What is an ecosystem?
A fundamental unit in nature comprising living organisms and their non-living environment.
What is the primary source of energy in an ecosystem?
The sun.
What are decomposers?
Organisms that feed on dead or decaying matter and recycle nutrients.
Name two categories of decomposers.
Macro-decomposers (e.g., mushrooms) and Micro-decomposers (e.g., bacteria).
How do decomposers break down organic matter?
By releasing enzymes onto organic matter, breaking it into simpler compounds.
List one importance of decomposers.
Enriching soil with nutrients for plant growth.
What are autotrophs?
Organisms that create their own food using inorganic substances.
Give an example of autotrophs.
Green plants and algae.
What are heterotrophs?
Organisms that rely on organic matter from other organisms for energy.
Who are primary consumers?
Herbivores that feed directly on producers.
Who are secondary consumers?
Carnivores that eat primary consumers.
Who are tertiary consumers?
Predators that consume secondary consumers.
What is a food chain?
A linear sequence of organisms where energy is transferred through feeding.
Provide an example of a food chain.
Grass → Grasshopper → Toad → Snake → Hawk.
What is a food web?
A network of interconnected food chains.
How do human activities disrupt food webs?
Through over-harvesting and introducing foreign species.
What are ecological pyramids?
Diagrams representing relationships within ecosystems.
What does the Pyramid of Numbers represent?
The number of organisms at each trophic level.
What does the Pyramid of Biomass show?
The total mass of organisms at each trophic level.
What does the Pyramid of Energy depict?
Energy flow through trophic levels over time.
What does the first law of thermodynamics state?
Energy cannot be created or destroyed, only transformed.
What does the second law of thermodynamics state?
Energy conversion results in energy loss as heat.
How does the first law apply to ecosystems?
Total energy remains constant during transfers between trophic levels.
How does the second law affect energy flow?
Energy is lost as heat at each trophic level, limiting energy for higher levels.
Why is energy not cyclical in ecosystems?
It cannot return to its source and is lost as heat.
What percentage of energy transfers to the next trophic level?
Approximately 10%.
What role does carbon dioxide play in ecosystems?
It is necessary for photosynthesis.
Name a waste management function of decomposers.
Assisting in sewage disposal.
What is an example of a macro-decomposer?
Mushrooms.
What is an example of a micro-decomposer?
Bacteria.
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