Science 7-Tapestry of Ecosystem and Interdependence

Science

1. The Living Tapestry:
Understanding Ecosystems and
Interdependence
Nature weaves a complex and beautiful tapestry called the ecosystem, where life thrives
in an intricate balance. An ecosystem comprises biotic factors, which include all living
organisms such as plants, animals, fungi, and bacteria, and abiotic factors, which are non-living
elements like sunlight, temperature, water, soil, and minerals. These components do not exist in
isolation; rather, they constantly interact, forming a dynamic system where each factor plays a
vital role. The abundance or absence of one can have a ripple effect on the entire ecosystem.
In a lush tropical rainforest, for instance, the towering trees (biotic) provide shelter and
food for birds, insects, and mammals, while the humidity and rainfall (abiotic) ensure the
survival of mosses and fungi on the forest floor. The sunlight filters through the canopy, driving
photosynthesis in plants and forming the base of the food chain. These seemingly small
interactions create a huge impact. Without sufficient light or water, photosynthesis slows down,
and the food web begins to collapse.
At the heart of this system lies the food web, a complex network of who eats whom.
Producers like plants and algae use abiotic elements such as sunlight and water to create
energy-rich food. Herbivores, or primary consumers, feed on these producers, while secondary
consumers (like small carnivores) eat the herbivores. At the top of the web are tertiary
consumers—predators that have few or no enemies. Decomposers like fungi and bacteria
break down dead organisms, returning nutrients to the soil and completing the cycle. This
interdependence keeps energy flowing and ecosystems thriving.
Disruption to any part of this web can cause a domino effect. If a keystone species—a
species on which many others depend—goes extinct due to pollution, climate change, or
hunting, other species may follow. For example, if bees (pollinators) disappear, many plants will
fail to reproduce, affecting herbivores and, eventually, carnivores. Such imbalance leads to
ecosystem degradation and the loss of biodiversity, showing how fragile yet essential each
organism's role is.
In urban areas, ecosystems exist too—parks, gardens, rivers, and even street trees. The
presence of birds controlling pests, worms aerating the soil, and native plants improving air
quality demonstrates the same interconnectedness. Human intervention through conservation,
reforestation, and sustainable living practices can help restore balance where it is lost. By
recognizing our role in the food web, we become more responsible stewards of the Earth.
Ultimately, ecosystems are not only biological systems but lessons in unity and survival.
They teach us that life does not thrive in isolation. Every drop of water, every ray of light, and
every tiny creature plays a part in sustaining life. To disrupt this harmony is to endanger the
future. Therefore, understanding and protecting ecosystems is more than a scientific endeavor
—it is a moral responsibility.
Guide Questions

2. 1.List down the biotic and the abiotic factors mentioned in the article. Analyze how a
change in one abiotic factor (e.g., temperature or rainfall) could indirectly affect top
predators in an ecosystem.
Biotic Factors (Living components)
a.Plants
b.Herbivores (e.g., deer, rabbits)
c.Carnivores or top predators (e.g., lions, eagles, wolves)
d.Decomposers (e.g., fungi, bacteria)
e.Parasites
Abiotic Factors (Non-living components)
a.Temperature
b.Rainfall (precipitation)
c.Sunlight
d.Soil quality
e.Water availability
f.Air/wind
g.Climate
h.pH levels
i.Humans
2.Evaluate the role of decomposers in maintaining the sustainability of ecosystems. What
might happen if decomposers were removed?
Answer:
Decomposers are essential for ecosystem sustainability. They maintain nutrient balance,
support plant growth, and keep the environment clean and functional. Without them, the entire
food web would eventually collapse, demonstrating their vital role in maintaining life on Earth.
3.Create a simple food web using organisms found in a local habitat. Predict what might
happen if one species in the web becomes extinct.

Conclusion:
Each organism in a food web plays a role in maintaining ecological balance. The
extinction of even one species, like the grasshopper, can set off a chain reaction that affects
multiple organisms in both upward and downward directions within the food web. This
highlights the importance of biodiversity and conservation in every habitat.
4.Compare and contrast food chains and food webs. Why are food webs considered more
accurate models of real ecosystems?
Answer:

3. Aspect Food Chain Food Web
Definition
A linear sequence showing one path of
energy flow
A complex network showing
multiple paths of energy flow
Structure
Straight line: one organism per level (e.g.,
grass grasshopper frog snake)
→ → →
Interconnected lines showing
various organisms at each level
Simplicity Simple and easy to understand More complex and detailed
Organism
Role
Each organism has only one role (e.g., only
a predator or only prey)
Organisms can have multiple roles
(e.g., omnivores)
Realism Less realistic; oversimplified
More realistic; reflects natural
feeding relationships
Impact of
Changes
Limited—change affects one path only
Broad—change in one species
affects multiple organisms
Why Are Food Webs More Accurate Models of Real Ecosystems?
Food webs are considered more accurate because they show the complex interactions
between multiple species in an ecosystem. In reality, most organisms eat and are eaten by
more than one kind of organism. For example, a frog might eat insects, but also be eaten by
snakes and birds. These interconnected relationships are better represented in a food web than
a single food chain.
Food webs also demonstrate the stability and interdependence of ecosystems. When one
species is removed or affected, the food web shows how it can impact several other species, not
just one. This complexity helps scientists and ecologists better understand the balance of
ecosystems and how to manage or protect biodiversity.
Conclusion:
While food chains are useful for basic understanding, food webs provide a complete and
more realistic picture of how energy and nutrients flow through an ecosystem. They highlight
the interconnectedness of life, showing that no species exists in isolation.
5.Propose a solution to restore balance in an ecosystem that has been damaged by human
activity.
Answer:
To restore balance in a damaged ecosystem, one effective solution is reforestation and
community involvement. Planting native trees helps bring back wildlife habitats and improves
soil and air quality. Controlling pollution by managing waste and reducing harmful chemicals
also protects water and land resources. Protecting wildlife through sanctuaries and
reintroducing native species helps maintain the food chain. Most importantly, educating and
involving local communities ensures long-term care and sustainable use of natural resources.
With these combined efforts, ecosystems can slowly recover and thrive again.
6.Infer the relationship between biodiversity and ecosystem resilience. Why might a more
diverse ecosystem be better able to withstand environmental changes?
Answer:
Biodiversity helps ecosystems become more resilient to environmental changes. When
an ecosystem has many different species, it is more stable because if one species is lost or
affected, others can take over its role. This prevents the whole system from collapsing. In
contrast, ecosystems with low biodiversity are more fragile and easily disrupted. So, a more

4. diverse ecosystem can better adapt, recover, and survive during changes like droughts,
diseases, or human disturbances.