Features

• Forming bonds among atoms to create a molecule releases energy, while breaking bonds requires energy. If the energy released by a reaction is greater than the energy it took to break bonds in the reactants, the reaction releases energy. Note that this energy has not been created -- merely converted from one form to another. Photosynthesis is the opposite of this process, as it stores energy from sunlight as chemical potential energy.
  
  

Effects

• The net chemical equation for photosynthesis looks deceptively simple: six molecules of carbon dioxide combine with six molecules of water to form one molecule of glucose and six oxygen molecules. The actual process involves many other steps, of course, but the most important point is that the glucose molecule has higher potential energy than the reactants: The reaction has stored energy from light as energy in chemical bonds.
  
  

Function

• In photosynthesis, molecules of pigments like chlorophyll absorb photons of light; excited electrons then transfer this energy, powering a process that will ultimately drive the synthesis of a compound called adenosine triphosphate or ATP. This ATP is in turn used to drive the synthesis of sugars through a chain of reactions called the Calvin cycle.