Organisms that produce their own food mostly through photosynthesis (producers). Examples are plants and algae.

Heterotrophs that get energy and nutrition from dead or decaying organisms or their waste products and recycle nutrients back to the ecosystem.

Heterotrophs that “clean up” the ecosystem by eating dead and decaying organisms.

The level in an Ecological pyramid that includes all the organisms that share the same place in a food chain.

Autotrophs--The bottom trophic level where all organisms produce their own food, usually by photosynthesis.

Herbivores--The second trophic level where herbivores eat the primary producers.

The third trophic level where the animals eat herbivores.

The fourth trophic level where animals eat secondary consumers or below.

Only 10% of the energy is passed on from one trophic level to the next. 90% is lost as heat due to cellular respiration or waste.

Matter is passed up the ecological pyramid in a similar way to energy but recycled by decomposers and detritivores. This Biomass pyramid roughly follows the 10% rule as well.

Complex trophic relationships in an ecological pyramid.

Parts of an ecosystem that are living or deal with the living. Examples include producers, consumers, decomposers, predation, disease, competition, parasitism, and symbiosis.

One organism consuming another organism.

Parts of an ecosystem that are not living. Examples: water, soil, sunlight, temperature, altitude.

The flow of nitrogen from the atmosphere to the soil, to plants, to animals and then back to the soil or back into the atmosphere.

The flow of carbon from the atmosphere to plants, to animals to the soil and back into the atmosphere.