Question 1

What are oncogenes and tumor-suppressor genes? How are they involved in carcinogenesis?

Accepted Answer

The control of the cell division cycle i...

Question 2

How can defects in DNA-repair mechanisms lead to the development of cancer?

Accepted Answer

Defects in DNA-repair mechanis...

Question 3

Deletions of what categories of genes are likely lead to cancer?

Accepted Answer

A)  Tumor suppressors
B)  Proto-oncogenes
C)  Growth factors
D)  All of the answers are correct.
E)  None of the answers is correct.F) B) and C)
G) A) and B)

Question 4

Retinoblastoma (RB)protein is important in regulating the cell cycle.It must be completely phosphorylated before the cell can move from the G1 to the S phase of the cell cycle.Retinoblastoma is a type of cancer.Based on this information, what do you think goes wrong in retinoblastoma?

Accepted Answer

Retinoblastoma is one example of several...

Question 5

In Burkitt lymphoma, there is increased expression of the MYC gene.Which of the following BEST explains this situation?

Accepted Answer

A)  A chromosome deletion has removed a tumor-suppressor gene.
B)  A chromosome deletion has removed an oncogene.
C)  There is a chromosome duplication that involves a segment with an oncogene.
D)  A translocation has brought the MYC gene next to a different regulatory region.
E)  The MYC gene has been amplified.F) C) and D)
G) D) and E)

Question 6

The increased levels of telomerase associated with many tumor cells likely promotes cancer by:

Accepted Answer

A)  enhancing levels of DNA repair so that cells remain normal and have stable genomes and thus would be able to replicate their DNA and divide more often.
B)  promoting the efficiency of the spindle-assembly checkpoint.
C)  reducing the expression of several oncogenes.
D)  allowing cells to continue to divide when, normally, chromosomes should shorten beyond a point where division would be no longer possible.
E)  decreasing the number of epigenetic changes that would promote cancer.F) A) and B)
G) B) and D)

Question 7

The Philadelphia chromosome is:

Accepted Answer

A)  an example of an aneuploidy.
B)  the result of a translocated chromosome involving parts of chromosomes 9 and 22.
C)  a lengthened version of chromosome 22 that results from a recombination event with chromosome 12.
D)  a shortened version of chromosome 22 that results from a deletion.
E)  a lengthened version of chromosome 22 that results from a duplication.F) All of the above
G) A) and B)

Question 8

List three ways in which proto-oncogenes can be converted to oncogenes by viruses.

Accepted Answer

(1)The sequence of the proto-oncogene ma...

Question 9

What kind of enzyme phosphorylates other proteins, in turn either activating or inactivating the protein?

Accepted Answer

A)  Cyclin
B)  Cyclin-dependent kinases
C)  Telomerase
D)  GTPase
E)  DNA polymeraseF) None of the above
G) A) and E)

Question 10

Explain how DNA sequencing studies can aid in our understanding of cancer formation.

Accepted Answer

DNA sequencing technology has been used ...

Question 11

Which of the following types of cancer is associated with a defect in nucleotide-excision repair?

Accepted Answer

A)  Retinoblastoma
B)  Xeroderma pigmentosum
C)  Cervical cancer
D)  Chronic myelogenous leukemia
E)  Bloom syndromeF) A) and B)
G) B) and C)

Question 12

Which of the following statements is TRUE concerning the function of proto-oncogenes?

Accepted Answer

A)  They make products that act as signals to initiate cellular apoptosis.
B)  Their products are components of cell growth.
C)  Proto-oncogenes make products that act as cell checkpoint regulators.
D)  Proto-oncogenes make products that scan the genome for DNA damage.
E)  Proto-oncogenes make products that repair DNA at sites of lesions.F) A) and B)
G) A) and E)

Question 13

Which of the following BEST characterizes many cancers such as colorectal cancer?

Accepted Answer

A)  They result from the activation of one critical tumor-suppressor gene.
B)  They result when the transition from G2 to M in the cell cycle is inhibited.
C)  They result when DNA replication during the S period of the cell cycle is inhibited.
D)  They result from a series of sequential mutations in a number of genes.
E)  They result from decreased expression in a series of cellular oncogenes.F) A) and E)
G) B) and E)

Question 14

Many viruses that are associated with cancers in animals are _____ that use reverse transcriptase.

Accepted Answer

A)  papilloma viruses
B)  Epstein-Barr virus
C)  retroviruses
D)  hepatitis B virus
E)  None of the answers is correct.F) A) and E)
G) B) and E)

Question 15

Explain briefly why changes in oncogenes result in more rapid progression of a cancer compared to changes in tumor-suppressor genes.Mention one situation in which changes in a tumor-suppressor gene have a similar likelihood of causing cancer as changes in an oncogene.

Accepted Answer

A single mutation in DNA is sufficient t...

Question 16

Briefly describe the relationship among cyclins, cyclin-dependent kinases (CDKs), and cancer.

Accepted Answer

Cyclins and CDKs play critical roles in ...

Question 17

The development of colorectal cancer is relatively well understood.Describe the steps of the development of colorectal cancer, including any genetic components.

Accepted Answer

There can be a genetic basis to colon ca...

Question 18

How do we know that cancer is a genetic disease?

Accepted Answer

A)  For all individuals that carry a cancer gene, cancer will develop in every tissue in the body.
B)  Cancer is a leading cause of mortality worldwide.
C)  Only cells exposed to chemical mutagens, but not ionizing radiation, will develop cancer.
D)  Certain types of cancer often share the same chromosomal abnormalities.
E)  All of the answers are correct.F) B) and E)
G) A) and B)

Question 19

Which of the following is NOT correct?

Accepted Answer

A)  Mutations in oncogenes often act in a dominant manner.
B)  Mutations in tumor-suppressor genes often act in a recessive manner.
C)  In cancer, tumor-suppressor genes often convert to oncogenes following exposure to mutagens.
D)  Normal action of proto-oncogenes is to stimulate cell proliferation.
E)  All of the answers are correct.F) A) and D)
G) All of the above

Question 20

Which of the following occurs in familial retinoblastoma?

Accepted Answer

A)  There are two subsequent gametic mutations in Retinoblastoma (Rb) gene.
B)  A single mutation in the Retinoblastoma (Rb) gene leads to the loss of heterozygosity.
C)  Tumors develop only after exposure to ionizing radiation.
D)  Changes in the cytoskeleton lead to mutations in the Retinoblastoma (Rb) gene.
E)  Multiple gametic cells mutate all at once.F) B) and D)
G) All of the above

Exam 16: Cancer Genetics

The development of colorectal cancer is relatively well understood.Describe the steps of the development of colorectal cancer, including any genetic components.

Correct AnswerverifiedThere can be a genetic basis to colon ca...View AnswerShow Answer

Which of the following types of cancer is associated with a defect in nucleotide-excision repair?

Correct AnswerverifiedShow Answer

What kind of enzyme phosphorylates other proteins, in turn either activating or inactivating the protein?

Correct AnswerverifiedShow Answer

List three ways in which proto-oncogenes can be converted to oncogenes by viruses.

Correct Answerverified(1)The sequence of the proto-oncogene ma...View AnswerShow Answer

Retinoblastoma (RB)protein is important in regulating the cell cycle.It must be completely phosphorylated before the cell can move from the G1 to the S phase of the cell cycle.Retinoblastoma is a type of cancer.Based on this information, what do you think goes wrong in retinoblastoma?

Correct AnswerverifiedRetinoblastoma is one example of several...View AnswerShow Answer

How do we know that cancer is a genetic disease?

Correct AnswerverifiedShow Answer

In Burkitt lymphoma, there is increased expression of the MYC gene.Which of the following BEST explains this situation?

Correct AnswerverifiedShow Answer

Explain how DNA sequencing studies can aid in our understanding of cancer formation.

Correct AnswerverifiedDNA sequencing technology has been used ...View AnswerShow Answer

Explain briefly why changes in oncogenes result in more rapid progression of a cancer compared to changes in tumor-suppressor genes.Mention one situation in which changes in a tumor-suppressor gene have a similar likelihood of causing cancer as changes in an oncogene.

Correct AnswerverifiedA single mutation in DNA is sufficient t...View AnswerShow Answer

Many viruses that are associated with cancers in animals are _____ that use reverse transcriptase.

Correct AnswerverifiedShow Answer

The increased levels of telomerase associated with many tumor cells likely promotes cancer by:

Correct AnswerverifiedShow Answer

What are oncogenes and tumor-suppressor genes? How are they involved in carcinogenesis?

Correct AnswerverifiedThe control of the cell division cycle i...View AnswerShow Answer

How can defects in DNA-repair mechanisms lead to the development of cancer?

Correct AnswerverifiedDefects in DNA-repair mechanis...View AnswerShow Answer

Which of the following BEST characterizes many cancers such as colorectal cancer?

Correct AnswerverifiedShow Answer

Briefly describe the relationship among cyclins, cyclin-dependent kinases (CDKs), and cancer.

Correct AnswerverifiedCyclins and CDKs play critical roles in ...View AnswerShow Answer

Which of the following statements is TRUE concerning the function of proto-oncogenes?

Correct AnswerverifiedShow Answer

Which of the following occurs in familial retinoblastoma?

Correct AnswerverifiedShow Answer

Which of the following is NOT correct?

Correct AnswerverifiedShow Answer

The Philadelphia chromosome is:

Correct AnswerverifiedShow Answer

Deletions of what categories of genes are likely lead to cancer?

Correct AnswerverifiedShow Answer

Correct Answer
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There can be a genetic basis to colon ca...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
(1)The sequence of the proto-oncogene ma...
View Answer

Correct Answer
verified
Retinoblastoma is one example of several...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
DNA sequencing technology has been used ...
View Answer

Correct Answer
verified
A single mutation in DNA is sufficient t...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The control of the cell division cycle i...
View Answer

Correct Answer
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Defects in DNA-repair mechanis...
View Answer

Correct Answer
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Correct Answer
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Cyclins and CDKs play critical roles in ...
View Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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