 %
TOTAL 100 %
Assessment
Direction: Choose the CAPITAL LETTER of the best answer. Write the chosen letter on a
separate sheet of paper.
1. Which of the following hormones is responsible for the secondary female characteristics?
A. estrogen B. progesterone C. LH D. FSH
2. Which hormone stimulates the endometrium?
A. estrogen B. progesterone C. LH D. FSH
3. Which of the following inhibits uterine contractions and ovulation?
A. estrogen B. progesterone C. LH D. FSH
4. Which hormone develops and maintains the corpus luteum?
A. estrogen B. progesterone C. LH D. FSH
5. The _________ stimulates the formation of follicles in the ovaries.
A. estrogen B. progesterone C. LH D. FSH
6. It is the process through which the level of a certain substance influences the level of
another substance.
A. FSH B. LH C. menstruation D. feedback
7. An increase in FSH may also indicate a reduction in the production of good quality eggs
and embryos for _________.
A. fertilization B. menstruation C. ovulation D. all of the choices
8. It is an abnormally high levels of LH during non-ovulatory times in the menstrual cycle.
A. menarche B. menopause C. LH D. FSH
9. Which phase signals the beginning of cyclic changes in the ovary?
A. menarche B. menopause C. LH D. FSH
10. The mass of ovarian cells produces a/an _______.
A. sperm B. ovum C. LH D. FSH
11. What hormone does the corpus luteum produce?
A. estrogen B. progesterone C. LH D. FSH
12. What hormone brings about significant effects primarily on the breasts?
A. estrogen B. progesterone C. LH D. FSH
13. During pregnancy, what hormone causes breast enlargement?
A. estrogen B. progesterone C. LH D. FSH
14. What results during strong contractions of the uterine wall?
A. menarche B. menstruation C. menstrual cramps D. AOTC
15. What happens to the cycle after menstruation?
A. The cycle ceases. C. The cycle reverses.
B. The cycle starts again. D. The cycle ends.

17. 15
Lesson
3
Hormone Feedback and
Pregnancy
What’s New
Now that you have already known about the parts and functions of the human
reproductive system, let us now trace what happens to the ovulated egg to its orderly
sequence of events from the time an egg is ovulated. In this activity, you should be able to
arrange the sequence from the beginning to the end of fertilization and implantation in the
uterus.
Direction: Complete the table below by sequencing the events from the time an egg is
ovulated. Arrange orderly by numbering the items from 1 to 7. Write your answer
inside the table.
Event Sequence
Fertilized egg attaches to the uterus
Fertilized egg moves out of the oviduct
Egg is fertilized in the oviduct
Vagina receives the sperm
Egg moves into the oviduct
Egg is released from the ovary
Egg is in the ovary
Well done! You were able to perform the activity! You many proceed to the next. Have fun!

18. 16
What Is It
A zygote or a fertilized egg is formed when a sperm successfully penetrates the
nuclei fuse. A fertilization membrane develops to prevent other sperms to further penetrate
the egg. This process wherein the sperms’ nucleus
and the ovum’s unite is called fertilization. It
usually takes place while the egg is traveling along
the oviduct or fallopian tube. It will take about 7 to
10 days for an egg, fertilized or not, to reach the
uterus.
Upon successful implantation of a
developing embryo in the endometrium, the
developing embryo and the uterine lining jointly
form a special organ called the placenta. This will
provide nourishment for the embryo. It also
secretes the hormone called human chorionic
gonadotropin (HCG), which is related to LH since
they act on the same receptor. Remember that the
LH maintains the corpus luteum. With the corpus
luteum intact, progesterone production is maintained and the uterine wall will not
menstruate. HCG actually passes in the urine. It is the same hormone detected in pregnancy
tests. If the embryo is abnormal or if it dies, HCG will drop and the endometrium will
disintegrate causing a woman to have a miscarriage.
As your guide, refer below for the summary of the stages of reproduction:
1. Egg cells are formed in each ovary.
2. Each month, one ovary releases an egg. Normally, only one egg is
released about every 28 days. The ovaries usually take turns in releasing
the eggs.
3. Once released from the ovary, the egg moves into a tube called oviduct.
Oviducts are tube-like organs that connect the ovaries to the uterus. The
uterus is a muscular organ in which the fertilized egg develops.
4. Sperm cells are released into the vagina during mating. The vagina is a
muscular tube that leads from the outside of the female’s body to the
uterus. Sperm cells swim from the vagina into the uterus and into the
oviducts. If an egg is present, fertilization takes place. Once fertilized, the
egg moves down the oviduct into the uterus.
5. The fertilized egg then attaches itself into the wall of the uterus which is
Figure 3.1 The zygote
Source: www.google.com Image Labeled for Reuse
Figure 3.2 Pregnancy test
Source: www.google.com Image Labeled for Reuse

19. 17
called implantation. Once attached, it will remain there for nine months as
it develops into a baby.
What is ectopic
pregnancy? Ectopic pregnancy
results if implantation occurs
anywhere other than the uterine
cavity. The most common site of
ectopic pregnancy is in the
fallopian tube. Implantation in
the fallopian tube can be fatal
and can cause the tube to
rupture. In some cases,
implantation can occur in the
mesenteries of the abdominal
cavity and the fetus can develop
normally, but must be delivered
by caesarian section.
As a summary, outlined below are the different processes involved during pregnancy.
Ovulation
This refers to the release of a mature egg from the ovary. It usually takes
place on the 14th
day from the first day of menstruation if the cycle is a 28-day cycle.
Fertilization
When a sperm encounters an egg cell in the fallopian tube, it releases
digestive enzymes. Those enzymes clear the path for the sperm nucleus to fuse with
the nucleus of the ovum or egg cell. A zygote is now formed.
Implantation
This occurs before the end of the first week. By this process, the zygote
attaches to the uterine lining, and some of its cells send out projections that has been
part of the maternal tissue. The inner cell mass becomes the embryonic disc. This disc
Figure 3.4 A cross section of the ovary
Source: www.google.com Image Labeled for Reuse
Figure 3.3 A human embryo
Source: www.google.com Image Labeled for Reuse

20. 18
will give rise to the embryo proper during the week following implantation.
Birth or Parturition
“Happy birthday!” is a very common greeting to mark the anniversary of a person’s
birth.
Birth takes place about 39 weeks after fertilization. The birth process begins when
the uterus starts to contract. For the next two to eighteen hours, the contraction becomes
stronger and more frequent. The cervical canal dilates fully and the amniotic sac ruptures.
Birth typically occurs less than an hour after full dilation. Immediately afterward,
uterine contraction forces fluid, blood and the placenta out of the body. The umbilical cord
is now cut, and the newborn embarks on its nurtured existence in the outside world.
What’s More
ACTIVITY: A-MAZE-ING EGG RACE!
Objective Trace the processes involved during the release of an egg and fertilization
Procedure
Shade the arrow that correctly traces the processes involved during the release of an
egg. Your answers will guide you to the end of the maze.
What I Have Learned
Direction: Answer the question below in complete sentences. (15 points)
Why does menstruation stop when a woman becomes pregnant?

21. 19
What I Can Do
DIFFERENTIATED TASK
Directions: Choose only ONE TASK from the following:
A. Make a poem about the benefits of family planning and post it on your
Facebook account. You may include pictures of your family to
reinforce your point.
B. Select a tweet regarding Responsible Parenthood and Reproductive
Health Act of 2012 and share your thoughts about it. Post it on your
Facebook timeline.
C. Look for a short video about AIDS and help spread awareness and
prevention of AIDS through your social network. You may share it on
your Facebook, Twitter or Instagram accounts.
RUBRIC FOR SELF-CHECK
(To be used by the teacher in rating the output)
Accuracy of the Content 30 %
Organization and Coherence of Idea 20 %
Clarity of the Message 20 %
Creativity 20 %
Completeness 10 %
TOTAL 100 %
Assessment
Direction: Choose the CAPITAL LETTER of the best answer. Write the chosen letter on a
separate sheet of paper.
1. Which hormone prevents menstruation among pregnant women?
A. HCG B. LH C. oxytocin D. prolactin
2. HCG which is secreted by the chronic membrane is similar in structure and function to
______.
A. FSH B. LH C. estrogen D. progesterone
3. How many hours will the egg cell be viable for fertilization?
A. 12 hours B. 24 hours C. 48 hours D. 72 hours
4. The egg will most likely be fertilized while it is travelling in the ______.
A. cervix B. fallopian tube C. uterus D. vagina
5. What is formed when a sperm successfully penetrates the nuclei fuse?
A. egg B. sperm C. ovum D. zygote
6. Upon successful implantation of a developing embryo in the endometrium, the developing
embryo and the uterine lining jointly forms a special organ called the ______.
A. cervix B. fallopian tube C. placenta D. uterus
7. Where are egg cells found?
A. ovary B. uterus C. placenta D. vagina
8. What results if implantation occurs anywhere other than the uterine wall?

22. 20
A. menarche B. menopause C. ectopic pregnancy D. miscarriage
9. What occurs before the end of the first week by which the zygote attaches to the uterine
lining?
A. menstruation B. fertilization C. implantation D. ovulation
10. This secreted hormone provides nourishment to the embryo.
A. LH B. FSH C. HCG D. all of the choices
11. Sperm cells are released into the ________ during mating.
A. ovaries B. uterus C. fallopian tube D. vagina
12. What does the ovary release every month?
A. egg B. sperm C. LH D. FSH
13. What will drop if the embryo is abnormal or if it dies?
A. HCG B. LH C. FSH D. all of the choices
14. Which of the following results to the disintegration of endometrium?
A. menarche B. menopause C. menstruation D. miscarriage
15. Which of the following is the most common site of ectopic pregnancy?
A. ovaries B. fallopian tube C. uterus D. vagina
Assessment (Unit Test)
Direction: Choose the CAPITAL LETTER of the best answer. Write the chosen letter on a
separate sheet of paper.
1. Which days of the cycle does menstruation occur?
A. days 1-6 B. days 7-13 C. days 14-20 D. days 21-28
2. A biologist made a hypothesis that the pituitary and the ovary both influence the uterine
cycle in females, which of the following observation would best support this hypothesis?
A. The removal of pituitary is followed by death.
B. The removal of the ovary can greatly affect the menstrual cycle.
C. The removal of the ovary is followed by a non-functioning pituitary.
D. The uterine development takes place only when both pituitary and ovary are present.
3. A woman’s unsafe period is the day near or during _________.
A. fertilization B. menstruation C. ovulation D. sexual intercourse
4. In a typical 28-day menstrual cycle, on which day following the beginning of the menstrual
period is the level of luteinizing hormone most likely to be the highest?
A. day 7 B. day 14 C. day 21 D. day 28
5. What happens during ovulation?
A. A sperm can fertilize an egg. C. An ovum is released from the ovary.
B. A zygote becomes an embryo. D. A follicle releases the hormone FSH.
6. It is the process through which the level of a certain substance influences the level of
another substance?
A. FSH B. LH C. menstruation D. feedback
7. An increase in FSH may also indicate a reduction in the production of good quality eggs
and embryos for _________.
A. fertilization B. menstruation C. ovulation D. all of the choices
8. It is an abnormally high levels of LH during non-ovulatory times in the menstrual cycle.
A. menarche B. menopause C. LH D. FSH

23. 21
9. What signals the beginning of cyclic changes in the ovary?
A. menarche B. menopause C. LH D. FSH
10. Which of the following is produced by the mass of ovarian cells?
A. sperm B. ovum C. LH D. FSH
11. Where are the sperm cells released during mating?
A. ovaries B. uterus C. fallopian tube D. vagina
12. What does the ovary release every month?
A. egg B. sperm C. LH D. FSH
13. If the embryo is abnormal or if it dies, _______ will drop.
A. HCG B. LH C. FSH D. all of the choices
14. What results to the disintegration of the endometrium?
A. menarche B. menopause C. menstruation D. miscarriage
15. Which of the following is the most common site of ectopic pregnancy?
A. ovaries B. fallopian tube C. uterus D. vagina

24. 22
Assessment
1.
D
2.
B
3.
C
4.
B
5.
A
6.
B
7.
B
8.
A
9.
B
10.B
11.B
12.C
13.B
14.A
15.D
What
I
Know
1.
A
2.
B
3.
B
4.
C
5.
D
6.
D
7.
A
8.
B
9.
A
10.B
11.B
12.B
13.B
14.C
15.B
Assessment
1.
A
2.
B
3.
B
4.
C
5.
D
6.
D
7.
A
8.
B
9.
A
10.B
11.B
12.B
13.B
14.C
15.B
What
I
know
1.
A
2.
B
3.
B
4.
A
5.
D
6.
C
7.
A
8.
C
9.
C
10.C
11.D
12.A
13.A
14.D
15.B
Assessment
1.
A
2.
B
3.
B
4.
A
5.
D
6.
C
7.
A
8.
C
9.
C
10.C
11.D
12.A
13.A
14.D
15.B
What’s
More
Activity
1
1.
No-
synthesis
of
sex
steroids
2.
Yes
3.
No-
increases
water
absorption
4.
Yes
5.
No-
stimulates
Calcium
uptake
6.
Yes
7.
No-
increase
heart
rate,
blood
pressure
and
blood
sugar
8.
Yes
9.
No-
male
development
10.
No-
blocks
secretion
of
LH
and
FSH,
promotes
sleep
Activity
2
1.
28
days
2.
It
moves
out
of
the
uterus
3.
The
egg
is
fertilized
and
attaches
to
the
uterus
for
implantation
4.
Implantation
What's
More
Activity
What’s
More
Phases/Hormone
1.
Blood
Flow-
None
2.
Follicular-
Estrogen
3.
Ovulation-
None
4.
Luteal-
Estrogen
and
Progesterone
The
egg
travels
through
a
thin
tube
called
a
fallopian
tube
of
the
uterus.
If
the
egg
is
fertilized
by
a
sperm
cell,
it
attaches
to
the
wall
of
the
uterus,
where
overtime
develops
into
a
baby.
If
the
egg
is
not
fertilized,
the
uterus
lining
breaks
down
and
bleeds
causing
a
period.
1.
d
2.
e
3.
h
4.
g
5.
c
6.
b
7.
a
8.
f
What
I
Know
1.
D
2.
B
3.
C
4.
B
5.
A
6.
B
7.
B
8.
A
9.
B
10.B
11.B
12.C
13.B
14.A
15.D
ASSESSMENT
(UNIT
TEST)
1.
D
2.
B
3.
C
4.
B
5.
A
6.
D
7.
A
8.
B
9.
A
10.
B
11.
D
12.
A
13.
A
14.
D
15.
B
Answer Key
Lesson 1
Lesson 2
Lesson 3