Cell Death Flashcards Preview

MD2002 > Cell Death > Flashcards

Flashcards in Cell Death Deck (40):
1

What can happen to mitochondria during reversible cell injury and what can this lead to?

Mitochondrial swelling and calcification leading to oxygen depletion & toxication

2

Will the endoplasmic reticulum constrict or dilate during cell injury?

Dilate

3

What will happen to ribosomes during reversible cell injury?

Ribosomes will become disaggregated

4

What is typical of lethal cell injury?

Inflammation ---> necrosis
Irreversible nature

5

Where can coagulative necrosis be observed?

Most tissues (firm pale area with ghost outlines)
Proteins

6

Where can colliquative necrosis be observed?

In the brain (dead area is liquified)
Lipids

7

Where can caseous necrosis be observed?

In tuberculosis (pale yellow semi-solid material)

8

Where can fibrinoid necrosis be observed?

Arterioles in malignant hypertension

9

Where can fat necrosis be observed?

Following trauma or following pancreatitis

10

What is gangrene?

Necrosis with putrefaction

11

Name some causes of necrosis.

Ischaemia
Metabolic causes
Trauma

12

How does Programmed Cell Death (PCD) differ from Apoptosis?

Apoptosis is morphological (has a set structure and form that it takes in breaking down each cell, regardless of what cell type it is

13

Give three examples of apoptosis.

Answers include:
Embryology and formation of lumen of tubes
Response to growth signals including the menstrual cycle
Inflammation including its resolution and the death of neutrophils
Immune defence - T and NK cell responses
Tumour prevention - prevent mutation
Autoimmune diseases and their self destructing nature
HIV AIDS

14

Does apoptosis target single cells, tissues, or organs?

Single cells

15

How does apoptosis target the heart of the cell?

Involves DNA fragmentation

16

How does extrinsic apoptosis differ from intrinsic apoptosis?

Activation of apoptosis is from outside the cell in extrinsic apoptosis whereas in intrinsic apoptosis, it it from the inside of the cell

17

Name some examples of intrinsic apoptosis.

Stress (e.g. oxidative)
DNA damage
p53
Cytochrome c leaks from mitochondrion causing caspase enzyme cascade

18

Name some examples of extrinsic apoptosis.

Receptors
T-cell immune response
TNF family binds to reeptor, activating caspase enzyme cascade

19

What is the function of p53?

p53 can tell a cell to repair itself, grow, or undergo apoptosis (via induced reverse transcriptase factor)

20

How are the apoptotic fragments/bodies carried away from the site of apoptosis?

Macrophages or non-professional phagocytes (e.g. epithelial cells) recognise the fragments and immediately ingest them

21

What is the function of the bcl-2 family of proteins?

Regulate cell death

22

What types of bcl-2 family proteins are there?

Bcl2
BH123
BH3

23

What effect do Bcl2 proteins have on apoptosis?

Inhibit (anti) apoptosis

24

What effect do BH123 proteins have on apoptosis?

Allow (pro) apoptosis

25

What effect do BH3 protein have on apoptosis?

Allow (pro) apoptosis

26

Give some example of Bcl2 proteins.

Bcl2
Bcl-XL

27

Give some examples of BH123 proteins.

Bax
Bak

28

Give some examples of BH3 proteins

Bad
Bim
Bid
Puma
Noxa

29

What can abnormal (over-) expression of Bcl2 lead to?

Cancer

30

What effect does IAP have on apoptosis?

Inhibits apoptosis

31

What are Caspases?

Have cysteine in their active sites 'C'
Cleavage after aspartate 'asp'
Are proteases 'ase'

32

What do caspases do?

Cleave ICAD (destroy genetic information)
Cleave PARP (prevent DNA repair)
Cleave lamin (break down nuclear architecture)
Cleave keratin (break down cytoplasmic architecture)

33

What three factors can increase survival chances of a cell?

Bcl2 production increased (anti-apoptotic)
Inactivation of BH3 (pro-apoptotic)
Anti-IAP inactivation (IAP is anti-apoptosis, so destruction of anti IAP ---> decreased apoptosis

34

Which component can lymphoma target and disable?

Bcl2

35

Which component can Alzheimers Disease target and disable?

Caspase 3

36

Which component can cancer target and disable?

IAP

37

Name three things that can happen when apoptosis goes wrong

Autoimmune Disease
Cancer
Neurodegeneration

38

What is pyroptosis?

Highly inflammatory form of PCD that is commonly a response to infection by intracellular pathogens

39

Which 'features' of apoptosis are also present in necrosis?

Caspase 1 activation (NOT caspase 3)
Nuclear fragmentation (NOT cytoplasmic blebbing)
Pro-inflammatory

40

What is anoikis?

PCD after losing contact with the basement membrane/ECM