Photosynthesis involves the use of energy from sunlight, water and carbon dioxide to produce glucose and oxygen. Cellular respiration uses glucose and oxygen to produce carbon dioxide and water. ... For example, both processes synthesize and use ATP, the energy currency.
2.) Seawater has many different gases dissolved in it, especially nitrogen, oxygen and carbon dioxide. It exchanges these gases with the atmosphere to keep a balance between the ocean and the atmosphere. This exchange is helped by the mixing of the surface by wind and waves. :)))