The main role of oxygen in photosynthesis and respiration is that Oxygen is released in photosynthesis and used in cellular respiration to produce energy.
In photosynthesis, water and carbon dioxide reacts to form oxygen and glucose while on the other hand, In cellular respiration, oxygen is used to break down glucose in order to release energy in the form of ATP.
So we can conclude that the main role of oxygen in photosynthesis and respiration is that Oxygen is released in photosynthesis and used in cellular respiration to produce energy.
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