The Carbon and Oxygen Cycles

• The carbon and oxygen cycles are independent but very closely related. 

• The cycling of Carbon and oxygen in an ecosystem results from photosynthesis and cellular respiration.
• Carbon dioxide is also released when fossil fuels are burned and when decomposers break down the tissue of organisms.

Summary of the cycles

Carbon dioxide (CO₂) is taken in by plants to be used in the process of photosynthesis.  During photosynthesis carbon based compounds are produced from this CO₂ and the water (H₂O) that  is absorbed by the roots of the plant.  Plants give off oxygen (O₂) as a waste product of photosynthesis.

 When animals consume plants or other animals they take in the carbon based compounds.   Animals inhale the O₂ given off by plants and exhale CO_2, a waste product of cellular respiration.   

Plants also take in CO₂ and release O₂ during the process of cellular respiration.

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