Topic # 3

• What happens to a cell upon injury?

  It may adapt or die.
• What does degeneration imply about a cell?

  It implies a sick cell or tissue.
• What does necrosis refer to?

  Death of cell, tissue, or body portion.
• What are the hallmark features of degeneration?

  • E.R. swelling
  • Blebs formation
  • Mitochondrial swelling
  • Generalized swelling
  • Dispersion of ribosomes
  • Clumping of nuclear chromatin
  • Autophagy of lysosome
  • Aggregation of intramembranous particles
  • Small densities
• What are the hallmark features of necrosis?

  • Defects in cell membrane
  • Rupture of lysosome & autolysis
  • Large densities
  • Mitochondrial swelling & rupture
  • E.R. lysis
  • Myelin bodies
  • Nuclear changes
• What are the nuclear changes associated with necrosis?

  1. Pyknosis - condensation of nucleus
  2. Karyorrhexis - fragmentation of nucleus
  3. Karyolysis - dissolution of nucleus
• What is pyknosis?

  Condensation of nucleus.
• What is karyorrhexis?

  Fragmentation of nucleus (shattering).
• What is karyolysis?

  Dissolution of nucleus.
• What is the first form of degeneration listed?

  Cell (cloudy) swelling
• What characterizes cell (cloudy) swelling?

  Accumulation of fluid in cytoplasm
• What is ballooning degeneration?

  Accumulation of fluid in epidermal cells
• How do epidermal cells appear in ballooning degeneration?

  Swollen and rounded
• What is hydrophobic degeneration also known as?

  Serous infiltration
• What happens during hydrophobic degeneration?

  Cell swelling becomes more advanced
• What is a significant risk associated with hydrophobic degeneration?

  The cell has a tendency to burst
• What is hyaline degeneration characterized by?

  Formation and accumulation of hyaline
• What does mucoid degeneration involve?

  Formation and accumulation of mucin granules
• What is fatty degeneration?

  Deposition of fat globules
• What is fibrinoid degeneration?

  Deposition resembling fibrin in tissue
• What is colloidal degeneration?

  Conversion of tissue into gel-like material
• What does Wallerian degeneration affect?

  Nerve fiber and myelin sheath
• What are the different forms of degeneration?

  1. Cell (cloudy) swelling
  2. Ballooning degeneration
  3. Hydrophobic degeneration / serous infiltration
  4. Hyaline degeneration
  5. Mucoid degeneration
  6. Fatty degeneration
  7. Fibrinoid degeneration
  8. Colloidal degeneration
  9. Wallerian degeneration
• What is coagulative necrosis characterized by?

  Cells are dead but tissue architecture intact
• How does caseation necrosis differ from coagulative necrosis?

  Caseation necrosis loses tissue architecture and appears cheesy
• What occurs during liquefactive necrosis?

  Complete dissolution of tissue occurs
• What is gangrene a product of?

  Necrosis plus bacterial putrefaction
• What type of necrosis does dry gangrene originate from?

  Coagulative necrosis
• What type of necrosis does wet gangrene originate from?

  Liquefactive necrosis
• What causes fat necrosis?

  Reaction of lipase on adipose tissue
• What is an infarct?

  Area of coagulative necrosis due to blood flow stoppage
• What is Zenker's necrosis associated with?

  Degeneration and necrosis of striated muscles