Chap 2- cell response to stress

Question 1

adaptation

Answer 1

• stress induced change in a cell

- can happen under normal or disease state

Question 2

types of adaptation

Answer 2

• hypertrophy
• hyperplasia
• atrophy
• metaplasia
• dysplasia

Question 3

Hypertrophy

Answer 3

• increase in cell size, no new cells added
• due to synthesis of proteins and other cellular organelles required
• happens in organs not capable of division

Question 4

Hyperplasia

Answer 4

• addition of new cells
• organ cells can multiply
• in response to GF

Question 5

Atrophy

Answer 5

• decrease in cell size and number

Question 6

Metaplasia

Answer 6

• change from one cell type to another, reversible

- protective mechanism

Question 7

Dysplasia

Answer 7

• cells become abnormal or more primitive
• severity ranges
• due to chronic irritation or inflammation

Question 8

Causes of cell injury

Answer 8

• hypoxia
• immune reactions
• ROS
• infection
• physical/ chemical agents
• genetics

Question 9

hypoxia

Answer 9

• limited oxygen carrying capacity

- does not limit bloods ability to carry other nutrients or waste

Question 10

ischemia

Answer 10

• reduced blood flow
• stops all nutrients/waste removal
• causes more rapid response and severe tissue damage compared to hypoxia

Question 11

mechanism of cell injury

Answer 11

Stress -> decreased ATP -> Loss of function of ion pumps -> cell swells

• in irreversible damage cell swells then bursts

Question 12

ischemia- reperfusion injury

Answer 12

• organ is damaged when blood supply is reestablished because cell function was weakened
• cannot reduce oxygen to water properly during oxidative phosphorylation -> ROS

Question 13

mechanism of reperfusion injury

Answer 13

• increased generation of ROS
• Intracellular Ca overload
• increased local inflammatory infiltrate
• complement activation

Question 14

ROS

Answer 14

• cause aging, necrosis, apoptosis
• generated in mitochondria
• too much damage leads to lipid peroxidation in p. membrane- unstable and reactive p. membrane
• can lead to protein modifications and DNA damage

Question 15

manifestation of cell injury

Answer 15

• accumulation of abnormal/toxic substance
• inadequate removal of normal substance
• abnormal endogenous substance accumulation
• substance accumulation due to enzyme deficiency

Question 16

steatosis

Answer 16

fatty change due to abnormal accumulation of TG

Question 17

intracellular protein accumulation can be due to

Answer 17

• excessive synthesis
• excessive reabsorption
• defects in cellular transport
• aggregation of abnormal proteins

Question 18

accumulation of pigments

Answer 18

• can cause cell damage

- can be due to exogenous or endogenous substances that we cannot metabolize

Question 19

dystrophic calcification

Answer 19

• abnormal deposition of Ca salts
• occurs in cells that are dying
• Ca levels in blood are normal

Question 20

metastatic calcification

Answer 20

• abnormal deposition of Ca salts

- happens in normal tissues under conditions of hypercalcemia

Question 21

where is calcium normally found

Answer 21

mitochondria and e.r.

Question 22

what is the hormone that maintains Ca levels?

Answer 22

parathyroid hormone

Question 23

principle causes of metastatic calcification

Answer 23

• elevated parathyroid hormone
• bone destruction
• vitamin- d disorders
• renal failure causing secondary hyperparathyroidism

Question 24

what is the role of vitamin d and ca?

Answer 24

vitamin d absorbs Ca, if excess in vitamin d then excess Ca is absorbed and leads to high levels of Ca in blood

Question 25

necrosis

Answer 25

- always pathological - due to external agents - ATP depleted -> membrane pumps fail -> ion imbalance -> water moves into cell -> swelling -> cell bursts

Question 26

types of necrosis

Answer 26

- coagulative - liquefactive - caseous - fatty

Question 27

coagulative necrosis

Answer 27

- loss of blood supply - tissue appears firm and opaque - happens in all organs except brain/neurons

Question 28

liquefactive necrosis

Answer 28

- loss of blood supply in the brains/neurons - fluid created by enzymes leaking outside of cell - fluid is so corrosive they digest other cells around them

Question 29

caseous necrosis

Answer 29

- looks like cheese | - occurs with mycobacterium tuberculosis and some fungal infections

Question 30

fatty necrosis

Answer 30

- occurs in issues that have a lot of fat - fat cells attacked by lipase, destroys fat cells - lipids combine with Ca to form Ca salts -> soapy/chalky look

Question 31

gangrene

Answer 31

necrosis + infection

Question 32

apoptosis

Answer 32

- programmed cell death - apoptotic cells break up into fragments called apoptotic bodies which are targets for phagocytes - normal or disease states - results from activation of enzyme caspases - minimal to no inflammation

Question 33

pathological causes of apoptosis

Answer 33

- DNA damage - accumulation of misfolded proteins - cell death in certain viral infections - cytotoxic t cells - pathologic atrophy

Question 34

autophagy

Answer 34

- cell eats its own contents, self cleansing process - delivery of cytoplasmic material to lysosome for degradation - normal and disease states

Question 35

when does autophagy occur?

Answer 35

- starvation - maintenance - aging - exercise - can be non-selective- cell eats anything and everything to survive