Food Chains
What is the first organism in every food chain?
A producer
The relationship where both organisms benefit is called...
Which trophic level contains the most energy?
Producers
What is it called when an ecosystem stays balanced over time?
Equilibrium
Name one abiotic factor in an ecosystem.
Sunlight, water, temperature, soil, etc.
In this food chain: Grass - Grasshopper - Frog - Snake - Hawk, what is the secondary consumer?
A barnacle living on a whale, without harming it, is an example of...
Commensalism
10%
What happens to predators if prey disappear?
Predator numbers decrease
What is biodiversity?
The variety of living things in an area.
What do arrows in a food chain represent?
The direction of energy flow
A tapeworm living in a dog's intestine is...
Parasitism
If a producer has 10,000kcal, how much energy will the secondary consumer have?
100kcal
Give an example of a short-term change in an ecosystem.
Forest fire, flood, drought, etc.
Why are decomposers important?
They recycle nutrients into the soil for producers
Fungi, bacteria, earthworms, etc.
Give an example of predation in a pond ecosystem.
Frog eating an insect, etc.
Why do higher trophic levels have fewer organisms?
Less energy available to support them
Give an example of a long-term change in an ecosystem.
Climate change, invasive species introduction.
Give one example of a keystone species and explain why it's important.
Sea otters (control sea urchin population, protect kelp forests)
Why are food webs more realistic than food chains?
They show the many feeding relationships in an ecosystem, not just one path.
Explain the difference between competition and predation.
Competition = organisms fight for the same resource, Predation = one hunts and kills the other.
If there are 1,000 plants, 100 grasshoppers, and 10 frogs, how many hawks might there be?
Around 1
How could removing a top predator affect the whole ecosystem?
Prey populations rise, overgrazing occurs, other species decline
Describe what might happen if producers disappeared from Earth.
Collapse of food chains; no energy source for consumers.