Photosynthesis and cellular respiration are interconnected processes that sustain life on Earth. During photosynthesis, plants convert sunlight, carbon dioxide, and water into glucose and oxygen, using chlorophyll. The glucose produced serves as a primary energy source. In contrast, cellular respiration involves the breakdown of glucose in the presence of oxygen to release energy stored in the form of ATP, producing carbon dioxide and water as byproducts. Essentially, the oxygen produced in photosynthesis is used in cellular respiration, while the carbon dioxide generated in respiration is utilized in photosynthesis, creating a cyclic relationship.