Question 1

pRb in cells undergoing differentiation will generally be

Accepted Answer

A) Unphosphorylated. 
B) Hyperphosphorylated. 
C) Bound to E2F transcription factors. 
D) Inactivated. 
E) Bound to histone acetylases. 
A) Unphosphorylated. 
B) Hyperphosphorylated. 
C) Bound to E2F transcription factors. 
D) Inactivated. 
E) Bound to histone acetylases. C

Question 2

When a cell is at G0,pRb is

Accepted Answer

A) Undetectable. 
B) Unphosphorylated. 
C) Hypophosphorylated. 
D) Hyperphosphorylated. 
E) Overexpressed. 
A) Undetectable. 
B) Unphosphorylated. 
C) Hypophosphorylated. 
D) Hyperphosphorylated. 
E) Overexpressed. B

Question 3

An increase in cyclin D activity may result from all of the following EXCEPT

Accepted Answer

A) Activation of the Ras signaling pathway. 
B) Activation of the Hedgehog signaling pathway. 
C) An increase in NF-κB expression. 
D) A decrease in STAT expression. 
E) A decrease in p16INK4A expression. 
A) Activation of the Ras signaling pathway. 
B) Activation of the Hedgehog signaling pathway. 
C) An increase in NF-κB expression. 
D) A decrease in STAT expression. 
E) A decrease in p16INK4A expression. D

Question 4

Which of the following scenarios may contribute to the hyperphosphorylation of pRb?

Accepted Answer

A) Inactivation of the Ras pathway 
B) Inactivation of p21Cip1 
C) Activation of p15INK4B 
D) Inactivation of NF-κB 
E) Activation of Smad3/4 
A) Inactivation of the Ras pathway 
B) Inactivation of p21Cip1 
C) Activation of p15INK4B 
D) Inactivation of NF-κB 
E) Activation of Smad3/4

Question 5

Which of the following types of mutations would NOT be advantageous to a cancer cell?

Accepted Answer

A) An inactivating mutation in pRb 
B) An inactivating mutation in a gene controlling a DNA damage checkpoint 
C) An inactivating mutation in p16INK4A 
D) An inactivating mutation in cyclin D 
E) An inactivating mutation in p19INK4D 
A) An inactivating mutation in pRb 
B) An inactivating mutation in a gene controlling a DNA damage checkpoint 
C) An inactivating mutation in p16INK4A 
D) An inactivating mutation in cyclin D 
E) An inactivating mutation in p19INK4D

Question 6

Which of the following types of mutations are MOST likely to be found in cancer cells?

Accepted Answer

A) Activating mutations in pRb 
B) Mutations resulting in deregulation of the restriction point 
C) Mutations resulting in enhanced restriction point regulation 
D) Mutations that promote differentiation 
E) C and D 
A) Activating mutations in pRb 
B) Mutations resulting in deregulation of the restriction point 
C) Mutations resulting in enhanced restriction point regulation 
D) Mutations that promote differentiation 
E) C and D

Question 7

Which of the following statements is NOT true of the pRb protein?

Accepted Answer

A) pRb is functionally inactive when it is hyperphosphorylated. 
B) pRb is mostly unphosphorylated during the G0 phase of the cell cycle. 
C) pRb is growth-promoting during early G1 phase. 
D) pRb phosphorylation is initiated by D-type cyclins and CDK4/6. 
E) pRb is functionally inactivated at the R point. 
A) pRb is functionally inactive when it is hyperphosphorylated. 
B) pRb is mostly unphosphorylated during the G0 phase of the cell cycle. 
C) pRb is growth-promoting during early G1 phase. 
D) pRb phosphorylation is initiated by D-type cyclins and CDK4/6. 
E) pRb is functionally inactivated at the R point.

Question 8

All of the following are true of the R point EXCEPT

Accepted Answer

A) It occurs at the G2/M transition. 
B) The cell's fate at this point may be influenced by growth factors in the cell's surroundings. 
C) Deregulation of signaling controlling the R point is common in cancer cells. 
D) It is followed by the activation of cyclin E/CDK2 complexes. 
E) Passage through this point is regulated by phosphorylation of pRb. 
A) It occurs at the G2/M transition. 
B) The cell's fate at this point may be influenced by growth factors in the cell's surroundings. 
C) Deregulation of signaling controlling the R point is common in cancer cells. 
D) It is followed by the activation of cyclin E/CDK2 complexes. 
E) Passage through this point is regulated by phosphorylation of pRb.

Question 9

Activation of Myc may result in all of the following EXCEPT

Accepted Answer

A) Hyperphosphorylation of pRb. 
B) Increased expression of CDK4. 
C) Degradation of p27Kip1. 
D) Increased transcription of target genes by E2F transcription factors. 
E) Decreased activation of cyclin E/CDK2 complexes. 
A) Hyperphosphorylation of pRb. 
B) Increased expression of CDK4. 
C) Degradation of p27Kip1. 
D) Increased transcription of target genes by E2F transcription factors. 
E) Decreased activation of cyclin E/CDK2 complexes.

Question 10

The resting,nonproliferative phase of the cell cycle is

Accepted Answer

A) G0. 
B) G1. 
C) G2. 
D) S. 
E) M. 
A) G0. 
B) G1. 
C) G2. 
D) S. 
E) M.

Question 11

Cyclin D/CDK4/6 complexes can be inhibited by

Accepted Answer

A) p27Kip1. 
B) p15INK4B. 
C) p57Kip2. 
D) p21Cip1. 
E) AP-1. 
A) p27Kip1. 
B) p15INK4B. 
C) p57Kip2. 
D) p21Cip1. 
E) AP-1.

Question 12

The critical decision point at which a cell determines its fate at the end of the G1 phase of the cell cycle is called

Accepted Answer

A) The transition point. 
B) The resolution point. 
C) The commitment point. 
D) The restriction point. 
E) The contraction point. 
A) The transition point. 
B) The resolution point. 
C) The commitment point. 
D) The restriction point. 
E) The contraction point.

Question 13

Histone deacetylase HDAC)enzymes

Accepted Answer

A) Promote initiation of transcription. 
B) Complex with hyperphosphorylated pRb. 
C) Repress E2F family activity. 
D) Add acetyl groups to E2F promoters. 
E) Promote initiation of translation. 
A) Promote initiation of transcription. 
B) Complex with hyperphosphorylated pRb. 
C) Repress E2F family activity. 
D) Add acetyl groups to E2F promoters. 
E) Promote initiation of translation.

Question 14

Which of the following may result from activation of TGF-β?

Accepted Answer

A) Increased activation of cyclin D/CDK4/6 complexes 
B) Increased expression of p21Cip1 in the cytoplasm of the cell 
C) Reduced expression of p15INK4B 
D) Decreased activation of cyclin E/CDK2 complexes 
E) Phosphorylation of Smad4 
A) Increased activation of cyclin D/CDK4/6 complexes 
B) Increased expression of p21Cip1 in the cytoplasm of the cell 
C) Reduced expression of p15INK4B 
D) Decreased activation of cyclin E/CDK2 complexes 
E) Phosphorylation of Smad4

Question 15

In a normal cell,signals from the external environment play a role in determining whether the cell will grow or replicate during what phases)of the cell cycle?

Accepted Answer

A) The S phase only 
B) The G1 phase only 
C) The G2 phase only 
D) Both the G2 and S phases 
E) All phases of the cell cycle 
A) The S phase only 
B) The G1 phase only 
C) The G2 phase only 
D) Both the G2 and S phases 
E) All phases of the cell cycle

Question 16

Levels of cyclin A are highest during the phase of the cell cycle in which

Accepted Answer

A) The cell prepares to enter a quiescent state. 
B) Mitosis occurs. 
C) The cell is most responsive to mitogenic growth factors. 
D) Cytokinesis occurs. 
E) DNA replication occurs. 
A) The cell prepares to enter a quiescent state. 
B) Mitosis occurs. 
C) The cell is most responsive to mitogenic growth factors. 
D) Cytokinesis occurs. 
E) DNA replication occurs.

Question 17

The cyclin/cyclin-dependent kinase pair that is active during the M phase of the cell cycle is

Accepted Answer

A) Cyclin A/CDC2. 
B) Cyclin B/CDC2. 
C) Cyclin D/CDK4/6. 
D) Cyclin E/CDK2. 
E) Cyclin A/CDK2. 
A) Cyclin A/CDC2. 
B) Cyclin B/CDC2. 
C) Cyclin D/CDK4/6. 
D) Cyclin E/CDK2. 
E) Cyclin A/CDK2.

pRb in cells undergoing differentiation will generally be

When a cell is at G₀,pRb is

An increase in cyclin D activity may result from all of the following EXCEPT

Which of the following scenarios may contribute to the hyperphosphorylation of pRb?

Which of the following types of mutations would NOT be advantageous to a cancer cell?

Which of the following types of mutations are MOST likely to be found in cancer cells?

Which of the following statements is NOT true of the pRb protein?

All of the following are true of the R point EXCEPT

Activation of Myc may result in all of the following EXCEPT

The resting,nonproliferative phase of the cell cycle is

Cyclin D/CDK4/6 complexes can be inhibited by

The critical decision point at which a cell determines its fate at the end of the G₁ phase of the cell cycle is called

Histone deacetylase HDAC)enzymes

Which of the following may result from activation of TGF-β?

In a normal cell,signals from the external environment play a role in determining whether the cell will grow or replicate during what phases)of the cell cycle?

Levels of cyclin A are highest during the phase of the cell cycle in which

The cyclin/cyclin-dependent kinase pair that is active during the M phase of the cell cycle is

The Biology and Genetics of Cells and Organisms

The Nature of Cancer

Tumor Viruses

Cellular Oncogenes

Growth Factors,receptors,and Cancer

Cytoplasmic Signaling Circuitry Programs Many of the Traits of Cancer

Tumor Suppressor Genes

P53 and Apoptosis: Master Guardian and Executioner

Eternal Life: Cell Immortalization and Tumorigenesis

Multi-Step Tumorigenesis

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Dialogue Replaces Monologue: Heterotypic Interactions and the Biology of Angiogenesis

Moving Out: Invasion and Metastasis

Crowd Control: Tumor Immunology and Immunotherapy

The Rational Treatment of Cancer

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Exam 8: Prb and Control of the Cell Cycle Clock

pRb in cells undergoing differentiation will generally be

When a cell is at G0,pRb is

An increase in cyclin D activity may result from all of the following EXCEPT

Which of the following scenarios may contribute to the hyperphosphorylation of pRb?

Which of the following types of mutations would NOT be advantageous to a cancer cell?

Which of the following types of mutations are MOST likely to be found in cancer cells?

Which of the following statements is NOT true of the pRb protein?

All of the following are true of the R point EXCEPT

Activation of Myc may result in all of the following EXCEPT

The resting,nonproliferative phase of the cell cycle is

Cyclin D/CDK4/6 complexes can be inhibited by

The critical decision point at which a cell determines its fate at the end of the G1 phase of the cell cycle is called

Histone deacetylase HDAC)enzymes

Which of the following may result from activation of TGF-β?

In a normal cell,signals from the external environment play a role in determining whether the cell will grow or replicate during what phases)of the cell cycle?

Levels of cyclin A are highest during the phase of the cell cycle in which

The cyclin/cyclin-dependent kinase pair that is active during the M phase of the cell cycle is

The Biology and Genetics of Cells and Organisms

The Nature of Cancer

Tumor Viruses

Cellular Oncogenes

Growth Factors,receptors,and Cancer

Cytoplasmic Signaling Circuitry Programs Many of the Traits of Cancer

Tumor Suppressor Genes

P53 and Apoptosis: Master Guardian and Executioner

Eternal Life: Cell Immortalization and Tumorigenesis

Multi-Step Tumorigenesis

Maintenance of Genomic Integrity and the Development of Cancer

Dialogue Replaces Monologue: Heterotypic Interactions and the Biology of Angiogenesis

Moving Out: Invasion and Metastasis

Crowd Control: Tumor Immunology and Immunotherapy

The Rational Treatment of Cancer

Filters

When a cell is at G₀,pRb is

The critical decision point at which a cell determines its fate at the end of the G₁ phase of the cell cycle is called