Apoptosis

Apoptosis is a mechanism of cell death that occurs after sufficient cellular damage. It occurs normally during development and aging and is considered a vital component of cell turnover, cell development and function of the immune system. It occurs as a defense mechanism such as in immune reactions or when cells are damaged by disease or noxious agents.Apoptosis, in general, confers advantages during an organism's life cycle. Between 50 billion and 70 billion cells die each day due to apoptosis in the average human adult. In a year, this amounts to the proliferation and subsequent destruction of a mass of cells equal to an individual's body weight. Inappropriate apoptosis is a factor in many human conditions including neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer. The ability to modulate the life or death of a cell is recognized for its profound therapeutic potential, and research continues to focus on the elucidation of the cell cycle machinery and signaling pathways that control cell cycle arrest and apoptosis.