chapter 3: cellular adaptation, injury, and death Flashcards
what are the different types of ADAPTIVE STRESS?
- atrophy
- hypertrophy
- hyperplasia
- metaplasia
- dysplasia
what is atrophy?
cell size: decrease
tissue mass: decrease
what is hypertrophy?
individual cell size: increase
tissue mass: enlarged
what is hyperplasia?
cell number: increase
tissue mass: enlarged
what is metaplasia?
mature cell type is replaced by DIFFERENT cell type
what is dysplasia?
cells: shape + size vary
nuclei: large
mitosis rate: increased
what is intracellular accumulation?
buildup of substances that cells CANNOT use or eliminate
what causes intracellular accumulation of substances?
- normal body substances
- abnormal endogenous products
- abnormal exogenous products
what are normal body substances?
synthesized rate EXCEEDS metabolism or removal
e.g. lipids, proteins, pigments (melanin, bilirubin)
results: fatty liver disease, jaundice, lipofuscin
what are abnormal endogenous products?
produced by INBORN ERRORS of metabolism (missing an important enzyme)
e.g. metabolic products (affects glycogen lipids metabolism)
results: tay sach’s disease
what are abnormal exogenous products?
ENVIRONMENTAL agents + PIGMENTS that CANNOT be broken down by cell
e.g. carbon (as coal dust), lead poisoning, tattoos
what is meant by abnormal endogenous/exogenous accumulation of intracellular substances?
abnormal endogenous: produced by abnormal synthesis/metabolism
abnormal exogenous: produced by environmental agents that cannot be broken down by the cell
what are the characteristics of dystrophic calcification?
- normal calcium levels
- microscopic deposits of calcium salts in injured tissue
- deposits come from DEAD/DYING cells
leads to: advanced atherosclerosis, damaged heart valves, tb lesions
what are the characteristics of metastatic calcification?
- location: normal tissue
- cause: increased serum calcium levels (lung, kidney, bv’s –> abnormality in calcium metabolism)
- hyperparathyroidism [in renal failure], bone destruction
leads to: immobilized patients, paget disease, cancer w/metastatic bone lesions
what causes cells to die?
damaging factor to cell is NOT removed
leads to: morphological changes > death
how does hypoxia cause cell death?
aerobic metabolism stops > less ATP produces
- Na+/K+ ATPase DECREASES > INCREASE intracellular Na+ > cells SWELL w/ water
anaerobic metabolism used > produces lactic acid
- acid damages cell membranes, intracellular structures, dna
what is apoptosis?
programmed cell death
e.g. webbed fingers, stripping of inner lining of uterus during menstruation
what is necrosis?
localized tissue death in organ/tissue (response to disease/injury)
e.g. gangrenous necrosis
what are the types of necrosis?
liquefaction
coagulative
caseous
what is liquefaction necrosis?
brain tissue dies, bacterial infection (leaves a whole)
what is coagulative necrosis?
hypoxic injury leading to infractions > mi (i.e dead tissue replaced w/CT)
what is caseous necrosis?
dead cell persists as a soft, cheese-like debris > tb
what is gangrene?
when a considerable mass of tissue undergoes necrosis (coagulative necrosis develops in ischemic tissue)
what is dry gangrene?
arterial blood supply: no
venous flow: yes (carries fluid out of tissue)
how do you identify dry gangrene?
- dry, shrinks, skin wrinkles, dark brown/black
- clear line of demarcation
- spreads slowly
- confined to extremeties
what is wet gangrene?
arterial blood supply: yes (fluid in tissue)
venous flow: no
how do you identify wet gangrene?
- cold, swollen, pulseless, moist, black
- FOUL ODOR FROM BACTERIA
- liquefaction
- no line of demarcation
- spreads rapidly
- affects internal organs or extremeties
what is gas gangrene?
bacterial infection, produces GAS in tissue; DEADLY
how do you identify gas gangrene?
- muscle cell death
- massive spreading edema
- rbc hemolysis
- hemolytic anemia
- hemoglobinemia
- renal failure
