Photosynthesis is the process in which light energy of the sun is converted to chemical energy. The process also consumes carbon dioxide from the atmosphere and we end up with glucose and oxygen. It is this process which makes plants so special as the chief source of food and oxygen on Earth. The oxygen so released is used in the respiration process to break down complex molecules (generated in photosynthesis) and releases energy in the form of ATP (adenosine triphosphate) molecules. This energy is used in anabolism and for maintenance activities. Without oxygen generated from photosynthesis, respiration is not possible. Without respiration, plants will not grow and will be incapable of photosynthesis. Thus, respiration and photosynthesis are interlinked and feed reactants to each other.
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