Cell death Flashcards
What are the 2 ways that cells can die?
Necrosis
Apoptosis
What is apoptosis? What causes it?
Programmed cell death to eliminate host cells
Development, homeostasis, defence mechanism in immune reactions, aging, eliminate damaged cells
Does apoptosis affect cell membranes or cause inflammation?
Doesn’t affect cell membranes except mitochondria
No inflammation
What are the 4 stages to apoptosis?
Cell shrinkage
Chromatin condensation
Formation of cytoplasmic blebs and apoptotic bodies
Phagocytosis of apoptotic cell
What is necrosis? What are the 2 outcomes that cause the cell to die?
Cell death due to irreversible exogenous injury
Dystrophic calcification or phagocytosis
Does necrosis affect cell membranes? Does it cause inflammation?
Affects membranes
Causes inflammation
What two concurrent processes lead to necrosis?
Enzymatic digestion of cell - autolysis (by itself) or heterolysis (by leukocytes)
Denaturing of proteins
What are the 4 types of necrosis?
Coagulative necrosis
Liquifative necrosis
Caseous necrosis
Fat necrosis
What happens in fat necrosis? What does this look like histologically?
Destruction of adipose tissue to pancreatic enzymes
Causes chalky white areas
Induces inflammation
What disease is associated with caseous necrosis?
Tuberculosis
What is the difference between necrosis and apoptosis in terms of cell size?
Necrosis = swelling/enlargement Apoptosis = shrinking
What is the difference between necrosis and apoptosis in terms of membrane altering?
Necrosis - membranes affected
Apoptosis - no membranes affected except mitochondria
What is the difference between necrosis and apoptosis in terms of inflammation?
Necrosis = inflammation Apoptosis = no inflammation
What is the difference between necrosis and apoptosis in terms of physiological/patholgoical role?
Necrosis = always pathological Apoptosis = can be pathological, but physiologically eliminates unwanted cells
