Question 1

Which eukaryotic DNA polymerase is thought to be the primary DNA-synthesizing enzyme during replication of the leading strand?

Accepted Answer

A) polymerase $\gamma$ 
B) polymerase $\delta$ 
C) polymerase $\varepsilon$ 
D) polymerase $\beta$ 
E) polymerase $\alpha$ 
A) polymerase $\gamma$ 
B) polymerase $\delta$ 
C) polymerase $\varepsilon$ 
D) polymerase $\beta$ 
E) polymerase $\alpha$ B

Question 2

Which DNA repair mechanism removes altered nucleotides generated by reactive chemicals present in the diet or produced by metabolism?

Accepted Answer

A) nucleotide excision repair 
B) base excision repair 
C) mismatch repair 
D) double-strand breakage repair 
E) the global genomic pathway 
A) nucleotide excision repair 
B) base excision repair 
C) mismatch repair 
D) double-strand breakage repair 
E) the global genomic pathway B

Question 3

Which type of DNA repair removes via a cut-and-patch mechanism a variety of bulky lesions,like pyrimidine dimers and nucleotides to which various chemical groups have been attached?

Accepted Answer

A) nucleotide excision repair 
B) base excision repair 
C) mismatch repair 
D) double-strand breakage repair 
E) All of these are correct. 
A) nucleotide excision repair 
B) base excision repair 
C) mismatch repair 
D) double-strand breakage repair 
E) All of these are correct. A

Question 4

What is the name of the noncatalytic component of the DNA polymerase III holoenzyme that keeps the polymerase associated with the DNA template?

Accepted Answer

A) $\beta$-pleated sheet 
B) $\alpha$-helix 
C) $\beta$ clamp 
D) $\alpha$ clamp 
E) $\gamma$ clamp 
A) $\beta$-pleated sheet 
B) $\alpha$-helix 
C) $\beta$ clamp 
D) $\alpha$ clamp 
E) $\gamma$ clamp

Question 5

In replicating bacterial chromosomes,where does replication terminate?

Accepted Answer

A) at the origin 
B) across the circular chromosome from the origin 
C) at random locations around the circle 
D) one quarter of the way around the DNA circle from the origin 
E) near Arnold 
A) at the origin 
B) across the circular chromosome from the origin 
C) at random locations around the circle 
D) one quarter of the way around the DNA circle from the origin 
E) near Arnold

Question 6

_________ are DNA unwinding enzymes that unwind the DNA in a reaction using the energy from ________ to move along one of the DNA strands,breaking the _______ holding the two strands together.

Accepted Answer

A) DNA helicases,ATP dehydration,disulfide linkages 
B) DNA gyrases,ATP hydrolysis,H bonds 
C) DNA helicases,ATP hydrolysis,3'-5'-phosphodiester linkages 
D) DNA helicases,ATP hydrolysis,H bonds 
E) DNA gyrases,ATP dehydration,H bonds 
A) DNA helicases,ATP dehydration,disulfide linkages 
B) DNA gyrases,ATP hydrolysis,H bonds 
C) DNA helicases,ATP hydrolysis,3'-5'-phosphodiester linkages 
D) DNA helicases,ATP hydrolysis,H bonds 
E) DNA gyrases,ATP dehydration,H bonds

Question 7

Who was the first to suggest semiconservative replication?

Accepted Answer

A) Meselson and Stahl 
B) Hershey and Chase 
C) Watson and Crick 
D) Avery,McCarty and MacLeod 
E) Darwin and Wallace 
A) Meselson and Stahl 
B) Hershey and Chase 
C) Watson and Crick 
D) Avery,McCarty and MacLeod 
E) Darwin and Wallace

Question 8

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what would the DNA look like if replication were dispersive?

Accepted Answer

A) All chromatids have one strand that contains BrdU and one strand that does not. 
B) All chromatids have two strands that contain BrdU. 
C) Half of the chromatids have two strands that contain BrdU and half of the chromatids have 2 strands lacking BrdU. 
D) Both strands of each chromatid contain mixtures of BrdU and thymidine. 
E) All chromatids lack BrdU. 
A) All chromatids have one strand that contains BrdU and one strand that does not. 
B) All chromatids have two strands that contain BrdU. 
C) Half of the chromatids have two strands that contain BrdU and half of the chromatids have 2 strands lacking BrdU. 
D) Both strands of each chromatid contain mixtures of BrdU and thymidine. 
E) All chromatids lack BrdU.

Question 9

Patients with the classical form of xeroderma pigmentosum have a defect in one of the genes involved in ______________.

Accepted Answer

A) nucleotide excision repair 
B) replication 
C) base excision repair 
D) transcription 
E) base excitation repair 
A) nucleotide excision repair 
B) replication 
C) base excision repair 
D) transcription 
E) base excitation repair

Question 10

The replication fork generates _______ supercoils in the _______ portion of the DNA molecule.

Accepted Answer

A) negative,replicated 
B) positive,replicated 
C) neutral,unreplicated 
D) positive,unreplicated 
E) negative,unreplicated 
A) negative,replicated 
B) positive,replicated 
C) neutral,unreplicated 
D) positive,unreplicated 
E) negative,unreplicated

Question 11

What supplies the energy that drives the relief of mechanical strain by DNA gyrase?

Accepted Answer

A) condensation of ATP 
B) condensation of GTP 
C) hydrolysis of ATP 
D) hydrolysis of GTP 
E) a proton gradient 
A) condensation of ATP 
B) condensation of GTP 
C) hydrolysis of ATP 
D) hydrolysis of GTP 
E) a proton gradient

Question 12

You are studying replication in a particular bacterial strain.At 37°C,the bacteria appear perfectly normal.If the temperature is raised to 43°C,however,they stop growing and are unable to replicate their DNA.If some of them are placed back at 37°C,they begin to replicate their DNA and are again perfectly normal.What is wrong?

Accepted Answer

The bacteria probably carry a

Question 13

What proteins bind selectively to single-stranded DNA and are responsible for keeping it extended and preventing it from being rewound?

Accepted Answer

A) DNA helicase 
B) DNA gyrase 
C) single-stranded DNA binding (SS
B) proteins 
D) ATPase 
E) DNA unwindase 
A) DNA helicase 
B) DNA gyrase 
C) single-stranded DNA binding (SS
B) proteins 
D) ATPase 
E) DNA unwindase

Question 14

A double-stranded breakage repair pathway that requires the presence of a second chromosome carrying the same sequence of genes as the damaged chromosome is called _________.

Accepted Answer

A) nonhomologous end joining repair 
B) homologous recombination 
C) NHEJ 
D) DNA methylation repair 
E) nonhomologous recombination 
A) nonhomologous end joining repair 
B) homologous recombination 
C) NHEJ 
D) DNA methylation repair 
E) nonhomologous recombination

Question 15

What is responsible for joining eukaryotic Okazaki fragments together?

Accepted Answer

A) DNA ligase 
B) DNA polymerase $\beta$ 
C) DNA polymerase  $\delta$ 
D) DNA polymerase $\varepsilon$ 
E) RNase H1 
A) DNA ligase 
B) DNA polymerase $\beta$ 
C) DNA polymerase  $\delta$ 
D) DNA polymerase $\varepsilon$ 
E) RNase H1

Question 16

How can the replication of both DNA strands by two tethered polymerases be accomplished when the template strands run in opposite directions?

Accepted Answer

A) One of the enzymes polymerizes DNA in the 3'->5' direction. 
B) The DNA of the lagging strand loops back on itself so it has same orientation as the leading strand template. 
C) The DNA of the leading strand loops back on itself so it has same orientation as the lagging strand template. 
D) The lagging strand is broken and then rejoined regularly to allow simultaneous synthesis. 
E) It just is. 
A) One of the enzymes polymerizes DNA in the 3'->5' direction. 
B) The DNA of the lagging strand loops back on itself so it has same orientation as the leading strand template. 
C) The DNA of the leading strand loops back on itself so it has same orientation as the lagging strand template. 
D) The lagging strand is broken and then rejoined regularly to allow simultaneous synthesis. 
E) It just is.

Question 17

The specific site on the bacterial chromosome at which replication begins is called the ________.

Accepted Answer

A) beginning 
B) origin 
C) initiation site 
D) initiator 
E) replicon 
A) beginning 
B) origin 
C) initiation site 
D) initiator 
E) replicon

Question 18

Which eukaryotic DNA polymerase replicates mitochondrial DNA and does not appear to be involved in nuclear DNA replication?

Accepted Answer

A) polymerase $\gamma$ 
B) polymerase  $\delta$ 
C) polymerase $\varepsilon$ 
D) polymerase $\beta$ 
E) polymerase $\alpha$ 
A) polymerase $\gamma$ 
B) polymerase  $\delta$ 
C) polymerase $\varepsilon$ 
D) polymerase $\beta$ 
E) polymerase $\alpha$

Question 19

Which DNA polymerase in bacteria is mostly involved in DNA repair to correct damaged DNA sections and removes RNA primers at the 5' ends of Okazaki fragments,replacing them with DNA?

Accepted Answer

A) DNA polymerase I 
B) DNA polymerase II 
C) DNA polymerase III 
D) DNA polymerase IV 
E) both DNA polymerase I and DNA polymerase III 
A) DNA polymerase I 
B) DNA polymerase II 
C) DNA polymerase III 
D) DNA polymerase IV 
E) both DNA polymerase I and DNA polymerase III

Question 20

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what does the DNA look like?

Accepted Answer

A) All chromatids have one strand that contains BrdU and one strand that contains thymidine. 
B) All chromatids have two strands that contain BrdU. 
C) Half of the chromatids have two strands that contain BrdU and half of the chromatids have 2 strands lacking BrdU. 
D) Both of the strands of each chromatid contain mixtures of BrdU and thymidine. 
E) All chromatids lack BrdU. 
A) All chromatids have one strand that contains BrdU and one strand that contains thymidine. 
B) All chromatids have two strands that contain BrdU. 
C) Half of the chromatids have two strands that contain BrdU and half of the chromatids have 2 strands lacking BrdU. 
D) Both of the strands of each chromatid contain mixtures of BrdU and thymidine. 
E) All chromatids lack BrdU.

Which eukaryotic DNA polymerase is thought to be the primary DNA-synthesizing enzyme during replication of the leading strand?

Which DNA repair mechanism removes altered nucleotides generated by reactive chemicals present in the diet or produced by metabolism?

Which type of DNA repair removes via a cut-and-patch mechanism a variety of bulky lesions,like pyrimidine dimers and nucleotides to which various chemical groups have been attached?

What is the name of the noncatalytic component of the DNA polymerase III holoenzyme that keeps the polymerase associated with the DNA template?

In replicating bacterial chromosomes,where does replication terminate?

___ are DNA unwinding enzymes that unwind the DNA in a reaction using the energy from to move along one of the DNA strands,breaking the _ holding the two strands together.

Who was the first to suggest semiconservative replication?

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what would the DNA look like if replication were dispersive?

Patients with the classical form of xeroderma pigmentosum have a defect in one of the genes involved in ______________.

The replication fork generates _ supercoils in the _ portion of the DNA molecule.

What supplies the energy that drives the relief of mechanical strain by DNA gyrase?

What proteins bind selectively to single-stranded DNA and are responsible for keeping it extended and preventing it from being rewound?

A double-stranded breakage repair pathway that requires the presence of a second chromosome carrying the same sequence of genes as the damaged chromosome is called _________.

What is responsible for joining eukaryotic Okazaki fragments together?

How can the replication of both DNA strands by two tethered polymerases be accomplished when the template strands run in opposite directions?

The specific site on the bacterial chromosome at which replication begins is called the ________.

Which eukaryotic DNA polymerase replicates mitochondrial DNA and does not appear to be involved in nuclear DNA replication?

Which DNA polymerase in bacteria is mostly involved in DNA repair to correct damaged DNA sections and removes RNA primers at the 5' ends of Okazaki fragments,replacing them with DNA?

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what does the DNA look like?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics,enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

Exam 13: Dna Replication and Repair

Which eukaryotic DNA polymerase is thought to be the primary DNA-synthesizing enzyme during replication of the leading strand?

Which DNA repair mechanism removes altered nucleotides generated by reactive chemicals present in the diet or produced by metabolism?

Which type of DNA repair removes via a cut-and-patch mechanism a variety of bulky lesions,like pyrimidine dimers and nucleotides to which various chemical groups have been attached?

What is the name of the noncatalytic component of the DNA polymerase III holoenzyme that keeps the polymerase associated with the DNA template?

In replicating bacterial chromosomes,where does replication terminate?

_________ are DNA unwinding enzymes that unwind the DNA in a reaction using the energy from ________ to move along one of the DNA strands,breaking the _______ holding the two strands together.

Who was the first to suggest semiconservative replication?

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what would the DNA look like if replication were dispersive?

Patients with the classical form of xeroderma pigmentosum have a defect in one of the genes involved in ______________.

The replication fork generates _______ supercoils in the _______ portion of the DNA molecule.

What supplies the energy that drives the relief of mechanical strain by DNA gyrase?

What proteins bind selectively to single-stranded DNA and are responsible for keeping it extended and preventing it from being rewound?

A double-stranded breakage repair pathway that requires the presence of a second chromosome carrying the same sequence of genes as the damaged chromosome is called _________.

What is responsible for joining eukaryotic Okazaki fragments together?

How can the replication of both DNA strands by two tethered polymerases be accomplished when the template strands run in opposite directions?

The specific site on the bacterial chromosome at which replication begins is called the ________.

Which eukaryotic DNA polymerase replicates mitochondrial DNA and does not appear to be involved in nuclear DNA replication?

Which DNA polymerase in bacteria is mostly involved in DNA repair to correct damaged DNA sections and removes RNA primers at the 5' ends of Okazaki fragments,replacing them with DNA?

Cultured mammalian cells grown in thymidine for many generations were allowed to undergo replication in the presence of bromodeoxyuridine (BrdU),which replaces thymidine in DNA.After one round of replication,what does the DNA look like?

Introduction to the Study of Cell and Molecular Biology

The Chemical Basis of Life

Bioenergetics,enzymes and Metabolism

The Structure and Function of the Plasma Membrane

Aerobic Respiration and the Mitochondrion

Photosynthesis and the Chloroplast

Interactions Between Cells and Their Environment

Cytoplasmic Membrane Systems: Structure, function, and Membrane Trafficking

The Cytoskeleton and Cell Motility

The Nature of the Gene and the Genome

Gene Expression: From Transcription to Translation

Control of Gene Expression

Cellular Reproduction

Cell Signaling and Signal Transduction: Communication Between Cells

Cancer

The Immune Response

Techniques in Cell and Molecular Biology

Filters

___ are DNA unwinding enzymes that unwind the DNA in a reaction using the energy from to move along one of the DNA strands,breaking the _ holding the two strands together.

The replication fork generates _ supercoils in the _ portion of the DNA molecule.