Term | Definition |
Autotroph | Organism that is able to capture energy from sunlight or chemicals and use it to produce it's own food from inorganic compounds; also called a producer |
Primary Producer | First producer of energy-rich compounds that are later used by other organisms. |
Photosynthesis | Process used by plants and other autotrophs to capture light energy and use it to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates such as sugars and starches. |
Chemosynthesis | Process in which chemical energy is used to produce carbohydrates. |
Heterotroph | Organism that obtains food by consuming other living things; also called a consumer. |
Consumer | Organism that relies on other organisms for it's energy and food supply; also called a heterotroph |
Carnivore | Organism that obtains energy by eating animals. |
Herbivore | Organism that obtains energy by eating only plants. |
Scavenger | Animal that consumes the 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 plants and animal remains and other dead matter. |
Food Chain | Series of steps in an 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. |
Tropical Level | Each step 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 food chain or food web. |
Biomass | Total amount of living tissue within a given trophic level. |
Biogeochemical Cycle | Process in which elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere 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 in which bacteria converts nitrates into nitrogen gas. |
Limiting Nutrient | Single essential nutrient that limits productivity in an ecosystem. |