Mitochondria play a crucial role in cellular metabolism by generating adenosine triphosphate (ATP), the primary energy currency of the cell. They convert energy stored in nutrients into ATP through processes such as oxidative phosphorylation and the Krebs cycle. Mitochondria also regulate metabolic pathways and participate in the apoptosis process, thereby influencing energy balance and cell fate. By producing reactive oxygen species (ROS), they also play a role in intracellular signaling. Dysfunction in mitochondria can lead to a variety of metabolic diseases and conditions due to impaired energy production.