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What is a Cycle in Science? - Windows to the Universe

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Become a nitrogen atom in the nitrogen cycle in our Traveling Nitrogen Classroom Activity Kit/Game. See all our games, activity kits and classroom activities.
The seasons are a well-known example of a cycle.
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What is a Cycle?

You may have studied the water cycle or the rock cycle in school. These are just two examples of cycles.

Very simply, when scientists talk about cycles, they are talking about sequences of events that repeat themselves. Some cycles are very simple. For example, the seasons of the year represent a cycle in that they always repeat – Winter, Spring, Summer, Fall, and then back to Winter!

The nitrogen and carbon cycles are very complex cycles. They fit into the category called biogeochemical cycles.

Last modified June 29, 2005 by Jennifer Bergman.

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The Winter 2009 issue of The Earth Scientist, focuses on Earth System science, including articles on student inquiry, differentiated instruction, geomorphic concepts, the rock cycle, and much more!

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