Answer:
Water, carbon, and nitrogen
Step-by-step explanation:
There are numerous cycles of matter in the natural world, but three of them play very significant roles in ecosystems: the water cycle, the carbon cycle, and the nitrogen cycle.
Each cycle serves its own purpose. The water cycle is the process by which water falls to the earth's surface, is used up by humans and other living organisms, and is brought back up into the air by evaporation/transpiration. The carbon cycle is the process by which carbon is produced by factories and/or living organisms and then used up in other systems that help organisms survive. And, finally, the nitrogen cycle is the process by which nitrogen circulates throughout the ecosystem, from the atmosphere to nitrogen-fixing bacteria in the soil to plants and organisms and back into the atmosphere.
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