Chapter 18: Apoptosis
Programmed cell death occurs ________________. (a)by means of an intracellular suicide program (b)rarely and during plant development (c)only in unhealthy or abnormal cells (d)only during embryonic development
Answer: (a)by means of an intracellular suicide program
Apoptosis differs from necrosis in that necrosis ________________. (a)requires the reception of an extracellular signal (b)causes DNA to fragment (c)causes cells to swell and burst, whereas apoptotic cells shrink and condense (d)involves a caspase cascade
Answer: (c)causes cells to swell and burst, whereas apoptotic cells shrink and condense
Which of the following statements regarding Fas-mediated programmed cell death is false? A) Fas ligand binding with Fas receptor stimulates a specific G protein. B) Fas ligand and receptor interaction results in the recruitment of adaptor proteins in the target cell. C) Capases are activated in the process. D) The caspase cascade results in the cleavage of the proteins within the target cell.
Answer: A) Fas ligand binding with Fas receptor stimulates a specific G protein.
Killer lymphocytes can elicit self-destruct mechanisms in target cells by interacting with A) Fas ligand. B) Fas receptors. C) Ras ligand. D) adaptor protein
Answer: B) Fas receptors.
All of the following participate in apoptosis except A) caspases. B) death-promoting proteins. C) mitochondria. D) Bcl-2
Answer: D) Bcl-2
Protein whose overexpression in a cancer cell inhibit apoptosis are: a.IAP b. Bcl-2 c.Akt kinase active-c d.all of them
Answer: a.IAP
Which of the following mutations in proteins involved in apoptosis will be expected to have dominant-negative phenotype (to cause a defect in apoptosis even in cells that also contain the normal protein): A.Deletion of death domain of Fas death receptor. B.Mutation of the catalytic cysteine of caspase-8 to serine. C.Mutational change to IAP that increases its affinity for caspases. D.all of them
Answer: d. all of them
Which of the following statements about apoptosis is true? (a)Cells that constitutively express Bcl2 will be more prone to undergo apoptosis. (b)The prodomain of procaspases contains the catalytic activity necessary for procaspase activation. (c)Bax and Bak promote apoptosis by binding to procaspases in the apoptosome. (d)Apoptosis is promoted by the release of cytochrome c into the cytosol from mitochondria.
answer: (d)Apoptosis is promoted by the release of cytochrome c into the cytosol from mitochondria.
Mice lacking the ability to make caspase-9 die as the result of numerous defects. During the necropsy (animal autopsy) of the animal you note that the brains of these mice are A) unregulated growth of the nerve cells. B) lack of apoptosis of some cells. C) overstimulation of G-protein-mediated transduction. D) overproduction of G receptor
answer: B) lack of apoptosis of some cells.
Protein whose elimination in a cancer cell inhibit apoptosis. a.Fas receptor b.procaspase c.Apaf-1 d.all of them
answer: d.all of them
Protein whose elimination in a cancer cell inhibit apoptosis. a. BH3 b. BH123 c.Bax d. anti-IAP e.all of them
answer: e.all of them
