Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Integrative Phys > Cells + Cell Injury > Flashcards

Cells + Cell Injury Flashcards

1
Q

What is cell injury?

A

Effect of stresses from changes in the internal and/or external environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does cellular response to injury depend on? (4)

A
  1. Type of cell and tissue involved
  2. Extent and type of injury
  3. Intracellular phenomena
  4. Morphological consequences
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are 3 types (levels) of stresses on a cell and how is it classified?

A
  1. Adaptations: normal cell is restored due to minor stressor
  2. Reversible cell injury: repair and heal due to moderate stressor
  3. Irreversible cell injury: severe and persistent stress resulting in cell death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some examples of adaptive cell injuries?

A
  • Atrophy, hypertrophy, hyperplasia, metaplasia, dysplasia.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some examples of reversible cell injuries?

A

Degenerations, subcellular alterations, intracellular accumulations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

T/F - Cell injury can be both genetic and acquired.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is ischemia?

A

Loss of arterial blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is hypoxia?

A

Loss of ability to carry on sufficient aerobic oxidative respiration (ischemia can lead to hypoxia).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the most common cause of injury?

A

Hypoxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How can ischemia cause hypoxia? (2)

A
  1. Local causes: the occlusion of arteries or veins or the shunting of blood elsewhere.
  2. Systemic causes: failure of heart to pump enough blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is hypoxemia?

A

Too little available oxygen in the blood.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What causes oxygen problems in hypoxemia?

A
  1. Too little oxygen in the air
  2. Failure to properly ventilate the lungs
  3. Failure of lungs to properly oxygenate blood
  4. Failure of heart to pump enough blood through lungs
  5. Increased lung dead space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What causes hemoglobin problems in hypoxemia?

A
  1. Inadequate circulating red cell mass (anemia)
  2. Inability of hemoglobin to carry oxygen because of either CO poisoning or methemoglobinemia
  3. High affinity hemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are three causes of hypoxia?

A
  1. Ischemia
  2. Hypoxemia
  3. Failure of cytochromes (histotoxic hypoxia)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How can failure of cytochromes cause hypoxia?

A
  • CO and cyanide poisoning

- DNP poisoning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does DNP poisoning cause failure of cytochromes?

A
  • Proton leakage will cause uncoupling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens if uncoupling of protons takes place in ETC?

A

Results in insufficient production of ATP and instead everything is released as heat.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How do metabolic demands affect cells?

A

Increased metabolic demands will exacerbate hypoxic conditions temporarily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are some physical causes of cell damage?

A
  • mechanical trauma
  • thermal trauma
  • electricity
  • rapid pressure changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some examples of rapid pressure changes causing damage of cells?

A
  • Intracranial pressure
  • tumors
  • lung disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are some chemical causes of cell damage?

A
  • Oxygen in high concentrations
  • Hypertonic glucose
  • Alcohol and narcotics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are some microbial causes of cell damage?

A
  • Bacteria, fungi, viruses, protozoa and metazoa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do cytolytic and cytopathic viruses cause cell damage?

A

Cytolytic viruses: scramble genes that are needed to maintain cell structure and multiply so fast that cells explode
- Cytopathic: alter morphology

24
Q

What are some immunologic causes of cell damage?

A
  • hypersensitivity reactions
  • anaphylactic reactions
  • autoimmune disease due to auto-antibodies
25
Q

What are some nutritional derangement causes of cell damage? (2)

A
  1. Deficiency
    - overall starvation
    - Kwashiorkor (protein deficiency in later years) and marasmus (protein deficiency in earlier years)
  2. lack of glucose leading to same brain damage as hypoxia
26
Q

How does aging contribute to cell injury?

A

The impaired ability to replicate and repair eventually leads to cell death

27
Q

What can be an example of an idiopathic cause of cell injury?

A

Essential hypertension or cancer

28
Q

What happens when a small dose of toxin or short duration of ischemia is experienced?

A

Damage is reversible

29
Q

What happens when a large dose of toxin or persistent ischemia is experienced?

A

Will result in cell death

30
Q

How do skeletal muscles respond to hypoxia?

A

They can withstand hypoxia for a long time

31
Q

How do cardiac muscles respond to hypoxia?

A

Irreversible damage after about 20-30 minutes of ischemia

32
Q

How do neurons respond to hypoxia?

A

Will die after 3-5 minutes without oxygen

33
Q

How do liver cells respond to hypoxia?

A

Can last about 1-2 hours without oxygen

34
Q

How does intracellular phenomena affect cell damage? (3)

A
  1. Mitochondrial damage (the depletion of ATP)
  2. Cell membrane damage (disturbs metabolic and transmembrane exchange)
  3. Release of toxic free radicals
35
Q

Pathogenesis of hypoxia and ischemic reversible injuries

A
  1. Decreased ATP
  2. Intracellular lactic acidosis
  3. Damage to plasma membrane pumps
  4. Reduced protein synthesis
36
Q

Relationship between ischemia and aerobic respiration

A
  • In ischemia, aerobic respiration and glucose availability is compromised resulting in severe and faster effects of cell injury and accumulation of wastes in cells
37
Q

Relationship between hypoxia and anaerobic respiration

A
  • In hypoxia, anaerobic glycolytic ATP generation is able to continue to result in a less severe injury
38
Q

Why do specialized cells (such as myocardium, PT cells, and neurons) suffer effects of ischemia more rapidly and severely?

A

Because they depend solely on aerobic respiration for ATP

39
Q

How do ischemia and hypoxia lead to intracellular lactic acidosis?

A

Aerobic respiration will eventually fail and switch to anaerobic which causes glycogen depletion and lactic acid accumulation

40
Q

Why does the forced switch to anaerobic respiration cause glycogen depletion and lactic acid accumulation?

A

Because glucose and glycogen are needed to start anaerobic glycolysis and results in an end product of pyruvate and lactate

41
Q

How do ischemia and hypoxia lead to damage to plasma membrane pumps?

A

A lack of ATP interferes with the generation of phospholipids which in turn damages the pumps

42
Q

How are sodium-potassium pumps affected by ischemia and hypoxia (Na+ out, K- in)

A

Intracellular sodium will accumulate while potassium will passively flow out causing intracellular water and hydropic swelling

43
Q

How are calcium pumps affected by ischemia and hypoxia?

A

When membrane is damaged, excess calcium will move into the cell

44
Q

How does reduced protein synthesis progress from ischemia and hypoxia?

A
  • membranes of ER and Golgi will swell
  • ribosomes will detach from RER
  • polysomes will degrade to monosomes (inactivated)
45
Q

What makes cell injury irreversible? (2)

A
  1. mitochondrial dysfunction not reversible upon reperfusion or re-oxygenation
  2. disturbance in cell membrane function
46
Q

What are biochemical changes that affect ultrastructure? (5)

A
  1. Calcium influx
  2. Activated phospholipases
  3. Intracellular proteases
  4. Activated endonucleases
    Lysosomal hydrolytic enzymes
47
Q

How does calcium influx affect ultrastructure?

A

Large influx of calcium collects in mitochondria and disables function

48
Q

How do activated phospholipases affect ultrastructure?

A
  • Cause membrane damage

- The low replacement and synthesis of phospholipids results in low ATP and activated ATPase

49
Q

How do intracellular proteases affect ultrastructure?

A
  • Cause cytoskeletal damage
50
Q

How do activated endonucleases affect ultrastructure?

A

Nucleoproteins are damaged by lysosomal enzymes

51
Q

What are 3 forms of irreversible nuclear damage?

A
  1. Karyolysis: nuclear fading
  2. Pyknosis: nuclear shrinkage
  3. Karyorrhexis: nuclear fragmentation
52
Q

What do karyolysis, pyknosis, and karyorrhexis all lead to?

A

Nuclear dissolution and a nuclear necrotic cell

53
Q

How do lysosomal hydrolytic enzymes affect ultrastructure?

A

The damage of lysosomes releases hydrolytic enzymes that lead to the digestion of cellular components and cell death

54
Q

How are hydrolytic enzymes activated?

A

by low oxygen and pH

55
Q

What are dead cells replaced by?

A

Myelin figures

56
Q

What are the clinical parameters of cell death?

A

When liberated enzymes leak into serum

Integrative Phys (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions