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Biology
Term | Definition |
---|---|
Autotroph | organism that captures energy from the sun or chemicals and use it to produce its own food |
primary producer | first producer of energy-rich compounds that are later used by other organism |
photosynthesis | process used by plants to make food from sunlight |
chemosynthesis | process in which chemical energy is used to produce carbohydrates |
heterotroph | organism that obtains food by consuming other living things |
consumer | organism that relies on other organisms for its food and energy |
carnivore | organism that obtains energy by eating animals |
herbivore | organism that obtains energy by eating only plants |
scavenger | animal that consumes carcasses of other animals |
omnivore | organism that obtains energy by eating both plants and animals |
decomposer | organism that breaks down and obtains energy from dead organic matter |
detritivore | organism that feeds on plant and animal remains and other dead matter |
food-chain | series of steps in a ecosystem in which organisms transfer energy by eating and being eaten |
phytoplankton | photosynthetic algae found near the surface of the ocean |
food web | network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem |
zooplankton | small free floating animals that form part of plankton |
trophic level | each level in a food chain or food web |
ecological pyramid | illustration of the relative amounts of energy or matter contained within each trophic level in a given chain or food web |
biomass | total amount of living tissue within a given trophic level |
biogechemical cycle | process in which elements, compounds, and other forms of matter are passed from organism to another |
nutrient | chemical substance that an organism needs to sustain life |
nitrogen fixation | process of converting nitrogen gas into nitrogen compounds that plants can absorb and use |
denitrification | process by which bacteria convert nitrates into nitrogen gas |
limiting nutrient | single essential nutrient that limits productivity in an ecosystem |