necrosis and cell damage

Question 1

causes of cell injury

Answer 1

chemical 
physcial 
infective 
hypoxia 
immune

Question 2

responses to cell injury

Answer 2

stress

injury

Question 3

what adaptations occur upon stress to the cell

Answer 3

hyperplasia - inc in num
hypertrophy
atrophy
metaplasia

Question 4

what does injury to the cell lead to

Answer 4

necrosis or apoptosis

Question 5

targets to cell injury

Answer 5

energy metabolism
cell membrane
protein synthesis
genes

Question 6

explain injury to energy metabolism

Answer 6

hypoxia or mitochondrial dysfunction prevents formation of ATP
lactic acid build up due to anaerobic respiraton

Question 7

membrane damage

Answer 7

damage to phospholipid can lead to lysis

mitochondria - impairs energy metabolism

Question 8

damage to lysosomes

Answer 8

releases hydrolytic membranes

cells may digest themselves

Question 9

damage to ER

Answer 9

interferes with protein synthesis

Question 10

what does calcium affect

Answer 10

ATPase - decrease in ATP
phospolipase - breakdown of phospholipid
proteases - cytoskeletal digestion

Question 11

how can calcium homeostasis be lost

Answer 11

damage to membranes, influx of Ca from organelles

Question 12

how are free radicals produced

Answer 12

radiation

Question 13

examples of radical

Answer 13

hydroxyl
hydrogen peroxide
superoxide anion

Question 14

what counteract radicals

Answer 14

SOD (superoxide dismutase)
Vitamin K
Catalase
Vitamin E

Question 15

how is the superoxide anion neutralsied

Answer 15

using SOD to H202

catalase to water

Question 16

what are neutralisers of free radicals called

Answer 16

anti oxidants

Question 17

what do free radicals do

Answer 17

initiate chain reactiosn

Question 18

effects of reactive oxygen species

Answer 18

membrane damage
cross link proteins
DNA strand breakage

Question 19

linking common signals example

Answer 19

damage to mitochondrial membrane
release of Ca into cell (affecting Ca homeostasis)
increase activity of ATPase
depletion of ATP in cell
may lead to some membrane pumps not working

Question 20

necrosis VS apoptosis

Answer 20

affects many cells VS 1
causes secondary inflammatory vs no secondary effect
cell swelling vs cell shrinkage
disruption to the membrane vs no disruption (membrane blebbing)
random fragmentation of nucleus vs DNA laddering, nuclear condensation dissolution

Question 21

what happens to the apoptotic bodies

Answer 21

consumed by leukocytes

Question 22

types of necrosis

Answer 22

coagulative
Fat
liquefactive
caseous

Question 23

what happens in coagulative necorsis

Answer 23

nucleus fades and dissolves (karyolysis)
nuclear fragmentation(karyorrhexis)

eosinophilic cytoplasm

Question 24

what causes coagulative necrosis

Answer 24

lack of blood supply

Question 25

what happens in liqefactive necross

Answer 25

tissue liquified by PMN(polymorphonuclear) enzymes

Question 26

what happens in caseous

Answer 26

combination of coagulative and liquefaction

Question 27

what happens in fat necrosis

Answer 27

release of pancreatic lipases in acute pancreatitis

Question 28

examples of cell damage and necrosis in dentistry

Answer 28

pupal necrosis 
interruption of blood supply
pulpits
abcess
osteonecrosis of jaw

Question 29

sequelae of cell injury

Answer 29

inflammation
repair
scar
fibrosis