The primary function of mitochondria in cells is to generate adenosine triphosphate (ATP), which serves as the main energy currency for cellular processes. Often referred to as the "powerhouse of the cell," mitochondria convert nutrients from food into ATP through a process called cellular respiration. This energy production is essential for various physiological functions, including muscle contraction, nerve impulse propagation, and biosynthesis of macromolecules. Beyond energy production, mitochondria are involved in regulating the cell cycle, cell growth, and apoptosis (programmed cell death), highlighting their crucial role in overall cellular health.