| A | B |
|---|
| ecology | scientific study of interactions among organisms and between organisms and their enviroments |
| biosphere | combined portions of the planet where life exists. |
| species | group of organisms so familiar to one another that they can breed and produce fertile offspring |
| population | groups of individuals that belong to the same species and live in the same area |
| community | assemblages of different popuations that live together in a defined area |
| ecosystem | living and nonliving things that live together in a particular place |
| biome | group of ecosystems |
| autotroph | organisms that attain energy from sunlight or chemicals |
| producer | organisms that make their own food |
| photosynthesis | a process responsible for adding oxygen and removing carbon dioxide |
| chemosynthesis | when organisms use chemical energy to produce carbohydrates |
| heterotroph | organisms that rely on other organisms for their energy and food supply |
| consumer | kind of heterotroph |
| herbivore | obtain energy by eating only plants |
| carnivore | eat just animals |
| omnivore | eat plants and animals |
| detritivore | feed on plant and animal remains |
| decomposer | breaks down organic matter |
| food web | links all the food chains in an ecosystems together |
| food chain | a series of steps in which organisms transfer energy by eating and being eaten |
| trophic level | each stepin a food chain or food web |
| ecological pyramid | diagram that shows the relative amounts of energy or matter contained within each trophic level |
| biomass | the total amount of living tissue within the given trophic level |
