The released Oxygen in the process of photosynthesis is utilised by the living organism to undergo the process of respiration.In respiration the Oxygen from the environment is inhaled by the living organism and which is carried to the cell and perform cellular respiration.In living organism, the Oxygen is used for breaking down the biochemical energy and convert them into ATP which is utilised by the body to perform work.
Importance:
Photosynthesis is the process utilized in the chloroplasts of plant cells, where carbon dioxide and water undergo a chemical process with radiant energy, usually from the sun. The products produced are glucose molecule, and oxygen, which is given off as a waste product. Now, the oxygen given off in this process is one of the essential requirement which each process require to begin.
Animal cells use cellular respiration, where a glucose molecule is oxidized by an oxygen molecule. The resulting products are energy in the form of ATP (adenosine triphosphate) and carbon dioxide and water, which are waste products and are then required by the plants to carry out the process of photosynthesis.
Thus, it could be seen that cellular respiration and photosynthesis represent a cyclical processing of oxygen.
Also, it is important for maintaining oxygen balance in atmosphere​.
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