Respiration occurs in the mitochondria of a cell. These organelles are often referred to as the "powerhouses" of the cell because they are responsible for producing adenosine triphosphate (ATP), which serves as the primary energy currency for cellular functions. During respiration, cells convert glucose and oxygen into energy, carbon dioxide, and water through a series of biochemical processes, namely glycolysis, the Krebs cycle, and oxidative phosphorylation. This energy production is vital for maintaining cellular activities, supporting growth, and enabling movement. Mitochondria also play a role in regulating metabolism and various signaling pathways within the cell.