AP BIOLOGY

Detailed explanation-1: -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-2: -Cells that die as a result of acute injury typically swell and burst. They spill their contents all over their neighbors-a process called cell necrosis-causing a potentially damaging inflammatory response. By contrast, a cell that undergoes apoptosis dies neatly, without damaging its neighbors.

Detailed explanation-3: -B. Apoptosis triggered by external signals. caspase 8 (like caspase 9) initiates a cascade of caspase activation leading to the death of the cell.

Detailed explanation-4: -Apoptosis is a process. And this is true, too. Apoptosis allows cells to be marked for death and thus the cell can get rid of it.