2.2 & 2.3

the total mass of organisms in a given area or volume.

an animal that feeds on flesh.

an animal that feeds on dead organic material, especially plant detritus.

a hierarchical series of organisms each dependent on the next as a source of food.

a system of interlocking and interdependent food chains.

an animal that feeds on plants.

an animal or person that eats food of both plant and animal origin.

an organism deriving its nutritional requirements from complex organic substances.

each of several hierarchical levels in an ecosystem, comprising organisms that share the same function in the food chain and the same nutrit

substance turnover is a pathway by which a chemical substance moves through both the biotic (biosphere) and abiotic (lithosphere, atmosphere

the loss or removal of nitrogen or nitrogen compounds; specifically :reduction of nitrates or nitrites commonly by bacteria (as in soil) tha

physical substance in general, as distinct from mind and spirit; (in physics) that which occupies space and possesses rest mass, especially

the chemical processes by which atmospheric nitrogen is assimilated into organic compounds, especially by certain microorganisms as part of

a substance that provides nourishment essential for growth and the maintenance of life.