Cellular respiration is the set of chemical reactions that break down glucose from our food into ATP or andesine triphosphate. The ATP is energy for the body. Cellular respiration requires Oxygen and glucose to start the cycle. Cellular respiration takes place in the mitochondria or “powerhouse” of the cells. They take in the Oxygen and glucose and turn it into Carbon dioxide, water, and ATP. The Carbon dioxide and the water are the byproducts of the reactions. This is what cellular respiration is!