Which term describes programmed cell death used to remove damaged or unnecessary cells?

Which term describes programmed cell death used to remove damaged or unnecessary cells?

• A. Apoptosis
• B. Necrosis
• C. Mitosis
• D. Fermentation

Answer: (A)

Programmed cell death, or apoptosis, is a controlled process that eliminates cells that are damaged or no longer needed. It’s energy-dependent and involves a cascade of enzymes called caspases that lead to orderly changes: the cell shrinks, DNA is fragmented, the nucleus condenses, and the cell’s membrane forms blebs and fragments into small apoptotic bodies that are quietly cleared by phagocytes. This prevents inflammation and helps shape tissues during development, remove self-reactive immune cells, and maintain cellular balance. In contrast, necrosis is accidental cell death caused by injury, leading to cell swelling, rupture, and inflammation. Mitosis is cell division, not death, and fermentation is a metabolic process to generate energy under low-oxygen conditions, not a mechanism for removing cells.

Programmed cell death, or apoptosis, is a controlled process that eliminates cells that are damaged or no longer needed. It’s energy-dependent and involves a cascade of enzymes called caspases that lead to orderly changes: the cell shrinks, DNA is fragmented, the nucleus condenses, and the cell’s membrane forms blebs and fragments into small apoptotic bodies that are quietly cleared by phagocytes. This prevents inflammation and helps shape tissues during development, remove self-reactive immune cells, and maintain cellular balance.

In contrast, necrosis is accidental cell death caused by injury, leading to cell swelling, rupture, and inflammation. Mitosis is cell division, not death, and fermentation is a metabolic process to generate energy under low-oxygen conditions, not a mechanism for removing cells.