Injuries to cells Flashcards Preview

Pathology (m) > Injuries to cells > Flashcards

Flashcards in Injuries to cells Deck (33):
1

Name the 5 branches of pathology

Histology
Haemotology
Immunology
Chemical pathology
Microbiology

2

Name the to ways cells respond to stress

Adaption
Injury

3

Injury can be either

Reversible
Irreversible

4

If injury is irreversible this results in what?

Cell death

5

What are the two types of cell death?

Apoptosis
Necrosis

6

Name the different types of cell adaption...

Hyperplasia
Hypertrophy
Atrophy
Metplasia

7

Define hyperplasia

Increase in cell number
(Can lead to hypertrophy)
Can be pathological/physiological

8

Define hypertrophy

Increase in cell size
(Can cause increase size of organ)
Can be pathological/physiological

9

Define atrophy

Decrease in cell size

10

What can cause atrophy?

Decrease workload
Decrease blood supply
Inadequate nutrition
Loss of hormonal stimulus
Ageing

11

Define metplasia

One cell replaced by another cell
E.g. oesophagus
*Can be reversible

12

What are the 3 most common causes of cellular injury

Hypoxia (low o2)
Ischaemia (loss of blood supply)
Chemical damage (alcohol etc)

13

Name other causes of cellular injury

Radiation
Lack of nutrients
Infection
Ageing
Immunological changes

14

What are the 2 most common finding within reversible cellular injury (morphology)?

Cellular swelling
Fatty change

15

Out of necrosis and apoptosis which process is ALWAYS pathological?

Necrosis

16

Out of necrosis and apoptosis which causes local inflammation and why?

Necrosis due to cell swelling of cell that then ruptures

17

Out of necrosis and apoptosis which is known as a programmed cell death?

Apoptosis

18

Why does necrosis occur?

Due to damage of the cell membrane which then allows enzymes to digest the cell

19

Name a common type of necrosis...

Ischaemic necrosis

20

What causes apoptosis...

Damage to DNA/protein structures resulting in cell death

21

State the process of apoptosis...

Cell starts to break into small fragments
Fragments have signals on them that attract resident macrophages
Resident macrophages come and phagocytose
No cellular leakage meaning no danger of inflammatory response

22

Physiological apoptosis is meant to occur when?

Embryogenesis (excess tissue is programmed to die away if this doesn't happen this is bad)
Involution of hormone dependant tissues upon hormone deprivation (e.g. uterus post menopause becomes atrophic and small)
Elimination of cells after they have served their purpose
Elimination of potentially self-reactive lymphocytes

23

When does pathological apoptosis occur?

DNA damage
Accumulation of misfiled proteins
Infection
Cell death induced by cytotoxic T cells
Pathological atrophy in parenchymal organs after duct obstruction

24

Apoptosis results from what type of enzymes?

Caspases

25

What are the 2 main pathways that result in activation cell death pathway?

Mitrochondrial pathway (intrinsic)
Fas death receptor pathway (extrinsic)

26

Name the 4 main types of necrosis

Coagulative (commonly occurs after infections/loss of blood supply- most common- causes heart attack/myocardial infarct)
Fat (death of fat tissue due to activation of lypases)
Caseous (usually means TB unless proven otherwise)
Liquefactive (typical of the brain when infarct- hole in the brain)

27

How do cells become injured?

ATP depletion
Mitchondrial damage
Influx of calcium
Oxidative stress
Damage of cell membrane
DNA damage
Intracellular accumulation of abnormal material e.g fat cholesterol and proteins

28

ATP depletion causes what?

Decrease in cellular energy
It also effects sodium pump which can cause electrolyte imbalances

29

Mitochondrial damage results in what?

Decreased levels of ATP

30

An influx of calcium leads to what?

Activation of enzymes which can trigger apoptosis and programme cell death

31

Damage to cell membrane results in what?

Necrosis

32

Give an example of DNA damage

Radiation

33

Give the 3 examples of accumulation of abnormal materials

Fat
Cholesterol
Protein