The two main processes by which plant cells absorb, release, and use energy are photosynthesis and respiration. The process of photosynthesis is present in the chloroplasts of a pant cell. Photosynthesis uses the sun’s rays in the form of electromagnetic energy to convert it into chemical energy to be used for the plants. It needs proteins that are present in the plants to perform a series of necessary conversions. Moreover, the energy from the sun is the main catalyst to convert the carbohydrates in the plant into simpler sugars. And then a series of complex reaction takes place that their end product is oxygen. The oxygen produced is the cellular respiration.