The organelle known as the "powerhouse of the cell" is the mitochondrion. Mitochondria are essential for energy production in cells as they are responsible for converting nutrients into adenosine triphosphate (ATP), the energy currency of the cell, through a process called cellular respiration. This function is crucial for maintaining cellular activities and overall function of the organism. The ability of mitochondria to generate ATP is mainly due to their unique inner membrane structure, which hosts the electron transport chain and ATP synthase enzyme.