Ecosystem Thinking
A pond has fish, algae, insects, water, and rocks. Is this an ecosystem? Why?
Yes — it includes living and nonliving things interacting.
Mushrooms grow on a fallen tree and break it down. What role are they playing?
Decomposer
Grass → rabbit → fox. What is the rabbit’s role?
Consumer / herbivore / primary consumer
Bees get nectar and flowers get pollinated. What relationship is this?
Mutualism
What is the difference between threatened and endangered?
Threatened = at risk; endangered = very close to extinction.
If all the plants in a field died, which group would be affected first — producers, consumers, or decomposers? Why?
Consumers — they lose their food source.
A deer eats grass and berries. What type of consumer is it?
Herbivore
In a food web, an owl eats mice and snakes. What happens if the mice population drops?
Owls may decrease or switch food sources.
A barnacle attaches to a whale and gets a ride. The whale is not harmed.
Commensalism
If a law protects a bird’s nesting area, what is this an example of?
Remediation/protection program
A new plant species is added to a meadow and grows quickly. What could happen to the animals there?
Animal populations may increase because there is more food.
A bear eats fish and plants. What type of consumer is it?
Omnivore
Why is a food web more stable than a single food chain?
Organisms have more than one food source.
A flea lives on a dog and drinks its blood.
Parasitism
Why do scientists track endangered species populations?
To see if protection efforts are working.
If pollution kills most of the insects in an ecosystem, what might happen to frogs that eat them?
Frog population would likely decrease.
If decomposers disappeared, what would pile up in the environment?
Dead plants and animals
If the producer level decreases, what happens to the rest of the food web?
All higher levels are affected and may decrease.
Two organisms both benefit. What must be true about their survival chances?
Both are helped and may survive better together.
If a predator becomes endangered, what might happen to its prey?
Prey population may increase.
Why is removing one species from an ecosystem risky?
It can disrupt the food web and affect many other organisms.
Why are producers necessary at the start of every food chain?
They create the energy (food) for all other organisms.
A student says energy goes from fox → rabbit → grass. What is wrong?
Energy flows grass → rabbit → fox.
A parasite is removed from an ecosystem. What might happen to the host species?
It may become healthier or increase.
Give one human activity that can cause species to become endangered.
Habitat loss / pollution / overhunting / climate change