Table 1.

The various morphological changes that occur during apoptosis have been identified using light and electron microscopy.

Light microscopy	Electron microscopy
Chiefly characterized by cell shrinkage and pyknosis Cell shrinkage - cells are smaller in size, with dense cytoplasm containing tightly packed organelles	Extensive plasma membrane blebbing followed by karyorrhexis and separation of cell fragments into apoptotic bodies (consisting of cytoplasm with tightly packed intact organelles with or without a nuclear fragment, enclosed within an intact plasma membrane)
Pyknosis - nuclear chromatin condensation	Electron-dense nuclear material characteristically aggregates peripherally under the nuclear me brane although there can also be uniformly dense nuclei
H&E staining - single cell or small clusters of cells appearing as a round or oval mass with dark eosinophilic cytoplasm and dense purple nuclear chromatin fragments	Apoptotic bodies are subsequently phagocytosed by macrophages, parenchymal cells, or neoplastic cells and degraded within phagolysosomes