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How are mitochondria involved in cell growth and programmed cell death?

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Fluorescent confocal image of HeLa cells with green microtubules outlining cell shapes, red mitochondria, and blue nuclei. — mitochondrion Mitochondria (red) are found throughout the cytoplasm of almost all eukaryotic cells (cell nucleus is shown in blue; cytoskeleton is shown in yellow).

Mitochondria are essential organelles that play a critical role in both cell growth and programmed cell death, a process known as apoptosis.12

Role in Cell Growth

Mitochondria are often called the "powerhouses of the cell" because they generate the adenosine triphosphate (ATP) required to fuel cellular activities, including growth and development. By breaking down nutrients through aerobic metabolism, mitochondria provide the energy necessary for protein synthesis and other processes that allow cells to function and proliferate. Additionally, they store calcium, which acts as a vital signaling molecule for various cellular activities.123

Role in Programmed Cell Death

Mitochondria are central components of apoptosis, the process by which the body removes cells that are no longer useful or are functioning improperly. While mitochondria remain preserved until late in the apoptotic process, they are key mediators of this "programmed" death. Because they are so integral to this regulatory mechanism, mitochondrial dysfunction that prevents apoptosis can contribute to the development of cancer, as cells that should be eliminated instead continue to survive and divide.24