Final answer:
Oxygen is produced as a byproduct of photosynthesis and consumed as a reactant in cellular respiration. These two processes are connected in the carbon cycle, recycling oxygen and carbon dioxide in Earth's atmosphere.
Step-by-step explanation:
The role of oxygen in photosynthesis and cellular respiration is reciprocal. During photosynthesis, oxygen is produced as a byproduct when water molecules are split to provide electrons. This process consumes carbon dioxide and releases oxygen. On the other hand, during cellular respiration, oxygen is a reactant that works alongside glucose to produce ATP, which is the main energy currency in cells. As a result, carbon dioxide and water are generated as waste products.
Photosynthesis and cellular respiration are intimately connected in the biological carbon cycle. The oxygen released during photosynthesis is the same oxygen that is consumed during cellular respiration. This relationship sustains life on Earth by recycling oxygen and carbon dioxide in the atmosphere. Oxygen also enables cellular respiration to occur efficiently, allowing organisms to produce the ATP necessary for cellular functions.