all the organisms that live in an area together with the nonliving things in the environment.
a group of organisms that can mate and produce offspring that in turn can produce more offspring.
all the members of a species living in a particular area at a particular time.
all the populations sharing a specific area or region.
structure, behavior, or other trait in an organism that helps it to survive in its environment.
a close relationship between two species.
a symbiotic relationship in which both species benefit.
a type of symbiosis in which one species benefits while the other seems to be unaffected.
a type of symbiosis that occurs when an organism called a parasite feeds on the cells, tissues, or fluids of another organism call a host.
organism that supports a parasite.
use the energy of the sun to produce their own food (plants).
any organism that gets its food by eating other organisms.
organism that feed on the remains or wastes of other organisms.
eat the remains of organisms left behind by other animals.
traces the path of energy as it moves from one organism to the next in an ecosystem.
a system of several overlapping food chains.
diagram that shows the flow of energy through a food chain.
chemical process by which plants use light energy to make sugar from water and carbon dioxide.