Final answer:
Mitochondria undergo cellular respiration to produce adenosine triphosphate (ATP), which is the main energy-carrying molecule that provides energy for cellular functions.
Step-by-step explanation:
The mitochondrion undergoes a process known as cellular respiration to provide energy for the cells. This essential function involves the conversion of nutrients into adenosine triphosphate (ATP), which is the primary energy-carrying molecule within the cell. Mitochondria use the chemical energy found in glucose and other nutrients to create ATP in a series of reactions that require oxygen and release carbon dioxide as a byproduct.