The structure in the cell responsible for energy production is the mitochondrion, often referred to as the "powerhouse" of the cell. Mitochondria convert nutrients into adenosine triphosphate (ATP), which is the primary energy currency of the cell. This process occurs through cellular respiration, which involves a series of biochemical reactions that break down glucose in the presence of oxygen. The efficiency of mitochondria is crucial for various cellular functions, as they provide the energy needed for growth, maintenance, and repair. Additionally, mitochondria have their own DNA, supporting their role in energy metabolism and cellular health.