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SCIENCE
Quarter 3 - Module 7 ECOSYSTEM: BIODIVERSITY
Science – Grade 10 Support Material for Independent Learning Engagement (SMILE) Quarter 3 – Module 7: Ecosystem: Biodiversity First Edition, 2021 Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government
of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for the exploitation of such work for a profit. Such agency or office may, among other things, impose as a condition the payment of royalties. Borrowed materials (i.e., songs, stories, poems, pictures, photos, brand names, trademarks, etc.) included in this module are owned by their respective copyright holders. Every effort has been exerted to locate and seek permission to use these materials from their respective copyright owners. The publisher and authors do not represent nor claim ownership over them.
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Office Address: Purok Farmers, Olingan, Dipolog City
ZamboangadelNorte, 7100
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Leo Martinno O. Alejo - Project Development Officer II, LRMS
Arsenia C. Zamoras - Public Schools District Supervisor
Jovencia M. Samante - Public Schools District Supervisor
Jose Rey A. Adriatico - School Principal, Pamansalan ETHS
Joselito S. Tizon - School Principal, Galas NHS
What I Need to Know In this module, you will learn how the diversity of species increases the probability of
adaptation and survival of organisms in a changing environment. You will also learn about the
relationship between population growth and the carrying capacity of a specific environment. You
will become aware of the numerous human activities that have detrimental effects on the
environment and suggest initiatives that aim to protect and preserve your community's
biodiversity.
Most Essential Learning Competency
1. Explain how species diversity increases the probability of adaptation and survival of
organisms in changing environments. ( S10LTIIh-41)
2. Explain the relationship between population growth and carrying capacity.
(S10LTIIIi-42)
What's In
In the previous lesson, you learned about the organism's ability to adapt and survive in a
given environment. Let us have a quick review of these concepts.
Activity1. Identify by Pictures!
Directions: Tell whether each picture shows adaptation or survival. Write your answer in the
space provided.
Activity 2: Let's Talk About Them!
Direction: Write T if the statement is True, F if the statement is false.
__________ 1. Increased genetic diversity leads to decreased chance of species survival. __________ 2. The more recent loss of biodiversity has been attributed primarily to human activities such as overfishing, overhunting, and loss of habitat. __________ 3. Greater biodiversity promotes a more stable ecosystem. __________ 4. Biodiversity refers to a group of organisms of the same species that live in a certain area. _________ 5. A species has a direct economic value if there are benefits produced by the an organism without using them.
Activity 3: Match Up!
Directions: Match column A with column B. Write the letter of the correct answer in the space
provided before each number.
Column A Column B
_______ 1.Density-dependent A. It gives us an idea of how fast a
population changes over time.
population’s growth
_______ 3. Emigration C. Refers to the number of organisms per
unit area.
_______ 4. Population density D. Can be defined as a species' average
population size in a particular habitat.
_______ 5. Predation E. Individual organisms leave and go to a
new area where they can find enough
resources for survival and reproduction
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What is it
Biodiversity and Stability
Biodiversity is a term that describes how varied living things are in a specific area.
Organisms are part of biodiversity and may be economically and ecologically valuable. Their
products are sources of food, medicine, clothing, shelter and energy. These organisms are also
important in maintaining balance in the ecosystem as they perform their specific roles. Some
species maintain the quality of natural bodies of water; some prevent soil erosion and floods, cycle
materials in the soil, and absorb pollutants. Others feed on insects and pests, which control the
population of organisms in a certain environment, thus making the ecosystem balance and stable.
The value of species can be divided into various categories:
1. Direct economic value
The species is considered to have direct economic value if their products are sources
of food, medicine, clothing, shelter, and energy. For example, some medicines being used
nowadays have formulations extracted from plants or animals. Another common plant,
Vitexnegundo (Lagundi), is extracted for cough syrup production.
2. Indirect economic value
A species has an indirect economic value if there are benefits produced by the
organism without using them. For example, certain species maintain the chemical quality
of natural bodies of water, prevent soil erosion and floods, cycle materials in the soil, and
absorb pollutants.
3. Aesthetic value
Many species provide visual or artistic enjoyment, like a forested landscape and the
calming beauty of a natural park, or they may be used for spiritual meditation like the
prayer mountains.
Biodiversity is very important because it sustains through the flow of energy, the food web
on earth, and contributes to environmental stability.
Stability of an ecosystem can be described as the resilience to withstand changes that may occur
in the environment. Many changes occur in the environment resulting from natural or human
activities. These changes may severely reduce biodiversity and result in the instability of the
ecosystem.
Population density refers to the number of organisms per unit area. If a population density is
very high, that means there are many organisms crowded into a certain area. If a population's
density is low, that means there are very few organisms in an area.
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Population
A population can be defined as the number of all individuals belonging to the same group
or species that live in a particular area and interbreed with one another to form offspring.
When it comes to humans, the population may refer to the collective number of human
individuals.
The science that focuses on the characterization and statistical analysis of the human
population refers to demography.
o It aims to provide a comprehensive census that collects, analyzes, compiles, and
publishes all necessary information regarding the characteristics of the human
population in a certain region.
Population Growth
Population growth is the increase in the number of individuals in a population.
A population may increase if resources, such as food, water, and shelter, are readily
available.
Population growth is often related to the biotic potential of organisms. This is the capacity
of an individual or population to reproduce under ideal conditions—sufficient food supply,
no predators, and a lack of disease.
o In general, large organisms, such as elephants and whales, have low biotic potentials,
whereas small organisms, such as insects and bacteria, have high biotic potentials.
Types of Population Growth
exponential and logistic growths.
as time goes on.
shaped curve.
resources are available, and there is little to no
competition, predation, and disease. This is not the
case in the real world because species compete for
limited resources.
the water.
water green. Image Source: https://www.cleveland.com/news/2020/05/ lake-erie-harmful-algal-bloom-is-expected-to-be-
Carrying capacity determines the maximum population
size of a species that the ecosystem can sustain with its natural
resources. It influences the population size as well as birth rates,
death rates, and movement of species. A population increases
and has an exponential growth when the resources are not
limited. This exponential growth will turn to logistic growth as it
encounters environmental resistance.
resistance can be visualized using the spilling bucket diagram.
The water put into the bucket is like the production of the things
put into the ecosystem. When the bucket is all full, it is like an
ecosystem that has met its carrying capacity. When the bucket reaches the top, the rest of the
water coming in "overflow", like when an ecosystem overpopulates. If you do not want to "overflow"
your ecosystem, you stay under the carrying capacity.
The Three Aspects of Biodiversity Measurement
a. Ecosystem Diversity refers to the number of ecosystems that are present in a location. b. Species Diversity refers to a variety of species in a given ecosystem. c. Genetic Diversity refers to the variations in genes between individuals of a species.
A factor that regulates a population's growth and is
influenced by population density is called a density-dependent
limiting factor. If the population's density does not directly
influence changes in population growth, then it is called a density-
independent limiting factor.
down population growth.
The plot of population size vs. time is an S-shaped
curve with the first part of the graph similar to that for
exponential growth.
individuals and plentiful resources. However, when the
number of individuals becomes large enough, the
resources are depleted, and the growth rate slows
down. Eventually, the growth rate levels off as the
carrying capacity is reached.
culture plate.
Spilling Bucket Diagram Image Source: https://ecologyforstudents.
Limiting Factors that depend on population density
1. Diseases and parasites. Infectious diseases and parasites spread faster in densely
populated areas. (Image 1)
2. Competition for resources. The organism with better adaptations to obtain (food)
resources will be able to reproduce more often, and its population will grow. The organisms
that have limited abilities to compete for the resources will not reproduce as often, may not
be fit enough to live long, and can cause their population to decrease. (Image 2)
3. Predation. Plenty of prey are available; predators will be able to eat sufficiently, thus have
the energy to reproduce much and increase their numbers. The population of their prey will
begin to decrease as more and more of them are eaten. However, the predator population
will eventually reach carrying capacity. There will not be enough prey for all of the predators
in the population, since the predators themselves compete for their "prey" resource. As the
number of prey decreases, so will the number of predators because there is not enough food
to sustain them. (Image 3)
4. Emigration. It occurs when, as a population approaches its carrying capacity, and
individual organisms leave and go to a new area where they can find enough resources for
survival and reproduction. This will obviously cause a decrease in the number of organisms
in a population. (Image 4)
(1) (2)
Activity 4A. Dependent or Independent?
Directions: Read each situation in the table below, then state if it is a density-independent
limiting factor or a density-dependent factor. Indicate the specific limiting factor that is
occurring.
biology class. Because the room was
crowded, the five students were asked
to go to the curriculum chairperson to
change their schedule.
many aquatic organisms in the vicinity.
A new strain of Dengue virus breaks
out in the country.
residents to leave Leyte.
lizards in Barangay Linabo causes a
decrease in the population of
mosquitoes.
Activity 4B. Population Growth & Carrying Capacity
Directions: Study the given figure and answer the questions below. You may use a separate sheet of paper for your answers.
1. The two Paramecium species were grown alone
then grown together in a culture. Based on the
graphs, what can you conclude about the
population density when they are grown
separately?
each paramecium reach its carrying
capacity?
populations were grown together.
5. What happens to a population when they exceed
their carrying capacity?
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What I Have Learned Activity 5. Fill Me! Direction: Complete the statements below by filling in with the correct word(s) found in the box.
biodiversity direct economic value density-independent limiting factor
population density population growth density-dependent limiting factor
diseases and parasites carrying capacity indirect economic value stability
1. ___________________ gives us an idea on how fast a population changes over time.
2. _______________________ of an ecosystem can be described as the resilience to withstand
changes that may occur in the environment.
3. If the population’s density does not directly influence changes in population’s growth,
then it is called a _______________________________.
4-5. A factor that regulates a population’s growth and is influenced by
_______________________ is called ______________________________.
6. The species is considered to have _____________________________ if their products are
sources of food, medicine, clothing, shelter, and energy.
7. __________________________ is the key indicator of the health of an ecosystem.
8. A species has a/an __________________________________ if there are benefits produced by
the organism without using them.
9. ________________________________ are limiting factors that spread faster in densely
populated areas.
10.____________________ determines the maximum population size of a species that the
ecosystem can sustain with its natural resources.
What I Can Do
Activity 6: Make a Choice!
Directions: Look at the given example in each item. Select the best way to use each of the
resources in order to conserve it. Write a brief explanation of your choice. Refer to the rubric for
your guidance in presenting your answer.
1. Coral Reef
b. Collect coral fishes and sell them to pet shops.
c. Collect corals as souvenir items for tourists.
Answer: ____________________________________________________________________________
a. Convert it into an industrial area.
b. Build a community where houses are built among the trees.
c. Turn it into a jogging area.
Answer: ____________________________________________________________________________
b. Get only minor forest products.
c. Advertise it as a camping site.
Answer: ____________________________________________________________________________
Assessment
Direction: Read each item carefully and choose the letter of the correct answer. Circle the letter of the best answer.
1. Which of the following causes a decreasing wildlife population in most of the places in our
country?
B. Loss of limiting factor
C. Loss of carrying capacity
D. Loss of natural disturbances
2. Davao is known for its wide variety of fruits and other plant species that makes it really
attractive to tourists. Which of the following classification of biodiversity value is described?
A. Indirect economic value
B. Direct economic value
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Content
Concept is somewhat
There are more than 5 spelling, punctuation or grammar errors
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3. Lino breeds white mice in a cage. After a few generations, the breeder observes that the
white mice are more aggressive towards each other, the young are less healthy, and more
young white mice die. What do you think will happen to the population of white mice?
A. The population will remain the same.
B. The population is not affected.
C. The population will decrease.
D. The population will increase.
4. Cocolisap infestation outbreak has been declared in some parts of the Philippines. The
cocolisap feeds on the sap of the coconut tree and injects toxic enzymes, resulting in
discolored leaves and deformed plant tissues that retard its growth of coconut tree. This,
results in a decrease of the survival rate of coconut trees. Which of the following factors
limits the population of coconut trees?
A. Predation
B. Emigration
C. Diseases and parasites
D. Competition for resources
5. What is adaptation? It is a physical or behavioral characteristic that helps _____
A. a plant grow
D. plant and animals to reproduce
6. If the number of births in a population is the same as the number of deaths in a population,
what will happen to the growth of the population?
A. It will increase.
B. It will decrease.
D. It will fluctuate.
7. Why would advances in medicine lead to population growth?
A. Treatment of deadly diseases allows people to live longer
B. People are unable to have babies without medical help
C. Babies do not grow if they don't take their medicines
D. Drugs allow mothers to have multiple births, like octuplets.
8. What is the carrying capacity of the given graph?
A.1000 B. 800 C. 8000 D. 600
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9. When a population grows past the ecosystem's carrying capacity,
what happens to the population?
A. It continues to grow
B. It starts to die off to return to carrying capacity
C. It will go extinct due to lack of resources
D. It grows then finds a new carrying capacity
10. The largest number of individuals in a species that an environment can support long term.
A. carrying capacity
D. population density
Additional Activities Directions: Write an essay on the effects of human activity on the biodiversity of your community.
Be guided by the following questions in writing your output.
1. How is biodiversity adversely affected by human activity?
2. What specific activities do you suggest to reduce these negative effects?
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Concept is evident
Concept is acceptable
Concept is limited
spelling, punctuation or
Department of Education Republic off the Philippines (2009).Importance of Biodiversity.
Environmental Issues, Problems and Solutions. In Biology Textbook (pp 326-327; 344- 346) Mandaluyong City, Philippines. Book Media Press Inc.
Dispezio, M. et. al( (1996). Diversity and adaptation.In Science Insights Exploring Living Things
(p139). United States of America: Addison. Wesley Publishing Company Glencoe. (2000), Ecology. In Biology The Dynamics of Life (p 94; 114). USA= McGraw-Hill
Companies. Quipper. (n.d.). Retrieved from https://www.quipper.com/ph/ Ravago, L. (2010) Philippines as Megadiversity Country. In Functional Biology (2nd ed., pp 409-
410). Quezon City Philippines: Vibal Publishing House
Here the breezes gently Blow,
Here the birds sing Merrily,
The liberty forever Stays,
With the Yakans in unity
Gallant men And Ladies fair
Linger with love and care
Golden beams of sunrise and sunset
Are visions you’ll never forget
Oh! That’s Region IX
Hardworking people Abound,
All of them are proud and true
Region IX our Eden Land
Region IX
Our..
Eden...
Land...
My Final Farewell Farewell, dear Fatherland, clime of the sun caress'd
Pearl of the Orient seas, our Eden lost!,
Gladly now I go to give thee this faded life's best,
And were it brighter, fresher, or more blest
Still would I give it thee, nor count the cost.
On the field of battle, 'mid the frenzy of fight,
Others have given their lives, without doubt or heed;
The place matters not-cypress or laurel or lily white,
Scaffold or open plain, combat or martyrdom's plight,
T is ever the same, to serve our home and country's need.
I die just when I see the dawn break,
Through the gloom of night, to herald the day;
And if color is lacking my blood thou shalt take,
Pour'd out at need for thy dear sake
To dye with its crimson the waking ray.
My dreams, when life first opened to me,
My dreams, when the hopes of youth beat high,
Were to see thy lov'd face, O gem of the Orient sea
From gloom and grief, from care and sorrow free;
No blush on thy brow, no tear in thine eye.
Dream of my life, my living and burning desire,
All hail ! cries the soul that is now to take flight;
All hail ! And sweet it is for thee to expire ;
To die for thy sake, that thou mayst aspire;
And sleep in thy bosom eternity's long night.
If over my grave some day thou seest grow,
In the grassy sod, a humble flower,
Draw it to thy lips and kiss my soul so,
While I may feel on my brow in the cold tomb below
The touch of thy tenderness, thy breath's warm power.
Let the moon beam over me soft and serene,
Let the dawn shed over me its radiant flashes,
Let the wind with sad lament over me keen ;
And if on my cross a bird should be seen,
Let it trill there its hymn of peace to my ashes.
Let the sun draw the vapors up to the sky,
And heavenward in purity bear my tardy protest
Let some kind soul o 'er my untimely fate sigh,
And in the still evening a prayer be lifted on high
From thee, 0 my country, that in God I may rest.
Pray for all those that hapless have died,
For all who have suffered the unmeasur'd pain;
For our mothers that bitterly their woes have cried,
For widows and orphans, for captives by torture tried
And then for thyself that redemption thou mayst gain
And when the dark night wraps the graveyard around
With only the dead in their v igil to see
Break not my repose or the mystery profound
And perchance thou mayst hear a sad hymn resound
'T is I, O my country, raising a song unto thee.
And even my grave is remembered no more
Unmark'd by never a cross nor a stone
Let the plow sweep through it, the spade turn it o 'er
That my ashes may carpet earthly f loor,
Before into nothingness at last they are blown.
Then will obliv ion bring to me no care
As over thy vales and plains I sweep;
Throbbing and cleansed in thy space and air
With color and light, with song and lament I fare,
Ever repeating the faith that I keep.
My Fatherland ador'd, that sadness to my sorrow lends
Beloved Filipinas, hear now my last good-by!
I give thee all: parents and kindred and friends
For I go where no slave before the oppressor bends,
Where faith can never kill, and God reigns e'er on high!
Farewell to you all, from my soul torn away,
Friends of my chi ldhood in the home dispossessed!
Give thanks that I rest from the wearisome day!
Farewell to thee, too, sweet friend that lightened my way;
Beloved creatures al l, farewell ! In death there is rest !
I Am a Filipino, by Carlos P. Romulo I am a Filipino–inheritor of a glorious past, hostage to the uncertain
future. As such I must prove equal to a two-fold task–the task of
meeting my responsibility to the past, and the task of performing
my obligation to the future.
I sprung from a hardy race, child many generations removed of
ancient Malayan pioneers. Across the centuries the memory comes
rushing back to me: of brown-skinned men putting out to sea in
ships that were as frail as their hearts were stout. Over the sea I see
them come, borne upon the billowing wave and the whistling wind,
carried upon the mighty swell of hope–hope in the free abundance
of new land that was to be their home and their children’s forever.
I am a Filipino. In my blood runs the immortal seed of heroes–seed
that flowered down the centuries in deeds of courage and defiance.
In my veins yet pulses the same hot blood that sent Lapulapu to
battle against the first invader of this land, that nerved Lakandula
in the combat against the alien foe, that drove Diego Silang and
Dagohoy into rebellion against the foreign oppressor.
The seed I bear within me is an immortal seed. It is the mark of my
manhood, the symbol of dignity as a human being. Like the seeds
that were once buried in the tomb of Tutankhamen many thousand
years ago, it shall grow and flower and bear fruit again. It is the
insignia of my race, and my generation is but a stage in the
unending search of my people for freedom and happiness.
I am a Filipino, child of the marriage of the East and the West. The
East, with its languor and mysticism, its passivity and endurance,
was my mother, and my sire was the West that came thundering
across the seas with the Cross and Sword and the Machine. I am of
the East, an eager participant in its spirit, and in its struggles for
liberation from the imperialist yoke. But I also know that the East
must awake from its centuried sleep, shake off the lethargy that has
bound his limbs, and start moving where destiny awaits.
I am a Filipino, and this is my inheritance. What pledge shall I give
that I may prove worthy of my inheritance? I shall give the pledge
that has come ringing down the corridors of the centuries, and it
shall be compounded of the joyous cries of my Malayan forebears
when first they saw the contours of this land loom before their eyes,
of the battle cries that have resounded in every field of combat from
Mactan to Tirad Pass, of the voices of my people when they sing:
“I am a Filipino born to freedom, and I shall not rest until freedom
shall have been added unto my inheritance—for myself and my
children and my children’s children—forever.”