Ecosystems Basics
What is an ecosystem?
All interacting parts of a biological community.
What is a producer?
A producer is an organism that makes its own food using sunlight (plants, algae).
What process do plants use to take in carbon dioxide and make energy?
Photosynthesis.
Define mutualism.
Mutualism = both organisms benefit.
What is sustainability?
Sustainability = meeting needs now without harming future generations’ ability to meet theirs.
Explain the difference between biotic and abiotic.
Biotic factors = living things
Abiotic factors = nonliving things
Explain how energy flows through a food chain.
Energy flows from the sun → producers → consumers → decomposers, and is lost as heat at each step.
Describe how water moves from plants back into the atmosphere.
Transpiration—plants release water vapour through leaves.
Explain the difference between primary and secondary succession.
Primary succession starts with no soil (ex: bare rock).
Secondary succession starts with soil already present (ex: after a fire).
Explain the difference between a need and a want with an example for each.
Need: something essential (water, shelter).
Want: extra/nonessential (iPhone, fast food).
Identify three biotic and three abiotic factors on the school grounds.
Answers may vary:
Biotic: trees, grass, birds
Abiotic: sunlight, soil, rocks
Create a 4-organism food chain using real organisms and identify each level
Example:
Grass (producer) → Grasshopper (primary consumer) → Frog (secondary consumer) → Snake (tertiary consumer)
Explain the difference between evaporation, transpiration, and condensation, and where these would be found on a water cycle diagram.
A volcano has just erupted and created new volcanic rock. Is this an example of primary or secondary succession?
Primary succession
Your school wants to build a new parking lot. List two environmental impacts this could cause.
Habitat loss
Increased runoff
Less biodiversity
Soil compaction
A forest suddenly experiences a drastic decrease in temperature. Analyze how one biotic and one abiotic factor might be affected.
Answers may vary:
A drop in temperature (abiotic) could cause plants to die (biotic).
Animals might migrate or struggle to survive due to reduced food/energy.
If the primary consumer population decreases, analyze what will likely happen to both the producer and secondary consumer populations.
Producers increase (less eaten)
Secondary consumers decrease (less food available)
Analyze how increased air pollution could affect both the water cycle and plant growth.
More pollution → acid rain → damage to plants and soil.
Pollutants in water cycle spread contaminants → affects plant growth.
Analyze how the removal of a predator might change the entire ecosystem.
Analyze how the removal of a producer might change the entire ecosystem
Prey population to increase
Overgrazing/overpopulation
Plant populations decrease
Entire food web becomes unbalanced
Analyze how invasive species can disrupt food webs. and give an example. Are introduced species always invasive?
They outcompete native species.
This disrupts the entire food web.
Describe three biotic and three abiotic factors what are required in an ecosystem.
For each factor, explain how it interacts with at least one other factor to maintain ecosystem stability.
Answers may vary
Abiotic: temperature, water, light, soil
Biotic: plants, animals, bacteria
Evaluate which is more important for ecosystem stability: decomposers or producers. Defend your choice.
Acceptable answers defend one:
Producers because they start all food chains.
Decomposers because they recycle nutrients back to the soil.
Evaluate whether human activity or natural disturbances (like volcanic eruptions) have a greater effect on the carbon cycle. Support your reasoning.
Answers vary but may include:
Humans produce constant carbon emissions (vehicles, industry).
Natural events are large but short-term.
Student must argue which has greater impact.
Describe three symbiotic relationship examples using organisms of your choice. Explain the interaction.
Mutualism: bee & flower
Commensalism: bird nesting in a tree
Parasitism: tick on a deer
Propose a realistic plan your community could implement to reduce your environmental impact, and evaluate why it would be effective.
Reduce waste
Use public transit
Energy-efficient homes
Recycling programs
Students must justify how the action lowers footprint (less energy, less waste, etc.).