Question 1

Exposure of zebrafish nuclei to cytosol isolated from eggs at metaphase of mitosis resulted in phosphorylation of NEP55 and L68 proteins by cyclin-dependent kinase 2. NEP55 is a protein of the inner nuclear membrane, and L68 is a protein of the nuclear lamina. What is the most likely role of phosphorylation of these proteins in the process of mitosis?

Accepted Answer

A)   They enable the attachment of spindle microtubules to kinetochores.
B)   They are involved in chromosome condensation.
C)   They are involved in the disassembly of the nuclear envelope.
D)   They are involved in migration of centrosomes to opposite sides of the nucleus.E) A) and C)
F) All of the above

Question 2

Amount of DNA per nucleus over the cell division cycle.
G1 is represented by which numbered part(s)  of the cell division cycle in the accompanying figure?

Accepted Answer

A)   I and V
B)   II
C)   III
D)   IVE) A) and B)
F) B) and C)

Question 3

Which of the following pairs of molecules make up an active MPF?

Accepted Answer

A)   a growth factor and mitotic factor
B)   ATP synthetase and a protease
C)   cyclin and tubulin
D)   cyclin and a cyclin-dependent kinaseE) B) and D)
F) A) and D)

Question 4

The drug cytochalasin B blocks the polymerization of actin microfilaments. Which of the following events of the cell cycle in animal cells would be most directly disrupted by cytochalasin B?

Accepted Answer

A)   spindle formation
B)   spindle attachment to kinetochores
C)   movement of chromosomes to the poles during anaphase
D)   cleavage furrow formation and cytokinesisE) All of the above
F) A) and B)

Question 5

Which of the following statements best describes cells in culture that do not exhibit either density-dependent inhibition or anchorage dependence?

Accepted Answer

A)   The cells are unable to form spindle microtubules.
B)   The cells follow an altered series of cell cycle phases.
C)   The cells show characteristics of tumors.
D)   The cells have nonfunctional MPF.E) A) and B)
F) A) and C)

Question 6

If all chromosomes are not attached to the mitotic spindle at the M phase checkpoint, the cells would most likely be arrested at which of the following points in the cell division cycle or mitosis?

Accepted Answer

A)   telophase
B)   prophase
C)   G2
D)   metaphaseE) A) and B)
F) None of the above

Question 7

After DNA replication, each duplicated chromosome consists of two of which of the following structures?

Accepted Answer

A)   daughter chromosomes
B)   daughter nucleosomes
C)   sister chromatids
D)   sister chromatinsE) A) and B)
F) A) and C)

Question 8

Which of the following events would be most likely to produce cells with several nuclei?

Accepted Answer

A)   repeated cytokinesis without mitosis
B)   repeated mitosis with simultaneous cytokinesis
C)   repeated mitosis without cytokinesis
D)   multiple S phases without mitosisE) A) and C)
F) None of the above

Question 9

Which of the following statements best describes density-dependent inhibition?

Accepted Answer

A)   As cells become more numerous, they begin to squeeze against each other, restricting their size.
B)   As cells become more numerous, the cell surface proteins of one cell contact the adjoining cells, and they signal each other to stop dividing.
C)   As cells become more numerous, the protein kinases they produce begin to compete with each other, such that the proteins produced by one cell essentially cancel those produced by its neighbor.
D)   As cells become more numerous, the level of waste products increases, which slows metabolism and inhibits growth.E) A) and D)
F) A) and C)

Question 10

Movement of the chromosomes during anaphase would be most directly affected by a drug that prevents which of the following events?

Accepted Answer

A)   nuclear envelope breakdown
B)   elongation of microtubules
C)   shortening of microtubules
D)   formation of a cleavage furrowE) None of the above
F) C) and D)

Question 11

In a diploid cell with four chromosome pairs (2n = 8) , how many centromeres will be found in a nucleus at G2 of the cell division cycle?

Accepted Answer

A)   4
B)   8
C)   16
D)   32E) None of the above
F) B) and D)

Question 12

One type of eukaryotic cell (line 1)  spends 24 minutes in S phase and another type of cell (line 2)  spends 48 minutes in S phase. Which of the following statements is the best explanation for the difference in time spent in S phase by cell lines 1 and 2?  Amount of DNA per nucleus over the cell division cycle.

Accepted Answer

A)   Line 2 contains more DNA than line 1.
B)   Lines 1 and 2 contain the same amount of DNA.
C)   Line 1 cells reproduce by binary fission and line 2 cells reproduce by mitosis and cytokinesis.
D)   Line 2 has plant cells and line 1 has animal cells.E) A) and B)
F) C) and D)

Question 13

FtsZ is a bacterial protein that forms a contractile ring involved in binary fission. Its function is analogous to which of the following structures in eukaryotic cells?

Accepted Answer

A)   the cleavage furrow of eukaryotic animal cells
B)   the cell plate of eukaryotic plant cells
C)   the mitotic spindle of eukaryotic cells
D)   the microtubule-organizing center of eukaryotic cellsE) A) and D)
F) B) and C)

Question 14

Amount of DNA per nucleus over the cell division cycle.
Which numbered regions of the accompanying figure represent the DNA content associated with cells at metaphase?

Accepted Answer

A)   II and IV
B)   II only
C)   III only
D)   IV onlyE) None of the above
F) B) and D)

Question 15

Which of the following characteristics would be most important for a chemotherapeutic drug designed to treat cancer cells?

Accepted Answer

A)   It is safe enough to prevent all apoptosis.
B)   It does not interfere with metabolically active cells.
C)   It specifically inhibits cells entering G0.
D)   It specifically inhibits the cell division cycle in rapidly dividing cells.E) A) and C)
F) A) and B)

Question 16

Which of the following structures or molecules is required in order for motor proteins to facilitate movement of chromosomes toward the poles in mitosis?

Accepted Answer

A)   intact centromeres
B)   actin microfilaments
C)   ATP as an energy source
D)   intact cohesinE) None of the above
F) A) and C)

Question 17

Which of the following properties is associated with a cyclin-dependent kinase (Cdk) ?

Accepted Answer

A)   A Cdk is inactive, or "turned off," in the presence of a cyclin.
B)   The number of Cdk molecules increases during the S and G2 phases and decrease during M.
C)   A Cdk is an enzyme that catalyzes the attachment of kinetochores to microtubules.
D)   A Cdk is an enzyme that attaches phosphate groups to other proteins.E) None of the above
F) B) and D)

Question 18

Progression beyond the G2 checkpoint into mitosis is triggered by which of the following molecules?

Accepted Answer

A)   PDGF
B)   MPF
C)   cyclin
D)   CdkE) A) and B)
F) All of the above

Question 19

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?

Accepted Answer

A)   spindle formation
B)   spindle attachment to kinetochores
C)   cell elongation during anaphase
D)   cleavage furrow formation and cytokinesisE) B) and C)
F) All of the above

Question 20

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in ________.

Accepted Answer

A)   cells with more than one nucleus
B)   cells that are unusually small
C)   cells lacking nuclei
D)   cell cycles lacking an S phaseE) A) and D)
F) A) and C)

Exam 12: Mitosis

Amount of DNA per nucleus over the cell division cycle. G1 is represented by which numbered part(s) of the cell division cycle in the accompanying figure?

Correct Answer
verified

Correct Answer
verified

Which of the following statements best describes cells in culture that do not exhibit either density-dependent inhibition or anchorage dependence?

Correct Answer
verified

Which of the following structures or molecules is required in order for motor proteins to facilitate movement of chromosomes toward the poles in mitosis?

Correct Answer
verified

Which of the following properties is associated with a cyclin-dependent kinase (Cdk) ?

Correct Answer
verified

FtsZ is a bacterial protein that forms a contractile ring involved in binary fission. Its function is analogous to which of the following structures in eukaryotic cells?

Correct Answer
verified

Progression beyond the G2 checkpoint into mitosis is triggered by which of the following molecules?

Correct Answer
verified

Which of the following statements best describes density-dependent inhibition?

Correct Answer
verified

Movement of the chromosomes during anaphase would be most directly affected by a drug that prevents which of the following events?

Correct Answer
verified

Which of the following events would be most likely to produce cells with several nuclei?

Correct Answer
verified

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in ________.

Correct Answer
verified

In a diploid cell with four chromosome pairs (2n = 8) , how many centromeres will be found in a nucleus at G2 of the cell division cycle?

Correct Answer
verified

Which of the following pairs of molecules make up an active MPF?

Correct Answer
verified

Amount of DNA per nucleus over the cell division cycle. Which numbered regions of the accompanying figure represent the DNA content associated with cells at metaphase?

Correct Answer
verified

Correct Answer
verified

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?

Correct Answer
verified

Which of the following characteristics would be most important for a chemotherapeutic drug designed to treat cancer cells?

Correct Answer
verified

If all chromosomes are not attached to the mitotic spindle at the M phase checkpoint, the cells would most likely be arrested at which of the following points in the cell division cycle or mitosis?

Correct Answer
verified

The drug cytochalasin B blocks the polymerization of actin microfilaments. Which of the following events of the cell cycle in animal cells would be most directly disrupted by cytochalasin B?

Correct Answer
verified

After DNA replication, each duplicated chromosome consists of two of which of the following structures?

Correct Answer
verified

Exam 12: Mitosis

Amount of DNA per nucleus over the cell division cycle. G1 is represented by which numbered part(s) of the cell division cycle in the accompanying figure?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which of the following statements best describes cells in culture that do not exhibit either density-dependent inhibition or anchorage dependence?

Correct AnswerverifiedShow Answer

Which of the following structures or molecules is required in order for motor proteins to facilitate movement of chromosomes toward the poles in mitosis?

Correct AnswerverifiedShow Answer

Which of the following properties is associated with a cyclin-dependent kinase (Cdk) ?

Correct AnswerverifiedShow Answer

FtsZ is a bacterial protein that forms a contractile ring involved in binary fission. Its function is analogous to which of the following structures in eukaryotic cells?

Correct AnswerverifiedShow Answer

Progression beyond the G2 checkpoint into mitosis is triggered by which of the following molecules?

Correct AnswerverifiedShow Answer

Which of the following statements best describes density-dependent inhibition?

Correct AnswerverifiedShow Answer

Movement of the chromosomes during anaphase would be most directly affected by a drug that prevents which of the following events?

Correct AnswerverifiedShow Answer

Which of the following events would be most likely to produce cells with several nuclei?

Correct AnswerverifiedShow Answer

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in ________.

Correct AnswerverifiedShow Answer

In a diploid cell with four chromosome pairs (2n = 8) , how many centromeres will be found in a nucleus at G2 of the cell division cycle?

Correct AnswerverifiedShow Answer

Which of the following pairs of molecules make up an active MPF?

Correct AnswerverifiedShow Answer

Amount of DNA per nucleus over the cell division cycle. Which numbered regions of the accompanying figure represent the DNA content associated with cells at metaphase?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The drug cytochalasin B blocks the function of actin. Which of the following aspects of the animal cell cycle would be most disrupted by cytochalasin B?

Correct AnswerverifiedShow Answer

Which of the following characteristics would be most important for a chemotherapeutic drug designed to treat cancer cells?

Correct AnswerverifiedShow Answer

If all chromosomes are not attached to the mitotic spindle at the M phase checkpoint, the cells would most likely be arrested at which of the following points in the cell division cycle or mitosis?

Correct AnswerverifiedShow Answer

The drug cytochalasin B blocks the polymerization of actin microfilaments. Which of the following events of the cell cycle in animal cells would be most directly disrupted by cytochalasin B?

Correct AnswerverifiedShow Answer

After DNA replication, each duplicated chromosome consists of two of which of the following structures?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified