AP BIOLOGY

Detailed explanation-1: -Apoptosis is a form of programmed cell death, or “cellular suicide.” It is different from necrosis, in which cells die due to injury. Apoptosis is not the only form of programmed cell death, but it is the form we understand best.

Detailed explanation-2: -Following the induction of DNA damage, a prominent route of cell inactivation is apoptosis. During the last ten years, specific DNA lesions that trigger apoptosis have been identified. These include O6-methylguanine, base N-alkylations, bulky DNA adducts, DNA cross-links and DNA double-strand breaks (DSBs).

Detailed explanation-3: -Apoptosis occurs normally during development and aging and as a homeostatic mechanism to maintain cell populations in tissues. Apoptosis also occurs as a defense mechanism such as in immune reactions or when cells are damaged by disease or noxious agents (Norbury and Hickson, 2001).

Detailed explanation-4: -Apoptosis is the process of programmed cell death. It is used during early development to eliminate unwanted cells; for example, those between the fingers of a developing hand. In adults, apoptosis is used to rid the body of cells that have been damaged beyond repair. Apoptosis also plays a role in preventing cancer.

Detailed explanation-5: -During apoptosis, the cell shrinks and pulls away from its neighbors. Then the surface of the cell appears to boil, with fragments breaking away and escaping like bubbles from a pot of hot water. The DNA in the cell’s nucleus condenses and breaks into evenly sized fragments.