Deck 35: DNA Repair and Recombination

Question 1

A photoreactivating enzyme is called ___________________.

Answer 1

DNA photolyase.

Question 2

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
An assay used to determine carcinogenic potential is the _______________ test.

Answer 2

d

Question 3

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is/are often found to cause alternative structures in DNA replication.

Answer 3

g

Question 4

Hydroxyl radicals cause DNA damage by ___________________.

Question 5

The human genetic skin disease that is caused by a mutation in components of the human nucleotide-excision-repair pathway is called ___________________.

Question 6

Proteins that contain a string of glutamines are likely to be involved in ___________________ disease.

Question 7

E coli DNA polymerase III removes mismatched nucleotides from the ___________________.

Question 8

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
A(n) _______________ chemically changes the nature of a base in DNA.

Question 9

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is the process for correcting for base-pair mismatches without excising bases.

Question 10

___________________ is the enzyme that converts polycyclic aromatic hydrocarbons into a reactive epoxide that alkylates the N-7 of guanine.

Question 11

Replication errors are often corrected by proofreading and ___________________.

Question 12

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is an enzyme that cleaves a glycosidic bond to release a damaged base.

Question 13

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is/are involved in joining DNA molecules together.

Question 14

X-rays cause damage to DNA by inducing ___________________.

Question 15

Light-driven DNA damage results in ___________________.

Question 16

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is/are caused by expanded trinucleotide repeats.

Question 17

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is/are typically involved in DNA repair.

Question 18

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
The enzyme that uses light energy to form an excited state to cleave the dimer into individual bases is _______________.

Question 19

___________________ are intermediates in recombination pathways composed of four polynucleotide chains in a cross-like structure.

Question 20

Use the following to answer questions
Choose the correct answer from the list below. Not all of the answers will be used.
a) uracil
b) DNA ligase
c) Huntington disease
d) Ames
e) xeroderma pigmentosum
f) tumor-suppressor genes
g) trinucleotide repeats
h) skin carcinoma
i) mutagen
j) direct repair
k) indirect repair
l) photolyase
_______________ is a rare skin disease caused by the inability to correct for UV damage to skin DNA.

Question 21

An important feature(s) of the Ames test is/are:

A) the inclusion of mammalian liver enzymes.
B) a linear response curve.
C) that the bacteria used are unable to grow in the absence of arginine.
D) A and B.
E) A, B and C.

Question 22

Describe the Ames test.

Question 23

Photolyase functions to:

A) repair pyrimidine dimers.
B) remove damaged bases.
C) ligate single-strand breaks.
D) All of the above.
E) None of the above.

Question 24

The three-strand structure involved in strand invasion is:

A) the D-loop.
B) recombinase DNA.
C) an RNA triplet.
D) non-Watson-Crick pairing.
E) RecA

Question 25

Name the types of DNA repair, categorized in groups.

Question 26

Why is thymine used in DNA instead of uracil?

Question 27

The process whereby two daughter molecules of DNA are formed by the exchange of genetic material between two parent molecules is known as:

A) chemical modification.
B) recombination.
C) alkylation.
D) dimerization.
E) None of the above.

Question 28

_________________ is an ATPase needed for DNA repair by recombination.

A) Polymerase III
B) RecA
C) RecB
D) RAD51
E) None of the above.

Question 29

How are breaks in DNA sealed that were formed during nucleotide-excision repair?

Question 30

Tumor-suppressor genes have a dominant negative genetic trait. What does this mean?

Question 31

Deamination of adenine causes what kind of mutations in DNA?

Question 32

Huntington disease is caused by:

A) pyrimidine dimers.
B) trinucleotide expansion.
C) suppressor mutants.
D) All of the above.
E) None of the above.

Question 33

In E. coli, mismatch repair involves:

A) recognition of mismatched pair by MutS.
B) removal of a mismatched nucleotide by DNA polymerase III.
C) cleavage of the backbone by MutH.
D) A and C
E) A, B, and C.

Question 34

Describe the consequences of incorrect DNA replication or DNA damage.

Question 35

Aflatoxin B1 is an example of a(n):

A) intercalating chemical.
B) alkylating agent.
C) base analog.
D) All of the above.
E) None of the above.

Question 36

Damage to DNA may result in:

A) cell death.
B) cell transformation.
C) changes in inherited sequences.
D) blockage of DNA replication.
E) All of the above.

Question 37

What are the enzymes needed for base-excision repair?

Question 38

Exposure to aflatoxin B1 can lead to:

A) the expansion of repeats of three nucleotides.
B) DNA damage by alkylation.
C) the defective repair of DNA.
D) the recombination of DNA.
E) None of the above.

Question 39

What are DNA adduct and how are they formed?

Question 40

Describe the difficulties in dealing with halts in DNA replication.

Question 41

Give examples of types of damage to DNA that have led to the development of a variety of DNA-repair systems.

Question 42

What does the phrase "recombination of genetic material" refer to?

Question 43

How do double-strand breaks occur during replication?

Question 44

How is recombination used as a biochemical tool?

Question 45

What role does the protein RAD51 play in recombination?