a person or thing that eats or uses something

an organism, especially a soil bacterium, fungus, or invertebrate, that decomposes organic material.

bacteria change nitrate (protein) to nitrogen gas

factors whose effects on the size or growth of the population vary with the population density. Example: availability of food, predation, disease

factors whose effects on the size or growth of the population is not affected by the population density. Example: Hurricanes, earthquakes

the branch of biology that deals with the relations of organisms to one another and to their physical surroundings.

the surroundings or conditions in which a person, animal, or plant lives or operates

environmental conditions that limit the growth, abundance, or distribution of an organism or a population of organisms in an ecosystem

symbiosis that is beneficial to both organisms involved

the chemical processes by which nitrogen gas is changed into organic compounds, especially by certain bacteria as part of the nitrogen cycle.

symbiotic relationship between two species of plants or animals in which one benefits, and the other is harmed, sometimes to the point of killing the host organism

species which are the first to colonize damaged ecosystems after disasters such as fires and volcanic eruptions.

a particular group, or type of plants and/or animals living in a given area

an animal that lives by killing and eating other animals: an animal that preys on other animals

a situation in which two or more organisms or groups are trying to get something which not everyone can have.

a source of supply, support, or aid, especially one that can be readily drawn upon when needed. i.e. food, water, shelter

an animal that is hunted and killed by another for food.

occurs in essentially lifeless areas—regions in which the soil is incapable of sustaining life as a result of such factors as lava flows, newly formed sand dunes, or rocks left from a retreating glacier.

An autotrophic organism that serves as a source of food for other organisms in a food chain. Includes green plants, which produce food through photosynthesis, and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis.

A process started by an event (e.g. forest fire, harvesting, hurricane, etc.) that reduces an already established ecosystem (e.g. a forest or a wheat field) to a smaller population of species; occurs on preexisting soil

two or more dissimilar organisms living on or inside of each other

the sequence of transfers of matter and energy in the form of food from organism to organism.

two or more food chains woven together

When organisms eat other organisms, energy is transferred. This can be used to diagram this flow of metabolic energy

The amount of organic matter that can be found in any living organism is called biomass. This is a graph of the total amount of biomass found in each ecosystem

The amount of heat transfered from each trophic level to the next shown in a food chain, food pyramid or energy pyramid is only 10%

A term that is used for each level on a pyramid or step in a food chain or web.