Question 1

Which of the following describes the usefulness of primase?

Accepted Answer

A) It removes RNA bases and replaces them with DNA bases. 
B) It seals nicks. 
C) It adds an RNA starter sequence which can be elongated. 
D) It is only required on the leading strand. 
E) It unwinds the DNA. 
A) It removes RNA bases and replaces them with DNA bases. 
B) It seals nicks. 
C) It adds an RNA starter sequence which can be elongated. 
D) It is only required on the leading strand. 
E) It unwinds the DNA.

Question 2

A prokaryotic replisome typically contains two molecules of DNA pol III, but only one molecule of DNA pol I.Why?

Accepted Answer

A) The DNA pol I works on the leading strand, while DNA pol IIIs work on the Okazaki fragments.since there are several of those, it takes more proteins to keep up. 
B) DNA pol I has a built-in proofreading exonuclease; DNA pol III does not.The second DNA pol III is needed to follow the first to accomplish the necessary proofreading. 
C) The DNA pol IIIs work at one replication fork, while the DNA pol I works at the other.This way they don't meet exactly at the other side of the chromosome. 
D) The DNA pol IIIs do most of the work.DNA pol I only has to work on the telomers. 
E) DNA pol I replaces the RNA primers with DNA, which really only needs to be done repetitively on one strand, while both strands are worked on by the DNA pol IIIs. 
A) The DNA pol I works on the leading strand, while DNA pol IIIs work on the Okazaki fragments.since there are several of those, it takes more proteins to keep up. 
B) DNA pol I has a built-in proofreading exonuclease; DNA pol III does not.The second DNA pol III is needed to follow the first to accomplish the necessary proofreading. 
C) The DNA pol IIIs work at one replication fork, while the DNA pol I works at the other.This way they don't meet exactly at the other side of the chromosome. 
D) The DNA pol IIIs do most of the work.DNA pol I only has to work on the telomers. 
E) DNA pol I replaces the RNA primers with DNA, which really only needs to be done repetitively on one strand, while both strands are worked on by the DNA pol IIIs.

Question 3

Which of the following statements about the fidelity of replication is FALSE?

Accepted Answer

A) Cells maintaining an equal concentration of each dNTP helps maintain fidelity. 
B) DNA polymerase catalyzes synthesis in a two-stage reaction, ensuring the proper base is added. 
C) Cells viability is removed when DNA point mutations are incorporated. 
D) Pol I and Pol III are both involved in increasing fidelity. 
E) Specific repair systems repair and maintain DNA. 
A) Cells maintaining an equal concentration of each dNTP helps maintain fidelity. 
B) DNA polymerase catalyzes synthesis in a two-stage reaction, ensuring the proper base is added. 
C) Cells viability is removed when DNA point mutations are incorporated. 
D) Pol I and Pol III are both involved in increasing fidelity. 
E) Specific repair systems repair and maintain DNA.

Question 4

Lagging stands are polymerized in the ______ direction, and the DNA fragments are about ______ nucleotides (nt)long in eukaryotic cells.

Accepted Answer

A) 5' to 3'0, 100-200 
B) 5' to 3', 1000-2000 
C) 3' to 5', 100-400 
D) 3' to 5', 1000-50000 
E) none of the above 
A) 5' to 3'0, 100-200 
B) 5' to 3', 1000-2000 
C) 3' to 5', 100-400 
D) 3' to 5', 1000-50000 
E) none of the above

Question 5

Use the following information to answer the next questions :
Suppose that an error in replication occurred at position 324 in the E.coli sequence below, and that a GATC motif used to regulate replication and restriction is located about 300 bp away.Note that the A on the bottom (shown by the underlining)strand is methylated.
 
-What enzymes would be used to repair this error?

Accepted Answer

A) methyl-directed mismatch repair enzymes 
B) nucleotide excision repair enzymes 
C) methyl-directed double strand break repair enzymes 
D) UvrABC plus UvrD 
E) None of the above systems can repair this error 
A) methyl-directed mismatch repair enzymes 
B) nucleotide excision repair enzymes 
C) methyl-directed double strand break repair enzymes 
D) UvrABC plus UvrD 
E) None of the above systems can repair this error

Question 6

Suppose Meselson & Stahl had observed the following data in their famous experiment involving a switch from medium containing 15N to 14N.What would they have concluded about the nature of DNA replication?

Accepted Answer

A) They still would have concluded that DNA replication is semiconservative. 
B) They would have concluded that DNA replication is conservative. 
C) They would have concluded that DNA replication is dispersive/random. 
D) None of the above is correct. 
E) Cannot be determined with the information given. 
A) They still would have concluded that DNA replication is semiconservative. 
B) They would have concluded that DNA replication is conservative. 
C) They would have concluded that DNA replication is dispersive/random. 
D) None of the above is correct. 
E) Cannot be determined with the information given.

Question 7

Use the following diagram to complete the sentences below   " ______ is the enzyme which catalyzes phosphodiester bond formation on both strands.Processivity of DNA pol is increased when associated with ____.DNA untwisting is accomplished by ______."

Accepted Answer

A) A, C, B 
B) A, B, C 
C) B, C, A 
D) A, D, B 
E) A, E, B 
A) A, C, B 
B) A, B, C 
C) B, C, A 
D) A, D, B 
E) A, E, B

Question 8

When a section of DNA is damaged and polymerization cannot proceed, _____ repair can reconstitute the damaged replication fork.

Accepted Answer

A) mismatch 
B) nucleotide excision 
C) recombination 
D) photoreactivation 
E) base excision 
A) mismatch 
B) nucleotide excision 
C) recombination 
D) photoreactivation 
E) base excision

Question 9

Matching 
Choose the correct answer from the list. Not all the answers will be used.
-G-rich polynucleotides can form _______

Accepted Answer

A) SSB 
B) Tus 
C) primosome 
D) ARS 
E) ATS
F)primer
G)transposons
H)nick translation
I)photolyase
J)processive
K)G-loops
L)G-quartets
M)accurate
N)lagging strand synthesis
O)MCM
P)abortive 
A) SSB 
B) Tus 
C) primosome 
D) ARS 
E) ATS
F)primer
G)transposons
H)nick translation
I)photolyase
J)processive
K)G-loops
L)G-quartets
M)accurate
N)lagging strand synthesis
O)MCM
P)abortive

Question 10

Use the following information to answer the next questions :
Suppose that an error in replication occurred at position 324 in the E.coli sequence below, and that a GATC motif used to regulate replication and restriction is located about 300 bp away.Note that the A on the bottom (shown by the underlining)strand is methylated.
 
-E.coli DNA repair enzymes act on the sequence.Which of the following will result?

Accepted Answer

A) The underlined A will be changed to a C. 
B) The underlined G will be changed to a T. 
C) The underlined A will be methylated. 
D) The underlined G will be methylated. 
E) More than one of the above is correct 
A) The underlined A will be changed to a C. 
B) The underlined G will be changed to a T. 
C) The underlined A will be methylated. 
D) The underlined G will be methylated. 
E) More than one of the above is correct

Which of the following describes the usefulness of primase?

A prokaryotic replisome typically contains two molecules of DNA pol III, but only one molecule of DNA pol I.Why?

Which of the following statements about the fidelity of replication is FALSE?

Lagging stands are polymerized in the direction, and the DNA fragments are about nucleotides (nt)long in eukaryotic cells.

Suppose Meselson & Stahl had observed the following data in their famous experiment involving a switch from medium containing 15N to 14N.What would they have concluded about the nature of DNA replication?

Use the following diagram to complete the sentences below " is the enzyme which catalyzes phosphodiester bond formation on both strands.Processivity of DNA pol is increased when associated with .DNA untwisting is accomplished by ."

When a section of DNA is damaged and polymerization cannot proceed, _____ repair can reconstitute the damaged replication fork.

Matching Choose the correct answer from the list. Not all the answers will be used. -G-rich polynucleotides can form _______

Introduction to the Chemistry of Life

Water

Nucleotides, Nucleic Acids, and Genetic Information

Amino Acids

Proteins: Primary Structure

Proteins: Three-Dimensional Structure

Protein Function Part I: Myoglobin and Hemoglobin

Carbohydrates

Lipids and Biological Membranes

Membrane Transport

Enzyme Catalysis

Enzyme Kinetics, Inhibition and Control

Biochemical Signaling

Introduction to Metabolism

Glycogen Metabolism and Gluconeogenesis

Glucose Catabolism

Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Mammalian Fuel Metabolism: Integration and Regulation

Nucleotide Metabolism

Nucleic Acid Structure

Transcription and Rna Processing

Translation

Regulation of Gene Expression

Filters

Exam 25: Dna Replication, Repair and Recombination

Which of the following describes the usefulness of primase?

A prokaryotic replisome typically contains two molecules of DNA pol III, but only one molecule of DNA pol I.Why?

Which of the following statements about the fidelity of replication is FALSE?

Lagging stands are polymerized in the ______ direction, and the DNA fragments are about ______ nucleotides (nt)long in eukaryotic cells.

Suppose Meselson & Stahl had observed the following data in their famous experiment involving a switch from medium containing 15N to 14N.What would they have concluded about the nature of DNA replication?

Use the following diagram to complete the sentences below " ______ is the enzyme which catalyzes phosphodiester bond formation on both strands.Processivity of DNA pol is increased when associated with ____.DNA untwisting is accomplished by ______."

When a section of DNA is damaged and polymerization cannot proceed, _____ repair can reconstitute the damaged replication fork.

Matching Choose the correct answer from the list. Not all the answers will be used. -G-rich polynucleotides can form _______

Introduction to the Chemistry of Life

Water

Nucleotides, Nucleic Acids, and Genetic Information

Amino Acids

Proteins: Primary Structure

Proteins: Three-Dimensional Structure

Protein Function Part I: Myoglobin and Hemoglobin

Carbohydrates

Lipids and Biological Membranes

Membrane Transport

Enzyme Catalysis

Enzyme Kinetics, Inhibition and Control

Biochemical Signaling

Introduction to Metabolism

Glycogen Metabolism and Gluconeogenesis

Glucose Catabolism

Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Mammalian Fuel Metabolism: Integration and Regulation

Nucleotide Metabolism

Nucleic Acid Structure

Transcription and Rna Processing

Translation

Regulation of Gene Expression

Filters

Lagging stands are polymerized in the direction, and the DNA fragments are about nucleotides (nt)long in eukaryotic cells.

Use the following diagram to complete the sentences below " is the enzyme which catalyzes phosphodiester bond formation on both strands.Processivity of DNA pol is increased when associated with .DNA untwisting is accomplished by ."