Photosynthesis and cellular respiration play significant roles in existence of all living organisms on the planet. Supplying energy to the cells they carry out is the main process called life. Photosynthesis is the process by which several living organisms such as plants and bacteria utilize sunlight and several raw materials such as carbon dioxide and water to produce sugars and release oxygen into the atmosphere. It does not only supplies oxygen which required for human life but it is also the primary source of food energy for all forms of life, directly or indirectly. Cellular respiration is the process of converting food molecules such as glucose into energy in the form of ATP. In this process, oxygen is utilized and carbon dioxide is produced. Carbon dioxide, required for photosynthesis by plants is replenished by carbon dioxide released in respiration. Similar to oxygen required for respiration is replenished by oxygen released in photosynthesis. Thus, photosynthesis and cellular respiration compliments each other to help maintaining the balance of oxygen and carbon dioxide in nature. Three differences that exist between these two chemical processes is that photosynthesis captures sunlight energy to make food for the plants and other organisms while cellular respiration extracts energy from food molecules. Another difference between photosynthesis and respiration is where it occurs, one being in plants and some bacteria and the other being in most every other living thing. The last difference is cellular respiration processes are divided into processes that require oxygen and those that do not require oxygen while the processes of photosynthesis are divided into those that require light energy and those that do not require light energy. The things to remember are that photosynthesis uses carbon dioxide, water and light to make glucose and oxygen, while respiration uses glucose and oxygen to make carbon dioxide, water and ATP.