11.6: In a Living Organism, How Do Cells Die?
Two ways: (1) Necrosis, (2)Apoptosis
Necrosis: cells and tissues are damaged by mechanical means or toxins, or are starved of oxygen
or nutrients. These cells often swell and burst, releasing their contents into the extracellular
Apoptosis: programmed series of events that result in cell death. But why does this happen?
1. The cell is no longer needed, one example is the connective tissue between web-
like hands of a fetus
2. The longer cells live, the more prone they are to genetic damage that could lead to
• Cell becomes detached from its neighbors and its chromatin is digested by enzymes that
cut the DNAinto fragments.
• The cell then forms lobes or “blebs” that break up into cell fragments
• Living cells usually ingest the remains of t