At  the  cell level, energy from
   sunlight   is   stored  in  organic  molecules  by  photosynthesis  in
   chloroplasts.
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   A byproduct of this process is oxygen.
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   The  organic  molecules and oxygen are used by mitochondria to produce
   ATP in a process called cellular respiration.
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   Byproducts of respiration are water and carbon dioxide, which are used
   as inputs for photosynthesis.
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   Heat is released into the environment in this cycle.
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   Exercise:  <A ClAsS=ACT Href="http://media.pearsoncmg.com/bc/bc_campbell_biology_7/media/activities/load.html?9&amp;A" oNClick="popact('http://media.pearsoncmg.com/bc/bc_campbell_biology_7/media/activities/load.html?9&amp;A');txtcolor('energy_cycling1','gray');return false;" Id=energy_cycling1><iMg sRc="/images/tutorial.gif" aLt='' boRDer=0></A>
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