[ bī′ō-jē′ō-kĕm′ĭ-kəl ]
The flow of chemical elements and compounds between living organisms and the physical environment. Chemicals absorbed or ingested by organisms are passed through the food chain and returned to the soil, air, and water by such mechanisms as respiration, excretion, and decomposition. As an element moves through this cycle, it often forms compounds with other elements as a result of metabolic processes in living tissues and of natural reactions in the atmosphere, hydrosphere, or lithosphere. See more at carbon cycle nitrogen cycle.
Zoom Through “Spin Class” With These 10 Cycling TermsCycling no doubt courses throughout our life and culture, but so does the language of the sport and activity. So, strap on your helmets: we're going to spin through some of the zippiest terms in cycling, past and present.
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