Feature of Apoptosis
High-Yield Explanation
Features of Necrosis and ApoptosisFeatureNecrosisApoptosisCell sizeEnlarged (swelling)Reduced (shrinkage)NucleusPyknosis - karyorrhexis - karyolysisFragmentation into nucleosome-sizefragmentsPlasmamembraneDisruptedIntact; altered structure,especially orientation of lipidsCellularcontentsEnzymatic digestion;may leak out of the cellIntact; may be released inapoptotic bodiesAdjacentinflammationFrequentNoPhysiologic orpathologicroleInvariably pathologic(culmination ofirreversible cellinjury)Often physiologic, means ofeliminating unwanted cells;may be pathologic after someforms of cell injury, especiallyDNA damageRef: Robbins and Cotran Pathologic Basis of Disease; 9th edition; Chapter 2; Cellular Responses to Stress and Toxic Insults: Adaptation, Injury, and Death