The death of a cell.
This picture is an amazing 3D illustration of apoptosis. The word “apoptosis” originates from Ancient Greek ἀπό, “away from” and πτῶσις, “falling” and it is a regulated process of cell death.
There are two ways of cell death: necrosis and apoptosis. Necrosis is a form of traumatic cell death that results from acute cellular injury, and it usually causes inflammation, because of cell’s content released outside in the extracellular fluid. Apoptosis, on the other hand, could confer advantages during an organism’s lifecycle and it produces cell fragments called apoptotic bodies that phagocytic cells are able to engulf and quickly remove, before the cell’s content spills out onto surrounding cells, causing damage.
A cell initiates intracellular apoptotic signaling in response to a stress, which may bring about cell suicide. The binding of nuclear receptors by glucocorticoids, heat, radiation, nutrient deprivation, viral infection, hypoxia and increased intracellular calcium concentration, for example, by damage to the membrane, can all trigger the release of intracellular apoptotic signals by a damaged cell.
Research in and around apoptosis has increased substantially since the early 1990s. In addition to its importance as a biological phenomenon, defective apoptotic processes have been implicated in an extensive variety of diseases. Excessive apoptosis causes atrophy, whereas an insufficient amount results in uncontrolled cell proliferation, such as cancer.