From my reading, I learned that cellular respiration is a multi-step metabolic reaction type process that takes place in the cell of every living organism rather than plant or animal. My understanding is that there are two types of cellular respiration, one called aerobic cellular respiration which requires oxygen and anaerobic cellular respiration which does not require oxygen. In the process of anaerobic cellular respiration, unlike the aerobic process, oxygen is not needed nor is it the last electron acceptor by producing fewer ATP molecules and releasing by-products of alcohol or lactic acid. The process of anaerobic cellular respiration begins in exactly the same way as anaerobic respiration, but stops halfway due to lack of oxygen. TutorVista.com (2015) states that: “Photosynthesis and cellular respiration are metabolic reactions that complement each other in the environment. These are the same reactions but occur in opposite directions. In photosynthesis, carbon dioxide and water produce glucose and oxygen in respiration, glucose and oxygen produce carbon dioxide and water, a catabolic process that requires or contains molecular oxygen for the production of adenosine triphosphate. This three-step cycle of aerobic respiration occurs in the cytoplasm and in organelles called mitochondria. During this process, cells break down oxygen and glucose into its storable form called adenosine triphosphate or ATP. This cellular respiration, sometimes called an exothermic reaction, is similar to a combustion-type reaction where the cell releases energy in the form of heat, but at a much slower rate within a living cell. According to our text, Campbell Essential Biology with Physiology, (2010, p. 94), cellular respiration is defined as “the aerobic harvesting of energy from food molecules; the energy-releasing chemical breakdown of food molecules, such as glucose, and the storage of potential energy in a form that cells can use to carry out their work; involves glycolysis, the citric acid cycle, the electron transport chain, and chemiosmosis.” I also believe it is possible for cellular respiration to take place without oxygen, which is called anaerobic respiration. In the process of anaerobic respiration, the glycosis stage or sometimes called metabolic pathway process is delayed because the anaerobic condition produces