•Study of the interactions between organisms and their environment

•Living things in the environment

•Nonliving things in the environment

•Living and nonliving things in an area

•Part of the Earth that holds living things

Organisms that make their own food

•Organisms that get food from an outside source

•Consumers that eat plants

Consumers that eat meat

Consumers that eat plants and meat

•Consumers that eat dead organisms

•Organisms that break down dead organisms

•A complex diagram showing many energy pathways in an ecosystem

Triangular diagram showing the loss of energy at each level of the food chain

•Resources that are scarce

•Organisms that eat other organisms

•Organisms that are eaten by other organisms

Long term changes that take place because two species are in close association with each other