What is the primary function of mitochondria in eukaryotic cells?

The primary function of mitochondria in eukaryotic cells is energy production. Mitochondria are often referred to as the "powerhouses" of the cell because they are the sites where cellular respiration occurs. During this process, mitochondria convert nutrients from food into adenosine triphosphate (ATP), which is the main energy currency of the cell.

Through oxidative phosphorylation, mitochondria utilize oxygen to help break down glucose and fatty acids, ultimately producing ATP along with carbon dioxide and water as byproducts. This energy is essential for various cellular activities, allowing cells to perform functions such as muscle contractions, nerve impulse propagation, and biosynthesis of macromolecules.

While proteins are synthesized by ribosomes, DNA replication occurs in the nucleus, and cell division involves the cytoskeleton and other structures, none of these processes are the direct functions of mitochondria. Thus, the emphasis on energy production highlights the significance of mitochondria in maintaining the cell's energy balance and supporting life processes.