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Vocab 18.4

Terms for chapter 18 section 4

biogeochemical cycle the circulation of substances through living organisms from or to the environment
groundwater the water that is beneath the Earth's surface
water cycle the continuous movement of water between the atmosphere, the land, and the oceans
transpiration the process by which plants release water vapor into the air through stomata; also the release of water vapor into the air by other organisms
carbon cycle the movement of carbon from the nonliving environment to the living things and back
nitrogen cycle the process in which nitrogen circulates among the air, soil, water, plants, and animals in an ecosystem
nitrogen fixation the process by which gaseous nitrogen is converted into nitrates, compounds that organisms can use to make amino acids and other nitrogen-containing organic molecules
nitrogen-fixing bacteria a bacteria that converts atmospheric nitrogen into ammonia
ammonification the formation of ammonia compounds in the soil by the action of bacteria on decaying matter
nitrification the process by which nitrites and nitrates are produced by bacteria in the soil
denitrification the liberation nitrogen from nitrogen-conatining compounds by bacteria in the soil
phosphorus cycle the cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment
Created by: SheaM16