Deck 30: Cell Birth, Lineage, and Death

Question 1

The use of cell-based models to understand or treat human disease processes is aided by stem cells in all the following ways,except:

A)growth of neurons in cell culture containing mutations associated with ALS for drug screening.
B)culture of patient-specific cells to replace those lost to disease,such as for type 2 diabetes.
C)differentiation of neurons from iPS cells to replace those damaged by neurodegenerative diseases.
D)provides proof that ES cells are pluripotent and can divide to make a normal animal.

Answer 1

D

Question 2

In mammalian development,which of the following is the correct chronological order of events?

A)blastocyst,zygote,four-cell,compacted morula,
B)zygote,four-cell,compacted morula,blastocyst
C)compacted morula,blastocyst,zygote,four-cell
D)four-cell,compacted morula,blastocyst,zygote

Answer 2

B

Question 3

The first differentiation event following fertilization occurs when:

A)the morula separates from the blastocyst.
B)the trophoectoderm separates from the inner cell mass.
C)the four-cell stage undergoes cleavage to generate the eight-cell stage.
D)the zygote divides to form two cells.

Answer 3

B

Question 4

Which of the following genes are expressed exclusively in pluripotent embryonic stem cells?

A)Nanog
B)Sox2
C)Oct4
D)Nanog and Oct4

Question 5

Briefly describe how Yamanaka and colleagues induced differentiated cells to form stem cells.

Question 6

Describe how Cre recombinase is used in lineage-tracing studies to follow the fate of Lgr5⁺-expressing intestinal stem cells.

Question 7

Fully differentiated mouse fibroblasts can be reprogrammed or induced to form pluripotent stem cells when transfected with retroviral vectors that express:

A)KLF4.
B)c-MYC.
C)SOX2.
D)all of the above

Question 8

In the Drosophila ovary,which of the following proteins is secreted from the cap cell and is responsible for creating and maintaining the niche for germ-line stem cells?

A)Hedgehog
B)FGF
C)Arm
D)Ptc

Question 9

Dolly,the famous sheep,was cloned using:

A)induced pluripotent stem cells.
B)homologous recombination.
C)somatic cell nuclear transfer.
D)Cre recombinase.

Question 10

How can somatic cell nuclear transfer be used to clone a mouse?

Question 11

Describe gamete fusion that occurs during mammalian fertilization.

Question 12

Which of the following is(are)in the cell lineage that gives rise to T cells?

A)GM-CFC
B)myeloid stem cell
C)pluripotent hematopoietic stem cell
D)myeloid stem cell and pluripotent hematopoietic stem cell

Question 13

Define stem cells.Which of the following cells are stem cells: (a)fertilized egg, (b)intestinal crypt cell, (c)granulocyte-macrophage colony-forming cell (GM-CFC)?

Question 14

Which of the following provides evidence for the role of Paneth cells in supporting the intestinal stem cell niche?

A)Mutant mice with reduced numbers of Paneth cells have fewer intestinal stem cells.
B)Co-culture of Paneth cells with intestinal stem cells leads to formation of villus-like structures.
C)Paneth cells produce Wnt.
D)all of the above

Question 15

Which of the following is FALSE regarding the stem cells located in the epithelial lining of the small intestine?

A)They express β-catenin.
B)Lgr5 encodes an R-spondin receptor.
C)The Lgr5 gene is induced by Wnt signaling.
D)They are located in pits called crypts.

Question 16

In the mouse embryo,pluripotent stem cells are found in the:

A)inner cell mass.
B)trophectoderm.
C)zona pellucida.
D)blastocoel.

Question 17

The mating projection or shmoo in budding yeast cells relies on having:

A)Cdc42 recruited and localized to the region near the highest concentration of mating pheromone.
B)formin proteins to nucleate the assembly of actin filaments.
C)myosin V to move secretory vesicles to the plus (+)ends of microfilaments.
D)all of the above

Question 18

Floral meristems give rise to:

A)leaves.
B)petals.
C)stamens.
D)petals and stamens.

Question 19

Describe how the stem cell niche contributes to the maintenance of germ-line stem cells in Drosophila.

Question 20

Daughter cells that form as a result of asymmetric cell division may differ in:

A)size.
B)shape.
C)protein composition.
D)all of the above

Question 21

When a cell divides asymmetrically:

A)PAR proteins are spread homogenously throughout the cell.
B)the spindle orients the new daughter cell toward the niche cell.
C)exogenous factors bind cell surface receptors to induce actin cytoskeletal rearrangements.
D)the resulting two cells are identical to each other.

Question 22

Which is the correct combination of proteins in polarized cells involved in planar-cell polarity?

A)Flamingo-Strabismus on one side and Dishevelled-Frizzled on the other
B)Frizzled-Strabismus on one side and Flamingo-Dishevelled on the other
C)Strabismus-Dishevelled on one side and Flamingo-Frizzled on the other
D)none of the above

Question 23

Describe two ways that stem cells can be induced to divide asymmetrically.

Question 24

Which of the following triggers apoptosis?

A)Fas ligand
B)NGF
C)TNFα
D)Fas ligand and TNFα

Question 25

Even before the first cell division,the one-cell C.elegans zygote has an asymmetric distribution of:

A)Par3 and aPKC in the cortex of the posterior half of the cell.
B)Par6 in the cortex of the posterior half of the cell.
C)Par2 in the cortex of the posterior half of the cell.
D)all of the above

Question 26

XIAP proteins:

A)inhibit initiator and effector caspases.
B)are released from the mitochondria through Bad/Bax oliogomers.
C)are activated by SMAC/DIABLO proteins.
D)cleave the cytoskeleton during apoptosis.

Question 27

Epithelial cell tight junctions recruit:

A)Crumbs complexes.
B)Scribble complexes.
C)apical PAR complexes.
D)all of the above

Question 28

The apical-basolateral polarity of epithelial cells depends on which one of the following?

A)the Scribble complex in the apical domain of the cell
B)the Crumbs complex in the basal domain of the cell
C)the interaction between nectin and JAM-A
D)all of the above

Question 29

Mitochondrial permeabilization can be induced by compounds that poke small holes in the outer membrane.This would cause:

A)cytochrome c to be released into the cytosol.
B)increased ATP synthesis through oxidative phosphorylation.
C)increased Bad-Bcl2 interactions.
D)upregulation of caspase expression.

Question 30

In C.elegans,which of the following is located in the lineage that gives rise to germ cells?

A)P1
B)P2
C)P3
D)all of the above

Question 31

Which of the following forms a dimer that gets displaced from the surface of the mitochondria by EGL-1?

A)CED-3
B)CED-4
C)CED-9
D)CED-8

Question 32

Apoptosis can be induced by a mitochondrial protein being released into the cytosol.This protein binds directly to what in the cytosol?

A)caspase 3
B)Bax
C)Bcl-2
D)Apaf-1

Question 33

In cells that have been signaled to die via TNF-a receptor signaling but lack caspase-8 activity:

A)apoptosis occurs via the other caspases.
B)necroptosis occurs downstream of RIP protein activation of MLKL.
C)the cell remains alive and viable.
D)none of the above

Question 34

Which of the following is a feature that defines a cell dying in response to tissue damage (necrosis)?

A)The nucleus condenses and then fragments.
B)Small membrane bodies are released and then engulfed by other cells.
C)The cell shrinks.
D)none of the above

Question 35

Which of the following genes encodes a caspase in C.elegans?

A)ced-3
B)ced-4
C)ced-9
D)ced-8

Question 36

Shmoo formation allows budding yeast to grow toward a concentration of mating factor.Describe how asymmetric changes in the haploid yeast cell promote the formation of this mating projection.

Question 37

Explain the role of mitochondria in apoptosis.

Question 38

Examination of a cell's structure reveals condensed chromatin,a shrunken cytoplasm,but unfragmented DNA and a lack of blebbing.If this cell has been triggered to undergo apoptosis by an extrinsic factor,which of the following events has NOT likely happened yet?

A)activation of a TNF-α receptor
B)recruitment of TRADD
C)recruitment of FADD
D)activation of caspases

Question 39

Which of the following apoptotic proteins is homologous to human Bcl-2?

A)CED-3
B)CED-4
C)CED-9
D)none of the above