Question 1

Meselson and Stahl used heavy nitrogen (15N) in their experiments to

Accepted Answer

A)  provide a primer. 
B)  assist the DNA polymerase. 
C)  label the original DNA. 
D)  enable discrimination of density gradient. 
E)  be used as an energy source. 
A)  provide a primer. 
B)  assist the DNA polymerase. 
C)  label the original DNA. 
D)  enable discrimination of density gradient. 
E)  be used as an energy source. C

Question 2

The molecules that function to replicate DNA in the cell are

Accepted Answer

A)  DNA nucleoside triphosphates. 
B)  DNA polymerases. 
C)  nucleoside polymerases. 
D)  DNases. 
E)  ribonucleases. 
A)  DNA nucleoside triphosphates. 
B)  DNA polymerases. 
C)  nucleoside polymerases. 
D)  DNases. 
E)  ribonucleases. B

Question 3

Mutations are

Accepted Answer

A)  permanent changes in DNA. 
B)  changes in the phosphate backbone of DNA. 
C)  mistakes in the incorporation of amino acids into proteins. 
D)  changes in the mRNA of an organism. 
E)  always harmful. 
A)  permanent changes in DNA. 
B)  changes in the phosphate backbone of DNA. 
C)  mistakes in the incorporation of amino acids into proteins. 
D)  changes in the mRNA of an organism. 
E)  always harmful. A

Question 4

If a G-T base pair is found in a newly replicated DNA molecule after proofreading, the _______ repair mechanism might replace the G with an A.

Accepted Answer

The answer of If a G-T base pair is found...

Question 5

Before Watson and Crick built their DNA model, the American chemist and Nobel laureate Linus Pauling proposed a triple-helix model for DNA.What evidence convinced Watson and Crick to reject this model for the double-helix model?

Accepted Answer

A)  Franklin's X-ray crystallography 
B)  Chargaff's observations of base pairing 
C)  Avery's studies of DNA as the transforming agent 
D)  The Hershey and Chase blender experiment 
E)  Studies examining the stability of DNA 
A)  Franklin's X-ray crystallography 
B)  Chargaff's observations of base pairing 
C)  Avery's studies of DNA as the transforming agent 
D)  The Hershey and Chase blender experiment 
E)  Studies examining the stability of DNA

Question 6

If the proportion of C in a double-stranded DNA molecule is x, what is the proportion of T?

Accepted Answer

A)  x 
B)  x/2 
C)  1 F1F1F1S1F1F1F10 x 
D)  ½ F1F1F1S1F1F1F10 x 
E)  2x 
A)  x 
B)  x/2 
C)  1 F1F1F1S1F1F1F10 x 
D)  ½ F1F1F1S1F1F1F10 x 
E)  2x

Question 7

What structural aspect of the DNA facilitates dissociation of the two DNA strands for replication?
a. Purine-pyrimidine pairing
b. Hydrogen bonding between paired bases
c. Covalent bonds between sugars and phosphate groups
d. 3F1F1F1S1F1F1F10 end phosphorylation
e. Antiparallel DNA strands

Accepted Answer

The answer of What structural aspect of the DNA facilitates...

Question 8

Which material serves as the template in DNA synthesis?

Accepted Answer

A)  Deoxyribonucleoside triphosphates 
B)  DNA polymerase 
C)  A DNA strand 
D)  A salt buffer 
E)  The primer 
A)  Deoxyribonucleoside triphosphates 
B)  DNA polymerase 
C)  A DNA strand 
D)  A salt buffer 
E)  The primer

Question 9

An automated process that makes multiple copies of short regions of DNA in a test tube is called _______.

Accepted Answer

polymerase

Question 10

Refer to the figure, which shows double-stranded DNA being prepared for DNA replication.   What proteins (not shown) act on the DNA to unwind and dissociate the strands, and what proteins (not shown) keep the template strands separated?

Accepted Answer

DNA helicase unwinds the doubl

Question 11

Refer to the chemical formula of dideoxycytidine.   The drug dideoxycytidine, used to treat certain viral infections, is a nucleotide made with 2F1F1F1S1F1F1F10,3F1F1F1S1F1F1F10-dideoxyribose.This sugar lacks -OH groups at both the 2F1F1F1S1F1F1F10 and the 3F1F1F1S1F1F1F10 positions.What will happen if this nucleotide is incorporated into a growing DNA chain?

Accepted Answer

DNA replication adds new nucleotides to

Question 12

Refer to the figure.   Which letter refers to an Okazaki fragment?

Accepted Answer

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

Question 13

If a sequence of one strand of DNA is 5ʹ-ATGATGT-3ʹ, the complementary strand must be _______.(Include correct orientation.)

Accepted Answer

The answer of If a sequence of one strand of...

Question 14

The nucleoside analogue acyclovir, which is used to treat herpes simplex virus (HSV) infections, lacks a 3F1F1F1S1F1F1F10 hydroxyl group (-OH).Predict what will happen if the host cell DNA polymerase incorporates a molecule of acyclovir into an elongating strand of HSV DNA.
a. Acyclovir will block the activity of the DNA helicase.
b. The DNA polymerase will only incorporate acyclovir molecules.
c. The replication complex will no longer bind to origins of replication.
d. DNA polymerase will not be able to link a successive nucleotide.
e. Acyclovir will bind single-strand binding proteins.

Accepted Answer

The answer of The nucleoside analogue acyclovir, which is used...

Question 15

About how many rounds of PCR are required to produce a million DNA molecules from a single molecule, assuming that the PCR works perfectly?

Accepted Answer

A)  10 
B)  20 
C)  30 
D)  100 
E)  1,000 
A)  10 
B)  20 
C)  30 
D)  100 
E)  1,000

Question 16

What structural feature of DNA can disrupt the specificity of a protein-DNA interaction?

Accepted Answer

A)  DNA is a double-helix. 
B)  The genetic material is susceptible to mutations (permanent changes) in the information it encodes. 
C)  The genetic material (the coded information in DN
A)  is expressed as the phenotype. 
D)  The two DNA strands are antiparallel. 
E)  DNA's base pairing is complementary. 
A)  DNA is a double-helix. 
B)  The genetic material is susceptible to mutations (permanent changes) in the information it encodes. 
C)  The genetic material (the coded information in DN
A)  is expressed as the phenotype. 
D)  The two DNA strands are antiparallel. 
E)  DNA's base pairing is complementary.

Question 17

The proofreading DNA repair system differs from other types of DNA repair in that it

Accepted Answer

A)  does not actually decrease the mutation rate. 
B)  can only occur in prokaryotes. 
C)  can only occur in eukaryotes. 
D)  occurs as DNA is being replicated. 
E)  removes abnormal bases that have formed because of chemical damage. 
A)  does not actually decrease the mutation rate. 
B)  can only occur in prokaryotes. 
C)  can only occur in eukaryotes. 
D)  occurs as DNA is being replicated. 
E)  removes abnormal bases that have formed because of chemical damage.

Question 18

If a sequence of one strand of DNA is 5F1F1F1S1F1F1F10-TGACTATC-3F1F1F1S1F1F1F10, what is the complementary strand?
a. 5F1F1F1S1F1F1F10-ACTGATAG-3F1F1F1S1F1F1F10
b. 3F1F1F1S1F1F1F10-ACTGATAG-5F1F1F1S1F1F1F10
c. 3F1F1F1S1F1F1F10-ACTGATAG-3F1F1F1S1F1F1F10
d. 3F1F1F1S1F1F1F10-TGACTATC-5F1F1F1S1F1F1F10
e. 5F1F1F1S1F1F1F10-TGACTATC-3F1F1F1S1F1F1F10

Accepted Answer

The answer of If a sequence of one strand of...

Question 19

Prior to the Hershey and Chase blender experiment, many biologists were skeptical that DNA was the genetic material.These biologists thought that proteins might be the genetic material because proteins

Accepted Answer

A)  are twice as abundant in somatic cells as they are in the gametes. 
B)  can be labeled with isotopes. 
C)  are more structurally diverse than DNA is. 
D)  can transform bacteria. 
E)  contain sulfur. 
A)  are twice as abundant in somatic cells as they are in the gametes. 
B)  can be labeled with isotopes. 
C)  are more structurally diverse than DNA is. 
D)  can transform bacteria. 
E)  contain sulfur.

Question 20

Choose the correct order of the following four events in the excision repair of DNA:
(1) Base-paired DNA is made complementary to the template.
(2) Damaged bases are recognized.
(3) DNA ligase seals the new strand to existing DNA.
(4) Part of a single strand is excised.
a. 1, 2, 3, 4
b. 2, 1, 3, 4
c. 2, 4, 1, 3
d. 3, 4, 2, 1
e. 4, 2, 3, 1

Accepted Answer

The answer of Choose the correct order of the following...

Exam 13: Dna and Its Role in Heredity

Meselson and Stahl used heavy nitrogen (15N) in their experiments to

The molecules that function to replicate DNA in the cell are

Mutations are

If a G-T base pair is found in a newly replicated DNA molecule after proofreading, the _______ repair mechanism might replace the G with an A.

Before Watson and Crick built their DNA model, the American chemist and Nobel laureate Linus Pauling proposed a triple-helix model for DNA.What evidence convinced Watson and Crick to reject this model for the double-helix model?

If the proportion of C in a double-stranded DNA molecule is x, what is the proportion of T?

What structural aspect of the DNA facilitates dissociation of the two DNA strands for replication? a. Purine-pyrimidine pairing b. Hydrogen bonding between paired bases c. Covalent bonds between sugars and phosphate groups d. 3 end phosphorylation e. Antiparallel DNA strands

Which material serves as the template in DNA synthesis?

An automated process that makes multiple copies of short regions of DNA in a test tube is called _______.

Refer to the figure, which shows double-stranded DNA being prepared for DNA replication. What proteins (not shown) act on the DNA to unwind and dissociate the strands, and what proteins (not shown) keep the template strands separated?

Refer to the figure. Which letter refers to an Okazaki fragment?

If a sequence of one strand of DNA is 5ʹ-ATGATGT-3ʹ, the complementary strand must be _______.(Include correct orientation.)

About how many rounds of PCR are required to produce a million DNA molecules from a single molecule, assuming that the PCR works perfectly?

What structural feature of DNA can disrupt the specificity of a protein-DNA interaction?

The proofreading DNA repair system differs from other types of DNA repair in that it

If a sequence of one strand of DNA is 5-TGACTATC-3, what is the complementary strand? a. 5-ACTGATAG-3 b. 3-ACTGATAG-5 c. 3-ACTGATAG-3 d. 3-TGACTATC-5 e. 5-TGACTATC-3

Prior to the Hershey and Chase blender experiment, many biologists were skeptical that DNA was the genetic material.These biologists thought that proteins might be the genetic material because proteins

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Meselson and Stahl used heavy nitrogen (¹⁵N) in their experiments to