Apoptosis

Question 1

plasma membrane events

Answer 1

little ATP, membrane ion pumps fail, H2O floods in, cell swells and burts. Phosphatidylserine on inner leaflet, external during apoptosis. Induces phagocytosis by next cell.

Question 2

cytoplasmic events

Answer 2

activation of caspases

Question 3

nuclear events

Answer 3

nuclear collapse, DNA shrink and breaks up. Concentration of chromatin on rim of the nucleus just before collapse. Endonucleases clip DNA inbetween nucleosomes (300 cuts per chromosome).

Question 4

tissue with most apoptosis

Answer 4

lymphocyte repair little and then go to apoptosis.

Question 5

tissue with least apoptosis

Answer 5

macrophages have lots of repait and little apoptosis

Question 6

Caspases role

Answer 6

extrinsic pathway ligand on killer T-cell finds to Fas, which finds to FADD, binds to caspase 8, which goes to caspase 3. FLIP gene/protein cancels this. Virus use FLIP

Question 7

mitochondrion role

Answer 7

Intrinsic pathway associates with Bcl-2 (anti-apoptotic), Bim and PUMA (proapoptotic) come to mito and antagonize until Cyt C is released into cytoplasm. Cyt C connects to Apaf-1, which activates Caspase 9, which activates caspase 3. Thus apoptosis

Question 8

Caspase 8

Answer 8

induces caspase 3 in extrinsic pathway

Question 9

Caspase 9

Answer 9

main initiator caspase of the intrinsic pathway for apoptosis

Question 10

Caspase 3

Answer 10

executioner caspase

Question 11

apoptosis and tumors

Answer 11

apoptosis prevents tumor progression, without it more tumors

Question 12

mechanism of one cell induce apoptosis on another

Answer 12

extrinsic pathway mechanism

Question 13

example of cell to cell apoptosis

Answer 13

Killer T cells inducing apoptosis