a product of the environment that is used by humans or other organisms

a measure of the ability of a substance to allow an electric current pass through it

the amount of water vapor in the air

a material that does not allow electric current or heat to pass through it easily

something in an ecosystem that keeps a population from getting too large

a symbiotic relationship in which both species benefit from the interaction

pollution that comes from a single identifiable site

a material that does not allow electric current or heat to pass through it easily

a push or pull that acts on an object

all the organisms in an area as well as their relationships with each other and the abiotic materials in the environment

the amount of mass in every given volume of matter