1.3 Apoptosis

Question 0

Apoptosis is seen in…(4)

Answer 0

Senescent cells
Embryo development
Immune mediated death…..cytotoxic t cells
Hormonal or cytokine withdrawl….results in dec cells via apop

Question 1

Apoptosis literally means

Answer 1

leaves falling from the tree

Question 2

Cell swelling is seen in…..

Answer 2

Necrosis

Question 3

Cell shrinking is seen in….

Answer 3

Apoptosis

Question 4

A morphological expression of cell death

Answer 4

necrosis

Question 5

controlled by specific genes

Answer 5

apoptosis

Question 6

physiological cell death or programmed cell death

Answer 6

apoptosis

Question 7

generally initiated by overwhelming stress

Answer 7

necrosis

Question 8

Inflammatory response

Answer 8

necrosis

Question 9

fragmentation of DNA and nucleus with blebbing

Answer 9

apoptosis (apoptotic bodies)

Question 10

how are apoptotic bodies cleared?

Answer 10

phagocytized quickly

• -phosphatidyl serine put on surface to tag it for phagocytosis
• -no inflammation

Question 11

Defining features of apoptosis (6)

Answer 11

cell shrinkage
membrane blebs
nuclear shrinkage/pyknosis-------look for size--shrinking says apop
nuclear fragmentation
phagocytosis by neighbor cells

Question 12

steps in apoptosis (3)

Answer 12

• early–chromatin margination and condensation
• later–nuclear fragmentation
• phagocytosis by adjacent cells

Question 13

stimulus for necrosis vs apoptosis

Answer 13

more severe vs less severe

Question 14

consequences of necrosis (3)

Answer 14

loss of functional tissue
impaired organ fn (transient or permanent)
inflammation

Question 15

consequences of apoptosiss

Answer 15

removal of damaged or unnecessary cells

Question 16

cell number/stages of necrosis

Answer 16

all cells

Question 17

cell number/ stages of apoptosis

Answer 17

different levels and stages

Question 18

pathological apoptosis (10)

Answer 18

ionizing radiation
free radical generation
mild thermal injury <43 deg C
steroids
glucocorticoids induce apop in lymphocytes
viral infection
cell mediated immunity
autoimmune diseases
degenerative diseases of the CNS azheimers, parkinsons 
neoplasia (if apop is inhibited)

Question 19

control of intracellular environment is lost

Answer 19

necrosis

Question 20

chromatin marginates early while injury is still reversible

Answer 20

necrosis

Question 21

cleavage at multiples of 200 bp (ladder on gel)

Answer 21

apoptosis

Question 22

loss of membrane integrity….necrosis vs apoptosis

Answer 22

early vs late

Question 23

nuclear events …..necrosis vs apoptosis

Answer 23

nuclear disintegration vs (condensation +fragmentation)

Question 24

Mechanisms of apoptosis (4)

Answer 24

signaling pathways control and integration common execution pathways phagocytosis and removal of dead cells

Question 25

Extrinsic pathway/receptor pathway uses

Answer 25

TRAILs (tumor necrosis factor related apoptosis inducing ligands) ex. TNF, FAS(CD95)/FASL

Question 26

Intrinsic pathway (mitochondrial) uses

Answer 26

Bcl2, Bax, p53 release Cyt c, Smac, DIABLO

Question 27

extrinsic initiating caspases

Answer 27

8 and 10

Question 28

intrinsic initiating caspases

Answer 28

9 and 12

Question 29

Execution caspases

Answer 29

3, 6, 7

Question 30

TNF does what?

Answer 30

depends on the receptor signaling....different things for different cells

Question 31

potential induced activity vs inhibitor capacity

Answer 31

> | inhibition is mostly jut to prevent accidental activation

Question 32

in nematodes ced3 an ced 4

Answer 32

are required for apoptosis | not transcriptionally regulated, always around-->zymogens

Question 33

in nematodes ced 9

Answer 33

blocks apoptosis -- if absent then lethal and excess will disrupt development

Question 34

Bcl2 blocks apop by.....and is found in....

Answer 34

inhibiting mitochondrial permeability keeping cyt c in mito; also binds apaf1 B cells translocation linking gene for IgG promoter leads to B cell lymphoma

Question 35

Bax

Answer 35

causes apoptosis upregulaated by p53 homo and heterodimers of bcl2 and bax determine if apop is blocked or not

Question 36

bid

Answer 36

helps bridge extrinsic and intrinsic pathways

Question 37

human homolog of ced 4

Answer 37

Apaf 1.....w/ cyt C it activatees caspase 9

Question 38

caspases are ........ proteases thta cleave proteins at .......residues

Answer 38

cysteine aspartic acid homologs too ced 3

Question 39

how do caspases disassemble a cell

Answer 39

inactivate inhibitors of apoptosis cleave structural proteins deregulate proteins by separating regulatory and catalytic subunits

Question 40

Caspase Activation (6)

Answer 40

``` protein cleavage protein cross links cell shrinkage nuclease activation nuclear shrinkage DNA fragmentation ```

Question 41

Extrinsic Pathway is mainly involved in.....mediated by.......

Answer 41

normal control of cell/growth survival TRAIL ligands binding death receptors; receptors aggregate, death domains of these receptors bind adaptor proteins with death domains (FADD and TRADD); bind several caspase 8 molecules inducing proximity and autocatalytic activation

Question 42

FADD

Answer 42

fas associated death domain

Question 43

TRADD

Answer 43

tnf receptor associated death domain

Question 44

cflip

Answer 44

competitively binds death domains preventing procaspase 8 from binding and getting activated......need overwhelming signal to overrcome

Question 45

intrinsic pathway is mainly involved in... and is mediated by......

Answer 45

injury induced apoptosis (to mitochondria, dna damage, protein damage, or T cell mediated kill) mitochondrial leakage of Cyt C, smac, diablo

Question 46

smac and diablo

Answer 46

eat up inhibitory capacity

Question 47

p53

Answer 47

facilitates apoptosis; inc bax that eats up bcl2, stopping inhibition, promoting apop not req. for steroid induced apop of lymphocytes radiation inc. p53--> tumors

Question 48

how are denatured/misfolded proteins handled (3)

Answer 48

heat-shock proteins----refold them ubiquitin tag/proteosome---degraded them caspase 12 activation---when other 2 systems are overloaded

Question 49

t-cell grazymes kill by

Answer 49

activating caspase 3

Question 50

IAPs

Answer 50

inhibitors of apoptosis proteins inhibit caspase 3 activation ex. survivin inhibited by smac/deablo