Question 1

In DNA replication,each newly made strand is

Accepted Answer

A)  identical in DNA sequence to the strand from which it was copied. 
B)  an incomplete copy of one of the parental strands. 
C)  oriented in the same 3'-to-5'direction as the strand from which it was copied. 
D)  complementary in sequence to the strand from which it was copied. 
E)  a hybrid molecule consisting of both ribo- and deoxyribonucleotides. 
A)  identical in DNA sequence to the strand from which it was copied. 
B)  an incomplete copy of one of the parental strands. 
C)  oriented in the same 3'-to-5'direction as the strand from which it was copied. 
D)  complementary in sequence to the strand from which it was copied. 
E)  a hybrid molecule consisting of both ribo- and deoxyribonucleotides. D

Question 2

The first repair of mistakes during DNA replication is made by

Accepted Answer

A)  the mismatch repair system. 
B)  DNA polymerase. 
C)  excision repair. 
D)  SOS repair. 
E)  post-replication repair. 
A)  the mismatch repair system. 
B)  DNA polymerase. 
C)  excision repair. 
D)  SOS repair. 
E)  post-replication repair. B

Question 3

Double-stranded DNA looks like a ladder that has been twisted into a helix,or spiral.The rungs of the ladder are

Accepted Answer

A)  individual nitrogenous bases. 
B)  pairs of bases. 
C)  alternating bases and phosphate groups. 
D)  alternating sugars and bases. 
E)  alternating bases,sugars,and phosphates. 
A)  individual nitrogenous bases. 
B)  pairs of bases. 
C)  alternating bases and phosphate groups. 
D)  alternating sugars and bases. 
E)  alternating bases,sugars,and phosphates. B

Question 4

Starting with a single double-stranded DNA molecule,_______ double-stranded DNA molecules will exist after five rounds of PCR (assuming that the PCR works perfectly).

Accepted Answer

A)  5 
B)  10 
C)  16 
D)  32 
E)  1,024 
A)  5 
B)  10 
C)  16 
D)  32 
E)  1,024

Question 5

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.

Question 6

A research laboratory uses a cancer cell line that has undergone thousands of cell cycle divisions in the laboratory without any change in the length of its chromosomes.The cancer cell line is therefore likely to express

Accepted Answer

A)  high levels of RNA polymerase. 
B)  very low levels of telomerase. 
C)  high levels of telomerase. 
D)  DNA polymerases with high fidelity. 
E)  high levels of ligase activity. 
A)  high levels of RNA polymerase. 
B)  very low levels of telomerase. 
C)  high levels of telomerase. 
D)  DNA polymerases with high fidelity. 
E)  high levels of ligase activity.

Question 7

If a double-stranded DNA molecule contains 30 percent T,it must contain _______ percent G.

Accepted Answer

A)  20 
B)  30 
C)  40 
D)  50 
E)  60 
A)  20 
B)  30 
C)  40 
D)  50 
E)  60

Question 8

The DNA isolated from a newly discovered virus is found to be 32 percent A,18 percent C,18 percent G,and 32 percent T.The base composition of the complementary DNA would be _______ percent A,_______ percent C,_______ percent G,and _______ percent T.

Accepted Answer

A)  32;17;32;19 
B)  19;32;17;32 
C)  17;32;32;19 
D)  25;25;25;25 
E)  32;18;18;32 
A)  32;17;32;19 
B)  19;32;17;32 
C)  17;32;32;19 
D)  25;25;25;25 
E)  32;18;18;32

Question 9

The role of DNA ligase in DNA replication is to

Accepted Answer

A)  add more nucleotides to the growing strand,one at a time. 
B)  open up the two DNA strands to expose template strands. 
C)  ligate base to sugar to phosphate in a nucleotide. 
D)  bond Okazaki fragments to one another. 
E)  remove incorrectly paired bases. 
A)  add more nucleotides to the growing strand,one at a time. 
B)  open up the two DNA strands to expose template strands. 
C)  ligate base to sugar to phosphate in a nucleotide. 
D)  bond Okazaki fragments to one another. 
E)  remove incorrectly paired bases.

Question 10

Mutational "hot spots" often occur when a methyl group has been added to

Accepted Answer

A)  adenine. 
B)  cytosine. 
C)  guanine. 
D)  thymine. 
E)  uracil. 
A)  adenine. 
B)  cytosine. 
C)  guanine. 
D)  thymine. 
E)  uracil.

Question 11

Pyrophosphate is a

Accepted Answer

A)  building block for DNA synthesis. 
B)  by-product of DNA synthesis. 
C)  precursor to DNA synthesis. 
D)  radioactive phosphate used in nucleic acid metabolism. 
E)  link between sugar molecules. 
A)  building block for DNA synthesis. 
B)  by-product of DNA synthesis. 
C)  precursor to DNA synthesis. 
D)  radioactive phosphate used in nucleic acid metabolism. 
E)  link between sugar molecules.

Question 12

The characteristic of DNA that allows it to make an exact copy of itself is

Accepted Answer

A)  its sugar-phosphate backbone. 
B)  its complementary base pairing. 
C)  the phosphodiester bonding of the helices. 
D)  the twisting of the molecule to form an $\alpha$helix. 
E)  its antiparallel strands. 
A)  its sugar-phosphate backbone. 
B)  its complementary base pairing. 
C)  the phosphodiester bonding of the helices. 
D)  the twisting of the molecule to form an $\alpha$helix. 
E)  its antiparallel strands.

Question 13

Which statement about infection of E.coli cells by bacteriophage T2 is true?

Accepted Answer

A)  Proteins are the only phage components that enter the infected cell. 
B)  Both proteins and nucleic acids enter the cell. 
C)  Only protein from the infecting phage can be detected in progeny phage. 
D)  Nucleic acids,but not protein,enter the cell. 
E)  More than one phage particle is required to produce infection. 
A)  Proteins are the only phage components that enter the infected cell. 
B)  Both proteins and nucleic acids enter the cell. 
C)  Only protein from the infecting phage can be detected in progeny phage. 
D)  Nucleic acids,but not protein,enter the cell. 
E)  More than one phage particle is required to produce infection.

Question 14

The primary information source used by Watson and Crick to determine the structure of DNA was

Accepted Answer

A)  electron micrographs of individual DNA molecules. 
B)  light micrographs of bacteriophage particles. 
C)  light micrographs of individual bacterial chromosomes. 
D)  nuclear magnetic resonance analysis of DNA. 
E)  X-ray crystallography of double-stranded DNA. 
A)  electron micrographs of individual DNA molecules. 
B)  light micrographs of bacteriophage particles. 
C)  light micrographs of individual bacterial chromosomes. 
D)  nuclear magnetic resonance analysis of DNA. 
E)  X-ray crystallography of double-stranded DNA.

Question 15

Which statement about base pairing is false?

Accepted Answer

A)  Purines pair with purines,and pyrimidines pair with pyrimidines. 
B)  In DNA,T pairs with A. 
C)  Complementary base pairing plays a role in DNA replication. 
D)  In DNA,C pairs with G. 
E)  The base pairs are of equal length. 
A)  Purines pair with purines,and pyrimidines pair with pyrimidines. 
B)  In DNA,T pairs with A. 
C)  Complementary base pairing plays a role in DNA replication. 
D)  In DNA,C pairs with G. 
E)  The base pairs are of equal length.

Question 16

Benzopyrene,a component of cigarette smoke,can induce DNA mutations by

Accepted Answer

A)  converting cytosine to uracil by deamination. 
B)  converting an amino group on cytosine into a keto group. 
C)  adding a chemical to guanine,making it unavailable for base pairing. 
D)  changing bases to forms that are unrecognizable by DNA polymerase. 
E)  breaking the sugar-phosphate backbone of DNA. 
A)  converting cytosine to uracil by deamination. 
B)  converting an amino group on cytosine into a keto group. 
C)  adding a chemical to guanine,making it unavailable for base pairing. 
D)  changing bases to forms that are unrecognizable by DNA polymerase. 
E)  breaking the sugar-phosphate backbone of DNA.

Question 17

A virus that infects bacteria is called a _______.

Accepted Answer

The answer of A virus that infects bacteria is called...

Question 18

In eukaryotes,Okazaki fragments are about _______ base pairs long.

Accepted Answer

A)  5-10 
B)  100-200 
C)  500-1,000 
D)  1,000-2,000 
E)  10,000-20,000 
A)  5-10 
B)  100-200 
C)  500-1,000 
D)  1,000-2,000 
E)  10,000-20,000

Question 19

In the 1920s,a dye was developed that binds to DNA and stains nuclei in direct proportion to the amount of DNA present in the cells.The resulting experiments

Accepted Answer

A)  provided circumstantial evidence that DNA is the genetic material. 
B)  demonstrated that DNA is the genetic material. 
C)  demonstrated that all species have the same amount of nuclear DNA. 
D)  demonstrated that diploid and haploid cells cannot have differing amounts of DNA. 
E)  confirmed that DNA is an important component of mitochondria and chloroplasts. 
A)  provided circumstantial evidence that DNA is the genetic material. 
B)  demonstrated that DNA is the genetic material. 
C)  demonstrated that all species have the same amount of nuclear DNA. 
D)  demonstrated that diploid and haploid cells cannot have differing amounts of DNA. 
E)  confirmed that DNA is an important component of mitochondria and chloroplasts.

Question 20

People with sickle-cell disease have

Accepted Answer

A)  defective phenylalanine hydrolyase. 
B)  a defective oncogene. 
C)  abnormal cholesterol transport. 
D)  defective hemoglobin. 
E)  an abnormality in their DNA replication. 
A)  defective phenylalanine hydrolyase. 
B)  a defective oncogene. 
C)  abnormal cholesterol transport. 
D)  defective hemoglobin. 
E)  an abnormality in their DNA replication.

Exam 9: DNA and Its Role in Heredity

In DNA replication,each newly made strand is

The first repair of mistakes during DNA replication is made by

Double-stranded DNA looks like a ladder that has been twisted into a helix,or spiral.The rungs of the ladder are

Starting with a single double-stranded DNA molecule,_______ double-stranded DNA molecules will exist after five rounds of PCR (assuming that the PCR works perfectly).

The molecules that function to replicate DNA in the cell are

A research laboratory uses a cancer cell line that has undergone thousands of cell cycle divisions in the laboratory without any change in the length of its chromosomes.The cancer cell line is therefore likely to express

If a double-stranded DNA molecule contains 30 percent T,it must contain _______ percent G.

The DNA isolated from a newly discovered virus is found to be 32 percent A,18 percent C,18 percent G,and 32 percent T.The base composition of the complementary DNA would be _______ percent A,_______ percent C,_______ percent G,and _______ percent T.

The role of DNA ligase in DNA replication is to

Mutational "hot spots" often occur when a methyl group has been added to

Pyrophosphate is a

The characteristic of DNA that allows it to make an exact copy of itself is

Which statement about infection of E.coli cells by bacteriophage T2 is true?

The primary information source used by Watson and Crick to determine the structure of DNA was

Which statement about base pairing is false?

Benzopyrene,a component of cigarette smoke,can induce DNA mutations by

A virus that infects bacteria is called a _______.

In eukaryotes,Okazaki fragments are about _______ base pairs long.

In the 1920s,a dye was developed that binds to DNA and stains nuclei in direct proportion to the amount of DNA present in the cells.The resulting experiments

People with sickle-cell disease have

Introduction

The Chemistry and Energy of Life

Nucleic Acids, Proteins, and Enzymes

Cells: the Working Units of Life

Cell Membranes and Signaling

Pathways That Harvest and Store Chemical Energy

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

From Dna to Protein: Gene Expression

Regulation of Gene Expression

Genomes

Biotechnology

Genes, Development, and Evolution

Processes of Evolution

Reconstructing and Using Phylogenies

Speciation

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

The Evolution of Plants

The Evolution and Diversity of Fungi

Animal Origins and Diversity

The Plant Body

Plant Nutrition and Transport

Plant Growth and Development

Reproduction of Flowering Plants

Plants in the Environment

Fundamentals of Animal Function

Nutrition and Digestion

Breathing

Circulation

Muscle and Movement

Neurons, Sense Organs, and Nervous Systems

Nervous and Endocrine Control

Water and Salts: Excretion

Animal Reproduction

Animal Development

Immunology: Animal Defense Systems

Animal Behavior

The Distribution of Earths Ecological Systems

Populations

Ecological and Evolutionary Consequences of Interactions Within and Among Species

Ecological Communities

The Global Ecosystem

Filters

The DNA isolated from a newly discovered virus is found to be 32 percent A,18 percent C,18 percent G,and 32 percent T.The base composition of the complementary DNA would be ___ percent A,_ percent C,_ percent G,and ___ percent T.