A) By breaking down the remains of dead organisms.
B) By going to the grocery store and shopping for food.
C) By making their own food from the sun.

A) The amount of energy is highest at the top of the pyramid.
B) The amount of energy is highest in the middle of the pyramid.
C) The amount of energy is highest at the bottom of the pyramid.

A) The way that animals mate with one another.
B) A term scientists use that shows that organisms are getting along in an environment.
C) The struggle among organisms to survive in a habitat with limited resources.

A) Mutualism
B) Parasitism
C) Commensalism

A) An apple growing from a tree.
B) Fungus on a beetle bug.
C) Feathers on a bird fluffing up in the wind.

A) Harmed
B) Helped

A) Never
B) Slowly
C) Rapidly

A) Zebras eat tall grass and wildebeests eat short grass
B) Wildebeests don't eat grass so the zebras can have it all
C) Zebras don't eat grass so the wildebeests can have it all

A) Rabbit is predator
B) Owl is predator

A) Because the parasite depends on its host for its needs.
B) It wouldn't be a bad a idea for a parasite to kill its host.
C) Because the parasite should probably die on its own.

A) No one would touch them
B) Everyone getting along
C) Comparison
D) Competition