Exam 1: Cell Injury

Question 1

how can cells be injured?

Answer 1

extrinsic injury and intrinsic injury, or both

Question 2

How can ATP be produced?

Answer 2

oxidative phosphorylation and anaerobic glycolysis

Question 3

ATP is essential for what processes

Answer 3

major synthetic and degradative processes

Question 4

depletion of ATP occurs with what?

Answer 4

hypoxia and toxin exposure

Question 5

loss of as little as ___ of ATP has widespread effects on many critical cellular systems

Answer 5

5-10%

Question 6

decreased ATP causes loss of activity of

Answer 6

Na-K ATPase pump

Question 7

loss off activity of the Na-K ATPase pump results in

Answer 7

Na accumulation in the cell and K loss

Question 8

what is hyropic degeneration

Answer 8

cell swelling and dysfunction due to water following Na into the cell

Question 9

decreased ATP causes rate of anaerobic glycolysis to _____

Answer 9

increase

Question 10

increase in anaerobic glycolysis leads to _____ glycogen stores, _____ lactic acid, ______ pH

Answer 10

reduced; increased; reduced

Question 11

reduced pH decreases activity of

Answer 11

many cellular enzymes

Question 12

decreased ATP leads to ____ of the Ca pump

Answer 12

failure

Question 13

failure of the Ca pump causes Ca _______

Answer 13

accumulation in the cell

Question 14

increased intracellular Ca does what to mitochondria

Answer 14

damages mitochondria

Question 15

increased intracellular Ca activates

Answer 15

enzymes that can damage cells

Question 16

as ATP depletion worsens, ribosomes ____

Answer 16

detach

Question 17

ribosome detachment results in

Answer 17

decreased protein synthesis

Question 18

ultimately, there is irreversible damge to ____

Answer 18

mitochondrial and lysosomal membranes

Question 19

free radicals

Answer 19

have a single unpaired electron in outer orbit

Question 20

energy created by such an unstable configuration is released through reactions with adjacent molecules such as

Answer 20

proteins, lipids, CHO, and nucleic acids

Question 21

Reactive oxygen species

Answer 21

free radicals normally produced during mitochondrial respiration; normally degraded and removed by cellular defense mechanisms

Question 22

what are exampls of ROS

Answer 22

superoxide and hydroxyl

Question 23

what are examples of enzymes that defend against ROS damage

Answer 23

superoxide dismutase
catalase
glutathione peroxidase

Question 24

oxidative stress

Answer 24

excess of ROS due to ROS increase or scavenging systems are ineffective

Question 25

what do antioxidants do

Answer 25

either block the initiation of free radical formation or inactivate free radicals (vitamin A, E, D)

Question 26

Cell membrane injury results in

Answer 26

increased permeability

Question 27

what can cause membrane damage

Answer 27

atp depletion and free radicals; bacterial toxins, viral proteins, lytic complement components, chemicals, and physical injury

Question 28

what are the most important sites of membrane damage

Answer 28

plasma membrane, mitochondrial membrane, and membranes of lysosomes

Question 29

plasma membrane injury results in

Answer 29

loss of osmotic balance and influx of water and ions such as Na and Ca

Question 30

mitochondrial membrane damage results in

Answer 30

decreased ATPp production and release of pro-apoptotic proteins

Question 31

loss of lysosomal membrane integrity results in

Answer 31

leakage of lysosomal enzymes into cytoplasma nd enzymatic degradation of proteins, RNA, DNA, and glycogen

Question 32

what are the 2 forms of cell death

Answer 32

necrosis and apoptosis

Question 33

morphologic changes during necrosis include

Answer 33

cell swelling increased eosinophilia nuclear changes

Question 34

increased eosinophilia is caused by

Answer 34

loss of RNA and denaturing of the cytoplasmic proteins that normally bind the red dye eosin

Question 35

pyknosis

Answer 35

shrinkage

Question 36

karyorrhexis

Answer 36

fragmentation

Question 37

karolysis

Answer 37

dissolution

Question 38

coagulative necrosis

Answer 38

architecture of dead tissues is preserved because lysosomal enzymes are dentatured along with structural proteins, so dad cells persist for days or even weeks

Question 39

coagulative necrosis often occurs in areas of

Answer 39

ischemia

Question 40

what is an infarct

Answer 40

necrosis secondary to ischemia

Question 41

liquefactive necrosis

Answer 41

architecture of the dead tissues is not preserved; dead cells are digested by lysosomal enzymes or enzymes secreted by leukocytes

Question 42

liquefactive necrosis is often seen in

Answer 42

bacterial and fungal infections

Question 43

fluid accumulations composed of necrotic neutrophils and tissue debris is called

Answer 43

pus

Question 44

caseous necrosis

Answer 44

necrotic issue has turned into a friable mass resembling cottage cheese

Question 45

gangrenous necrosis

Answer 45

ischemic necrosis with superimposed bacterial infection

Question 46

what is apoptosis

Answer 46

individual cell death that can be either physiologic or pathologic

Question 47

physiologic apoptosis occurs when

Answer 47

during embryogenesis and immune cell development when unneeded cells are removed

Question 48

pathologic apoptosis occurs when

Answer 48

viral infection, immunologic damage induced by Tlymphocytes, hypoxia, and some toxins

Question 49

what can induce apoptosis

Answer 49

direct injury to dna withdrawal of growth factors or hormones can lead to release of proapoptotic proteins from mitochondria receptor-ligan interactions (TNF binding to receptors in plasma membranes)

Question 50

enzymes called _____ activate other enzymes that break down DNA and cytoskeletal proteins

Answer 50

caspases

Question 51

what are the fragments of cells called that contain intracellular oranelles and other cytosolic components

Answer 51

apoptotic bodies

Question 52

apoptotic bodies are consumed by

Answer 52

phagocytes (macrophages)

Question 53

unlike necrotic cells that are often _____, apoptotic cells are ______

Answer 53

swollen, shrunken

Question 54

apoptotic cells are often ______ like necrotic cells

Answer 54

hypereosinophilic

Question 55

apoptotic bodies are often visible within

Answer 55

macrophages

Question 56

extrinsic pathway

Answer 56

TNF produced by leukocytes induces apoptosis by binding to receptors in plasma membranes

Question 57

intrinsic (mitochondrial) pathway

Answer 57

growth factors or hormones can lead to release of proapoptotic proteins from mitochondria