SHS General Biology 2 Module

1. Biology
Quarter IV – Module 1
Reproduction and
Development
12
22
DEPARTMENT OF EDUCATION
DIVISION OF SAN JOSE DEL MONTE CITY
San Ignacio St., Poblacion, City of San Jose del Monte, Bulacan 3023

2. Biology – Grade 12
Alternative Delivery Mode
Quarter 4 - Module 1: Reproduction and Development
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3. Department of Education • Republic of the Philippines
12
Biology
Quarter IV – Module 1
Reproduction and
Development

4. ii
Introductory Message
This Self- Learning Module (SLM) is prepared so that you, our dear learners, can continue
your studies and learn while at home. Activities, questions, directions, exercises, and
discussions are carefully stated for you to understand each lesson.
Each SLM is composed of different parts. Each part shall guide you step-by-step as you
discover and understand the lesson prepared for you.
Pre-tests are provided to measure your prior knowledge on lessons in each SLM. This will tell
you if you need to proceed on completing this module or if you need to ask your facilitator or
your teacher's assistance for better understanding of the lesson. At the end of each module,
you need to answer the post-test to self - check your learning. Answer keys are provided for
each activity and test. We trust that you will be honest in using these.
Please use this module with care. Do not put unnecessary marks on any part of this SLM. Use
a separate sheet of paper in answering the exercises and tests. And read the instructions
carefully before performing each task.
If you have any questions in using this SLM or any difficulty in answering the tasks in this
module do not hesitate to consult your teacher or facilitator.
Thank you.

5. 1
What I Need to Know
CONTENT STANDARD
The learner will demonstrate understanding of the different types of reproduction and
development in plants and animals.
PERFORMANCE STANDARD
The learner will be able to compare and contrast the different types of reproduction and
development in plants and animals.
LEARNING COMPETENCY:
The learner understands how reproduction happens in plants and animals.
This module is about the plant and animal reproduction and development. You will
learn the similarities and differences of plant and animal reproduction.
After going through this module, you are expected to:
1. Know more about plant and animal reproduction and development,
2. learn the importance of reproduction and development,
3. compare and contrast plant and animal reproduction and development and
4. apply the lesson in research and real life situations.

6. 2
What I Know
Let us check your prior knowledge about plant and animal reproduction and development
by answering the set of questions below.
Directions. Choose the letter of the best answer. Write the chosen letter on a separate sheet
of paper.
1. It is the stage of development when egg cells and sperm cells are produced.
A. Reproduction C. Gametogenesis
B. Fertilization D. Organogenesis
2. It is the type of cell division by somatic or body cells which gives rise to two diploid
cells.
A. Binary Fission C. Mitosis
B. Fragmentation D. Meiosis
3. It is type of cell which has two sets of chromosomes.
A. Diploid C. Monoploid
B. Biploid D. Haploid
4. This process happens when a sperm cell unites with an egg cell.
A. Union C. Reproduction
B. Synapsis D. Fertilization
5. This is the middle layer of an animal gastrula.
A. Ectoderm C. Endoderm
B. Mesoderm D. Exoderm
6. It is type of asexual reproduction where an unfertilized egg cell develops into an adult.
A. Binary Fission C. Fragmentation
B. Parthenogenesis D. Pollination
7. This an embryonic root
A. Hypocotyl C. Epicotyl
B. Radicle D. Cotyledon
8. The process of transferring a pollen grain from the male flower’s anther to a female.
flower’s stigma.
A. Germination C. Fertilization
B. Gastrulation D. Pollination
9. It is the stage in embryonic development where organs begin to form.
A. Oganogenesis C. Gametogenesis
B. Gluconeogenesis D. Morphogenesis
10. It is called a fertilized egg.
A. Embryo C. Baby
B. Fetus D. Zygote
11. It is a part of the plant embryo which provides nutrients to the developing embryo.
A. Hypocotyl C. Epicotyl
B. Cotyledon D. Plumule
12. It is the process where stem cells become multiple types of cells.
A. Cell Differentiation C. Cell Transformation
B. Cell Division D. Cell Replication

7. 3
13. It is a type of reproduction which requires fertilization to occur.
A. Binary Fission C. Sexual Reproduction
B. Fragmentation D. Asexual Reproduction
14. A zygote which has undergone series of cell division. This is the stage before a fetus
is developed.
A. Cell C. Organ
B. Embryo D. Organism
15. This is known as the embryonic stem.
A. Cotyledon C. Hypocotyl
B. Epicotyl D. Radicle
What’s In
Fig 1. Philippine Population Census conducted by the Philippine Statistics Authority from
1990 to 2015 (Source: https://psa.gov.ph/sites/default/files/ird/popcen_graph_2.png)
1. What is your observation on the graph illustrated in Figure 1? What do you think is the
reason behind this?
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8. 4
Fig 2. Frog development. (Source:
https://www.khanacademy.org/science/biology/developmental-biology/signaling-and-
transcription-factors-in-development/a/frog-development-examples)
2. Illustrated in Figure 2 is the development of a frog. What can you observe in the figure?
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9. 5
What’s New
This section will help you understand the terms that will be introduced to you in
the lesson. Answer the crossword puzzle below on a separate sheet of paper.
5.
1. 6. 7.
2. 8
4.
3.

10. 6
Across Down
1. This occurs when a sperm cell
unites with an egg cell
1. This is the type of asexual
reproduction exhibited by
starfishes.
2. This occurs when zygotes turn
into an embryo after a series of
cell division, differentiation, and
migration.
6. The process where a stem cell
turns into different types of cells.
3. This is a zygote which undergone
development.
7. Process of organ formation in a
developing embryo.
4. Type of cell division exhibited by
somatic or body cells where the
result is diploid – a cell containing
two sets of chromosomes
8. Development process the zygote
undergoes once it starts dividing.
Overview
Plants and animals are products of reproduction. It starts from the union of a sperm
cell and an egg cell through fertilization, which in turn, forms a zygote. It develops into an
embryo through a series of mitotic cell divisions. As the organism grows, stem cells
undergo cell differentiation to form multiple types of cells. This module discusses how plants
and animals reproduce and develop.
A. Reproduction
Reproduction is the process where an offspring with resemblance to its parent is
made. It aims to repopulate an area and preserve the existence of a species. There are two
types of reproduction namely, sexual reproduction and asexual reproduction.
What is It

11. 7
Sexual reproduction requires fertilization to occur – the union of male and female
sex cells, a sperm cell and an egg cell, respectively. The egg cell contains maternal DNA
while the sperm cell contains paternal DNA. Each sex cell is haploid, therefore each
containing only one set of chromosomes. When the sperm fertilizes the egg, the two sets of
chromosomes combine, forming a diploid zygote. There are two types of fertilization namely
internal fertilization and external fertilization. External fertilization occurs when gametes
or sex cells unite outside the female body. This usually take place in an aquatic environment
where crustaceans (e.g., shrimp and crab), mollusks (e.g., clams and squids) certain types of
fish and sponges release their gametes to the environment via spawning.
On the other hand, internal fertilization occurs inside or near the body of the female.
The sperm is deposited into the female’s body through a penis via the cloaca. The cloaca is
a structure which serves as an opening for the urinary, gastrointestinal, and reproductive
systems in animals. The table below shows the three types of internal fertilization exhibited by
animals.
Type of Internal
Fertilization
Definition Examples
1. Oviparity Zygotes are deposited
outside the female’s body
Chickens, frogs, some types
of sharks, and platypuses
2. Ovoviviparity Zygotes are retained inside
the female’s body and are
nourished by the egg yolk
Anacondas, guppies, and
some lizards
3. Viviparity Zygotes are retained inside
the female’s body and are
nourished by the female’s
placenta
Placental mammals such as
apes and monkeys
Table 1. Three types of internal fertilization in animals
On the other hand, plants such as mosses, liverworts and hornworts use water to
facilitate fertilization. This is the reason why they thrive in moist environments. However, this
is no longer exhibited by higher plants such as flowering plants, instead it is facilitated by
pollination. Pollination occurs when a pollen is transferred from the anther of a male flower
to the stigma of a female flower. A pollen is a plant structure which transports the sperm and
protects it from the environment. Once it lands in a female flower’s stigma, it forms a pollen
tube, which serves as the passage of the sperm cells. Flowering plants undergo double
fertilization where two sperm cells are released from the pollen – one fertilizes the haploid
egg and the other one fertilizes the diploid polar nuclei. The fertilized egg becomes the zygote,

12. 8
which will develop into an embryo, and the fertilized polar nuclei becomes the endosperm,
which will provide nutrition for the developing embryo.
Fig. 1. Animal (photo on the left) and plant (photo on the right) fertilization.
Fragments or parts of animals and vegetative parts of plants are involved in this type
of reproduction. Stated below are types of plant and animal asexual reproduction and their
examples.
Asexual Reproduction
Type
Definition Examples
1. Budding An outgrowth develops in
the parent organism then
detaches itself
Hydra
2. Fragmentation A detached piece of an
animal develops into an
offspring via regeneration.
Starfish, annelid worms
3. Fission An animal divides into two
offspring
Coral polyps

13. 9
4. Parthenogenesis Unfertilized egg develops
into an adult
Honeybees, hammerhead
sharks, Komodo dragon
5. Vegetative
Propagation
The use of vegetative plant
parts such as stems and
leaves, to grow a new
organism
Kalanchoe pinnata (Kataka-
taka plant), rhizomes
(ginger) and bulbs (garlic
and onion)
Table 2. Types of Asexual Reproduction in Plants and Animals
Criteria Sexual Reproduction Asexual Reproduction
1. Use of gametes Yes No
2. Use of vegetative parts No Yes
3. Variation of genes in the
gene pool
Yes (There is variation of
genes in the gene pool
because every gamete,
sperm cell and egg cell, has
a unique set of
chromosomes)
No (There is no variation in
the gene pool because the
offspring has an identical
copy of it’s parent’s gene)
Table 3. Comparison of Sexual and Asexual Reproduction
B. Development
Development begins when a zygote is formed and begins to divide. It undergoes the
first stage called embryogenesis. Embryogenesis is the process where a zygote develops
into an embryo. It starts with the formation of a cleavage which are rapid multiple cell
divisions. The cells grow exponentially until it reaches the eight-cell stage known as morula.

14. 10
As the cells continue to divide, they form the blastula, which is a hollow ball of cells where the
cavity is termed as blastocoel. After several mitotic cell divisions, it proceeds to the formation
of a gastrula through gastrulation. Here, three embryonic layers are formed which will
determine the formation of the different parts of the fetus in the later stages. These layers are
stated in Table 4.
Layers Location Systems and parts of the
body derived from it
1. Ectoderm Outermost layer of the
gastrula
• Skin epidermis
• Nervous System
• Jaws and teeth
• Pituitary Gland
• Adrenal Medulla
2. Mesoderm Middle layer of the gastrula • Connective Tissues
• Skeletal System
• Muscular System
• Circulatory System
• Lymphatic System
• Urinary System
• Reproductive
System (not
including cells
which give rise to
sex cells)
• Adrenal Cortex
3. Endoderm Innermost layer of the
gastrula
• Epithelial lining of
digestive,
respiratory and
reproductive
systems
• Parathyroid,
thymus and thyroid
glands
Table 4. Three embryonic layers in gastrula and their derivatives

15. 11
Moreover, plant zygotes undergo somewhat similar processes in embryogenesis. It
also undergoes cleavage and divides asymmetrically into a bigger apical cell and smaller
basal cell. Majority of the plant embryo arises from the apical cell while the basal cell serves
as a suspensor to anchor the developing embryo into the seed. Series of cell divisions occur
in both parts of the embryo. The apical cell divides until it reaches the globular stage, where a
globular head of the embryo is observable in the microscope. It then proceeds to the heart
stage until it develops into a mature embryo. A mature embryo contains two types of apical
meristems, the shoot apical meristem (SAM) and the root apical meristem (RAM). The
shoot apical meristem gives rise to the plants shoot while the root apical meristem, which is
located at the embryo’s radicle, gives rise to the plant’s roots. The radicle serves as the
embryonic root. Cotyledons are also found in the mature embryo, which provides nutrient to
the growing embryo until the plant develops its leaves. The hypocotyl, a structure found below
the cotyledon, gives rise to the plant’s stem.
The second stage of development is organogenesis, where organs start to develop
in the embryo. In animal cells, the three germ layers of the embryo, which are endoderm,
mesoderm, and ectoderm, differentiate and develop into different organs systems and parts
of the body. This is also the time when cells migrate to their final location. In plants however,
this starts when shoot and root apical meristems develop into the corresponding plant parts.
Both apical meristems contain develop into three zones namely zone of cell division, zone of
elongation and zone of differentiation. Zone of cell division is the area where cells are actively
diving. Zone of elongation is the area where cells elongate or grow vertically. Lastly, zone of
differentiation is the area where cells differentiate into different types of cells, according to
what is dictated by its DNA and its location in the plant body. Primary growth occurs in plants
when they grow in height and secondary growth occurs when they grow in width.
The third stage of development is gametogenesis – the formation of gametes or sex
cells. In humans, it occurs during puberty, where its diploid precursors develop into haploid
gametes or sex cells – the mature sperm and egg cells. Female gametogenesis occurs in the
ovaries while male gametogenesis occurs in the testes. In lower plants, gametogenesis
occurs during their gametophytic stage. However, in gymnosperms, this occurs in their
cones and in angiosperms or flowering plants, this occurs in their flowers. Organisms which
develop both male and female gametes are called monoecious or hermaphrodites, while
organisms which develop male and female gametes in separate organisms are called
dioecious.

16. 12
Fig. 2. Plant (photo on the left) and animal (photo on the right) development.
Bees are one of the well-known pollinators. Based on what you have learned
on this module, how can bees help repopulate plants in an area? Discuss the
processes involved and write them on a separate sheet of paper.
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What’s More

17. 13
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What I Have Learned
A. True or false. Identify if the statement is true or false. Write your answer on a separate
sheet of paper.
______1. Gametes are haploid cells.
______2. Double fertilization is observed in lower classes of plants.
______3. The first stage of embryogenesis is the formation of a gastrula.
______4. Pollination occurs when there is a transfer of pollen to the stigma.
______5. Digestive system is derived from the ectoderm.
B. Identification. Identify what is being described on the given statements. Choose your
answer from the words given in the box. Write your answer on a separate sheet of paper.
______1. It is also known as the eight-cell stage in animal embryo development.
______2. These are organisms which can develop both male and female gametes.
______3. The type of reproduction which does not require fertilization to occur.
______4. This is the part of the seed which gives nutrient to the developing zygote.
______5. It is a type of asexual reproduction where an egg cell develops into an adult.
Gastrula Morula
Parthenogenesis Asexual fertilization
Cotyledon Plumule
Hermaphrodites

18. 14
What I Can Do
Some animals are at risk of extinction due to changes in the environment and
decreasing habitat. As a student, a future scientist and/or future environmental scientist, how
can you use your knowledge in reproduction and development to repopulate an area? How
can you advocate on this? Write your answer on a separate sheet of paper.
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Assessment
Directions. Choose the letter of the best answer. Write the chosen letter on a separate sheet
of paper.
1. It is the region of the mature plant embryo which will give rise to the development of
the shoot.
A. Root Apical Meristem C. Shoot Apical Meristem
B. Root Stem Cell D. Shoot Stem Cell
2. It is a type of asexual reproduction where the offspring starts as an outgrowth on the
parent organism then detaches itself when it is already mature.
A. Fragmentation C. Fission
B. Budding D. Parthenogenesis
3. It is a type of asexual reproduction where an unfertilized egg develops into an adult.
A. Fragmentation C. Fission
B. Budding D. Parthenogenesis
4. These are organisms which develop both the male and female gametes or sex cells in
the same organism.
A. Binaries C. Hermaphrodites
B. Dioecious D. Asexual
5. It is the germ layer where the skin epidermis is derived.
A. Endoderm C. Exoderm
B. Ectoderm D. Mesoderm
6. It is the process in development where sex cells are formed.
A. Morphogenesis C. Embryogenesis

19. 15
B. Organogenesis D. Gametogenesis
7. It is a structure developed by a pollen to make way for the transport of sperm cell to
the plant’s egg cell.
A. Pollen tube C. Transport Tube
B. Pollendesmata D. Sperm Tube
8. This is another term which refers to the egg and sperm cells.
A. Blastocyst C. Blastomeres
B. Gametes D. Reproductocytes
9. This a type of fertilization which occurs in flowering plants or angiosperms.
A. Binary Fertilization C. Double Fertilization
B. Diploid Fertilization D. Haploid Fertilization
10. This is known as the embryonic root.
A. Radicle C. Epicotyl
B. Hypocotyl D. Cotyledon
11. It is a series of rapid cell divisions which occurs after a zygote is formed. This gives
rise to 2-cell, 4-cell and 8-cell embryos.
A. Cleavage C. Blastulation
B. Gastrulation D. Migration
12. It is a developmental process which happens when an embryo begins the formation
and development of organs and organ systems.
A. Organogenesis C. Morphogenesis
B. Embryogenesis D. Gametogenesis
13. It is a plant structure which is used to transport sperm cells during pollination. This
structure shields the sperm cell from the harsh conditions of the environment.
A. Pollen tube C. Sperm Case
B. Pollen D. Flagella
14. This is the part of the 2-cell plant embryo which will give rise to almost all of the
developing plant embryo.
A. Suspenser C. Basal Cell
B. Endosperm D. Apical Cell
15. This is a type of asexual reproduction where fragment from an animal regenerates or
develops into a new organism.
A. Budding C. Parthenogenesis
B. Fission D. Fragmentation

20. 16
About 10 years from now, you are part of one of the most prestigious team of
researchers in the Philippines who are focused on developmental biology. Your task
is to increase plant variety. With your knowledge on reproduction and development,
how will you do this project? Write it on a separate sheet of paper.
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Additional Activities

21. 17
What
I
Know
1.
C
6.
B
11.
B
2.
C
7.
B
12.
B
3.
A
8.
D
13.
C
4.
D
9.
A
14.
B
5.
C
10.
D
15.
C
What
I
can
Do
The
answer
depends
on
the
student.
What’s
More
Answer
depends
on
the
student;
however,
it
must
at
least
include
these
phrases:
1.
Bees
pollinate
when
they
feed
on
the
nectar
of
flowers.
Pollens
are
attached
to
the
bee’s
body
hairs
and
are
collected
near
its
legs.
2.
As
bees
feed
on
multiple
flowers’
nectar,
they
facilitate
pollination
3.
When
the
pollen
lands
on
the
female
flower’s
stigma,
it
forms
a
pollen
tube
to
make
way
for
the
two
sperm
cells
to
reach
the
egg
in
contained
in
the
ovary.
Double
fertilization
occurs
as
the
egg
and
the
endosperm
gets
fertilized.
4.
The
zygote
forms
and
develops
into
an
embryo.
What’s
In
1.
Human
reproduction
increases
human
population.
This
is
the
reason
behind
the
increased
population
observed
in
the
graph.
2.
We
can
observe
frog
development
from
a
fertilized
egg
cell
or
zygote
to
an
adult
frog.
A
zygote
undergoes
cell
division
and
cell
differentiation
to
be
an
adult
frog.
What’s
New
Across:
1.
Fertilization
2.
Embryogenesis
3.
Embryo
4.
Mitosis
Down:
1.
Fragmentation
6.
Differentiation
7.
Organogenesis
8.
Embryogenesis
What
I
have
learned
True
or
False
1.
True
2.
False
3.
False
4.
True
5.
False
Identification
1.
Morula
2.
Hermaphrodite
3.
Asexual
Reproduction
4.
Endosperm
5.
Parthenogenesis
Assessment:
1.
C
6.
D
11.
A
2.
B
7.
A
12.
A
3.
D
8.
B
13.
B
4.
C
9.
C
14.
D
5.
B
10.
A
15.
D
Additional
Activity
The
answer
depends
on
the
student.
Answer Key

22. 18
References
Reece, JB, Urry LA, Wasserman SA, Minorsky PV and Jackson RB. 2011. Campbell’s
Biology. (10th edition). Benjamin Cummings. 820-838 pp.
Reece, JB, Urry LA, Wasserman SA, Minorsky PV and Jackson RB. 2011. Campbell’s
Biology. (10th edition). Benjamin Cummings. 1017-1053 pp.
Evert, RF. 2006. Esau’s Plant Anatomy: Meristems, Cells, and Tissues of the Plant Body –
Their Structure, Function and Development. (3rd edition). John Wiley and Sons. 25 pp.
https://psa.gov.ph/sites/default/files/ird/popcen_graph_2.png
https://www.khanacademy.org/science/biology/developmental-biology/signaling-and-
transcription-factors-in-development/a/frog-development-examples
https://vivadifferences.com/difference-between-pollination-and-fertilization-in-flowering-
plants/
https://www.brainyias.com/animals-reproduction/

23. For inquiries or feedback, please write or call:
Department of Education – Division of San Jose Del Monte City –
Learning Resource Management Section (LRMS)
San Ignacio Street, Poblacion, City of San Jose Del Monte, Bulacan
Email Address: lrmssdosjdmc@gmail.com
This material was contextualized and localized by the
Learning Resource Management Section (LRMS)
SCHOOLS DIVISION OF SAN JOSE DEL MONTE
MERLINA P. CRUZ PhD, CESO VI
Officer-in-Charge
Office of the Schools Division Superintendent
ERICSON S. SABACAN EdD, CESO VI
Assistant Schools Division Superintendent
ROLANDO T. SOTELO DEM
Chief Education Supervisor
Curriculum Implementation Division
ANNALYN L. GERMAN EdD
Education Program Supervisor, LRMS
ESPERANZA D. ESPAŇOLA
Education Program Supervisor, Science
EUNICE ANNE C. JARAMILLO
CSJDM National Science High School – Senior High Writer
MELINDA F. OJEDA
CSJDM National Science High School
Language Reviewer
ROMELYN T. ASIS
CSJDM National Science High School – Senior High Content Language Editor