Which of the following best describes the function of mitochondria?

Mitochondria are often referred to as the "powerhouses" of the cell because their primary function is to produce adenosine triphosphate (ATP), the energy currency of the cell. They achieve this through the processes of cellular respiration and oxidative phosphorylation, where they convert nutrients from the food we eat into usable energy. This ATP is crucial for various cellular activities that require energy, such as muscle contraction, neural activity, and biosynthetic processes.

While protein synthesis is an important cellular function, it primarily occurs in ribosomes and not within mitochondria. Cell division is managed by other cellular structures such as the centrosome and spindle fibers, while cell structure support is provided by elements of the cytoskeleton and components of the cell membrane. Therefore, the defining function of mitochondria as vital for ATP production is paramount in understanding their role within the cell.