Question 1

Maturation promotion factor (MPF) , discovered by Masui and Markert, is the factor that

Accepted Answer

A)   is missing in the cdc2 mutant in yeast.
B)   induces entry into meiosis when injected into frog oocytes.
C)   fluctuates in amount during early cleavages of sea urchin eggs.
D)   fluctuates in amount during the cell cycle of mammalian cells.E) None of the above
F) C) and D)

Question 2

During G2, the Wee1 protein phosphorylates tyrosine-15 of the Cdc2 protein kinase, thus inactivating it. Only once dephosphorylation occurs and Cdc2 becomes active can the cell pass from G2 into M and proceed to cell division. Can you think of a reason why this protein was named Wee1?

Accepted Answer

G₂ is a period in the cell cycle during w...

Question 3

Cytokinesis begins during the _______ stage of mitosis.

Accepted Answer

The answer of Cytokinesis begins during the _______ stage of...

Question 4

Interphase is defined as

Accepted Answer

A)   the G1 and G2 phases.
B)   the G1, G2, and S phases.
C)   G0, the quiescent phase.
D)   M phase.E) C) and D)
F) All of the above

Question 5

The p21 and p15 proteins are examples of

Accepted Answer

A)   Cdk inhibitors.
B)   cyclins.
C)   oncogenes.
D)   growth factors.E) None of the above
F) B) and D)

Question 6

The most variable phase of the cell cycle is _______.

Accepted Answer

The answer of The most variable phase of the cell...

Question 7

A mutant cyclin B that is resistant to degradation by protease, but is otherwise active, would block the metaphase-to-anaphase transition.

Accepted Answer

A) True 
 B)False

Question 8

The passage of a cell through the stages of the cell cycle is controlled by protein kinases that phosphorylate many different proteins at appropriate times. What are these protein kinases called?

Accepted Answer

A)   Cdk activating kinases
B)   Cyclin-dependent kinases
C)   Cyclins
D)   Tyrosine kinasesE) A) and B)
F) A) and C)

Question 9

To prevent cells with unreplicated DNA from passing through the G2 checkpoint, Chk1 and Chk2 _______ protein phosphatase Cdc25.

Accepted Answer

A)   phosphorylate and stimulate
B)   phosphorylate and inhibit
C)   dephosphorylate and stimulate
D)   dephosphorylate and induce the degradation ofE) B) and D)
F) B) and C)

Question 10

Phosphorylation of the Golgi matrix proteins by Cdk1 during mitosis

Accepted Answer

A)   mediates breakdown of the Golgi apparatus into vesicles.
B)   activates proteins to degrade the Golgi proteins.
C)   inhibits association of the Golgi with microtubules.
D)   causes microtubules to pull the Golgi into two parts.E) None of the above
F) A) and D)

Question 11

Cells are restricted to one round of DNA replication per cycle by origin of replication binding proteins called

Accepted Answer

A)   ATMs.
B)   Akts.
C)   Oris.
D)   MCMs.E) All of the above
F) B) and C)

Question 12

Cell plate formation occurs only in _______ cells.

Accepted Answer

The answer of Cell plate formation occurs only in _______...

Question 13

Which of the following represents the amount of DNA in a typical G2 cell?

Accepted Answer

A)   n
B)   2n
C)   4n
D)   8nE) B) and D)
F) None of the above

Question 14

DNA content can be found using a method of flow cytometry that can determine 2n or 4n states of cells based on cell counting and fluorescent labeling of DNA. Which of the following phases would be identified through flow cytometry as 2n?

Accepted Answer

A)   G1 phase only
B)   S phase only
C)   G2 phase only
D)   Both G2 and M phasesE) A) and B)
F) A) and C)

Question 15

MPF is a general regulator of the transition from

Accepted Answer

A)   G1 to S.
B)   S to G2.
C)   G2 to M.
D)   metaphase to anaphase.E) B) and D)
F) A) and B)

Question 16

Progression through the cell cycle in the yeast Saccharomyces cerevisiae is regulated by

Accepted Answer

A)   external signals such as availability of nutrients and mating factors.
B)   internal signals such as growth factors and steroid hormones.
C)   internal signals such as the availability of glucose and ATP.
D)   simple organisms such as yeast do not have a cell cycle.E) All of the above
F) B) and C)

Question 17

MPF is a

Accepted Answer

A)   monomeric protein kinase.
B)   dimer of two molecules of Cdk1.
C)   dimer of Cdk1 and cyclin A.
D)   dimer of Cdk1 and cyclin B.E) B) and C)
F) All of the above

Question 18

During mitosis, the rate of microtubule turnover

Accepted Answer

A)   decreases.
B)   stays the same.
C)   doubles.
D)   increases five- to tenfold.E) B) and D)
F) A) and C)

Question 19

Separation of anaphase chromosomes begins when _______ is degraded to break the link between sister chromatids.

Accepted Answer

The answer of Separation of anaphase chromosomes begins when _______...

Question 20

Many cancer researchers and tumor biologists focus their studies on regulation of the cell cycle. Why?

Accepted Answer

When cancer begins to run unch...

Exam 18: The Cell Cycle

Interphase is defined as

Correct AnswerverifiedShow Answer

The passage of a cell through the stages of the cell cycle is controlled by protein kinases that phosphorylate many different proteins at appropriate times. What are these protein kinases called?

Correct AnswerverifiedShow Answer

To prevent cells with unreplicated DNA from passing through the G2 checkpoint, Chk1 and Chk2 _______ protein phosphatase Cdc25.

Correct AnswerverifiedShow Answer

Separation of anaphase chromosomes begins when _______ is degraded to break the link between sister chromatids.

Correct AnswerverifiedShow Answer

A mutant cyclin B that is resistant to degradation by protease, but is otherwise active, would block the metaphase-to-anaphase transition.

Correct AnswerverifiedShow Answer

MPF is a general regulator of the transition from

Correct AnswerverifiedShow Answer

The most variable phase of the cell cycle is _______.

Correct AnswerverifiedShow Answer

The p21 and p15 proteins are examples of

Correct AnswerverifiedShow Answer

Cytokinesis begins during the _______ stage of mitosis.

Correct AnswerverifiedShow Answer

Many cancer researchers and tumor biologists focus their studies on regulation of the cell cycle. Why?

Correct AnswerverifiedWhen cancer begins to run unch...View AnswerShow Answer

Cells are restricted to one round of DNA replication per cycle by origin of replication binding proteins called

Correct AnswerverifiedShow Answer

During mitosis, the rate of microtubule turnover

Correct AnswerverifiedShow Answer

During G2, the Wee1 protein phosphorylates tyrosine-15 of the Cdc2 protein kinase, thus inactivating it. Only once dephosphorylation occurs and Cdc2 becomes active can the cell pass from G2 into M and proceed to cell division. Can you think of a reason why this protein was named Wee1?

Correct AnswerverifiedG2 is a period in the cell cycle during w...View AnswerShow Answer

Maturation promotion factor (MPF) , discovered by Masui and Markert, is the factor that

Correct AnswerverifiedShow Answer

Progression through the cell cycle in the yeast Saccharomyces cerevisiae is regulated by

Correct AnswerverifiedShow Answer

Cell plate formation occurs only in _______ cells.

Correct AnswerverifiedShow Answer

Phosphorylation of the Golgi matrix proteins by Cdk1 during mitosis

Correct AnswerverifiedShow Answer

MPF is a

Correct AnswerverifiedShow Answer

Which of the following represents the amount of DNA in a typical G2 cell?

Correct AnswerverifiedShow Answer

DNA content can be found using a method of flow cytometry that can determine 2n or 4n states of cells based on cell counting and fluorescent labeling of DNA. Which of the following phases would be identified through flow cytometry as 2n?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

To prevent cells with unreplicated DNA from passing through the G₂ checkpoint, Chk1 and Chk2 _______ protein phosphatase Cdc25.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
When cancer begins to run unch...
View Answer

Correct Answer
verified

Correct Answer
verified

During G₂, the Wee1 protein phosphorylates tyrosine-15 of the Cdc2 protein kinase, thus inactivating it. Only once dephosphorylation occurs and Cdc2 becomes active can the cell pass from G₂ into M and proceed to cell division. Can you think of a reason why this protein was named Wee1?

Correct Answer
verified
G₂ is a period in the cell cycle during w...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Which of the following represents the amount of DNA in a typical G₂ cell?

Correct Answer
verified

Correct Answer
verified