Answer:
Cellular respiration
Step-by-step explanation:
Cellular (aerobic) respiration is a process by which both autotrophic and heterotrophic organisms obtain energy by conversing adenosine diphosphate (ADP) to adenosine triphosphate (ATP). During this process, oxygen (O2) is combined with molecules obtained from the food, thereby releasing carbon dioxide (CO2) and water (H2O). Cellular respiration has three steps: glycolysis, the Krebs cycle, and the chain of electron transport: the first step (glycolysis) is carried out in the cytosol, while the last two take place in the mitochondria.