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SBW (133-139)
Science
Term | Definition |
---|---|
food web | complex interactions formed by the feeding relationships among various organisms in an ecosystem |
energy pyramid | compares the energry levels in an ecosystem |
trophic level | each energy level in an energy pyramid |
ecosystem | organisms and their physical environment, all interacting by a flow of energy and a cycling of materials |
biodiversity | the wide variety of life of Earth |
index fossil | remains of species that existed on Earth for a short period of time; used by geologists to assign ages to rock layers |
trace fossil | Fossilized tracks and other evidence of the activity of organisms. Can tell how organisms lived. |