1.) Photosynthesis and cellular respiration are often described as been chemically opposite because the product of the photosynthesis process is the reactant of the cellular respiration process and vice versa.
The reactants of cellular respiration are glucose and oxygen and these happen to be the products of photosynthesis also. During the process of photosynthesis, plants take in carbon dioxide and water in the presence of sunlight to produce glucose and oxygen. During cellular respiration, glucose is broken down in the presence of oxygen to produce carbon dioxide and water, which are the reactants of the photosynthesis process.
2.) Photosynthesis and cellular processes are related to each other, this is because, the photosynthesis process produces the glucose, which cellular respiration used to synthesis energy in the cells of living organisms. Thus, the glucose producing plants depend on the living organisms that carried out cellular respiration to produce carbon dioxide and water, which is the necessary reactants for photosynthesis process. The organisms using cellular respiration also depend on plants to produce glucose and oxygen for their use.
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