Question 1

In DNA replication,the processive nature of DNA polymerase

Accepted Answer

A)  increases the number of nucleotides that can be polymerized per enzymatic cycle. 
B)  holds open the two strands of the DNA molecule for access to the bonds. 
C)  allows it to jump from one DNA strand to another. 
D)  temporarily holds the nucleotides together until phosphodiester bonds can form. 
E)  unwinds the double helix to allow the DNA polymerase to bind. 
A)  increases the number of nucleotides that can be polymerized per enzymatic cycle. 
B)  holds open the two strands of the DNA molecule for access to the bonds. 
C)  allows it to jump from one DNA strand to another. 
D)  temporarily holds the nucleotides together until phosphodiester bonds can form. 
E)  unwinds the double helix to allow the DNA polymerase to bind.

Question 2

If a mutation changes a G to an A on one strand of a DNA molecule,with a corresponding change in its complement,which property will most likely be affected?

Accepted Answer

A)  The width of the DNA molecule 
B)  The length of the DNA molecule 
C)  The nature of protein-DNA interactions 
D)  The number of purines in the double-stranded molecule 
E)  All of the above are equally likely. 
A)  The width of the DNA molecule 
B)  The length of the DNA molecule 
C)  The nature of protein-DNA interactions 
D)  The number of purines in the double-stranded molecule 
E)  All of the above are equally likely.

Question 3

The fidelity of eukaryotic DNA replication is astounding.During DNA synthesis,the frequency of errors is about 1 incorrect base in _______ nucleotides inserted.

Accepted Answer

A)  1,000 
B)  5,000 
C)  10,000 
D)  50,000 
E)  100,000 
A)  1,000 
B)  5,000 
C)  10,000 
D)  50,000 
E)  100,000

Question 4

Mutations are

Accepted Answer

A)  heritable changes in the sequence of DNA bases that always produce an observable phenotype. 
B)  changes in the nucleotide sequence of DNA that is passed on from one organism to another. 
C)  mistakes in the incorporation of amino acids into proteins. 
D)  heritable changes in the mRNA of an organism. 
E)  nucleotide changes that occur only in gametes. 
A)  heritable changes in the sequence of DNA bases that always produce an observable phenotype. 
B)  changes in the nucleotide sequence of DNA that is passed on from one organism to another. 
C)  mistakes in the incorporation of amino acids into proteins. 
D)  heritable changes in the mRNA of an organism. 
E)  nucleotide changes that occur only in gametes.

Question 5

Without DNA repair,the error rate of DNA polymerase is about one for every hundred thousand bases replicated.If an organism has a haploid genome of 2 billion base pairs,how many mutations are likely to occur each time a diploid cell replicates its DNA?

Accepted Answer

A)  20 
B)  40 
C)  80 
D)  20,000 
E)  40,000 
A)  20 
B)  40 
C)  80 
D)  20,000 
E)  40,000

Question 6

DNA is held together in a double helix by the force of

Accepted Answer

A)  the twist. 
B)  covalent bonds. 
C)  ionic bonds. 
D)  ionic interactions. 
E)  hydrogen bonds. 
A)  the twist. 
B)  covalent bonds. 
C)  ionic bonds. 
D)  ionic interactions. 
E)  hydrogen bonds.

Question 7

Which statement about the molecular architecture of the standard configuration of DNA is false?

Accepted Answer

A)  The two strands run in opposite directions. 
B)  The molecule's twist is left-handed. 
C)  The molecule is a double-stranded helix. 
D)  It has a uniform diameter. 
E)  The helix has major and minor grooves. 
A)  The two strands run in opposite directions. 
B)  The molecule's twist is left-handed. 
C)  The molecule is a double-stranded helix. 
D)  It has a uniform diameter. 
E)  The helix has major and minor grooves.

Question 8

The polymerase chain reaction

Accepted Answer

A)  is a method for sequencing DNA. 
B)  is used to transcribe specific genes. 
C)  amplifies specific DNA sequences. 
D)  does not require DNA replication primers. 
E)  uses a DNA polymerase that denatures at 55°C and above. 
A)  is a method for sequencing DNA. 
B)  is used to transcribe specific genes. 
C)  amplifies specific DNA sequences. 
D)  does not require DNA replication primers. 
E)  uses a DNA polymerase that denatures at 55°C and above.

Question 9

Which feature of the Watson and Crick model of DNA structure explains its ability to function in replication and gene expression?

Accepted Answer

A)  Each strand contains all the information present in the double helix. 
B)  There are structural and functional similarities between DNA and RNA. 
C)  The double helix is right-handed,not left-handed. 
D)  DNA replication does not require enzyme catalysts. 
E)  Bases are exposed in the major groove of the double helix. 
A)  Each strand contains all the information present in the double helix. 
B)  There are structural and functional similarities between DNA and RNA. 
C)  The double helix is right-handed,not left-handed. 
D)  DNA replication does not require enzyme catalysts. 
E)  Bases are exposed in the major groove of the double helix.

Question 10

Who first suggested a mode of replication for DNA?

Accepted Answer

A)  Erwin Chargaff 
B)  Hershey and Chase 
C)  Rosalind Franklin 
D)  Watson and Crick 
E)  Gregor Mendel 
A)  Erwin Chargaff 
B)  Hershey and Chase 
C)  Rosalind Franklin 
D)  Watson and Crick 
E)  Gregor Mendel

Question 11

An alien DNA-like molecule is isolated from the frozen remains of a life form found beneath the Martian polar ice caps.In this sample,for every base designated Q,there is twice that amount of base R;for every base Z,there is twice that amount of base S.If the molecule contains 33.33 percent R,what percentage of Z would you expect to find?

Accepted Answer

A)  6 percent 
B)  12 percent 
C)  24 percent 
D)  16.67 percent 
E)  54.66 percent 
A)  6 percent 
B)  12 percent 
C)  24 percent 
D)  16.67 percent 
E)  54.66 percent

Question 12

Which molecule(s)function(s)to transfer information from one generation to the next in eukaryotes?

Accepted Answer

A)  DNA 
B)  mRNA 
C)  tRNA 
D)  Proteins 
E)  Lipids 
A)  DNA 
B)  mRNA 
C)  tRNA 
D)  Proteins 
E)  Lipids

Question 13

In a growing DNA strand,each monomer is added to which carbon of the deoxyribose?

Accepted Answer

A)  1' 
B)  2' 
C)  3' 
D)  4' 
E)  5' 
A)  1' 
B)  2' 
C)  3' 
D)  4' 
E)  5'

Question 14

What prevents the DNA repair system from "repairing" telomeres?

Accepted Answer

A)  Telomerase is bound to telomeres,and thus blocks the repair system from binding to telomeres. 
B)  Telomerase catalyzes reactions that interfere with the repair system. 
C)  DNA polymerase blocks the repair system from accessing the telomere DNA. 
D)  Telomeres are at the end of the chromosome,and DNA is replicated in only one direction. 
E)  Protective proteins bind to telomeres,and therefore the repair system does not recognize telomeres as breaks. 
A)  Telomerase is bound to telomeres,and thus blocks the repair system from binding to telomeres. 
B)  Telomerase catalyzes reactions that interfere with the repair system. 
C)  DNA polymerase blocks the repair system from accessing the telomere DNA. 
D)  Telomeres are at the end of the chromosome,and DNA is replicated in only one direction. 
E)  Protective proteins bind to telomeres,and therefore the repair system does not recognize telomeres as breaks.

Question 15

The primer used for DNA replication

Accepted Answer

A)  is a short strand of RNA added to the 5'end of the template strand. 
B)  is needed only once on a leading strand. 
C)  remains on the DNA after replication. 
D)  ensures that there will be a free 5' end to which nucleotides can be added. 
E)  is added to only one of the two template strands. 
A)  is a short strand of RNA added to the 5'end of the template strand. 
B)  is needed only once on a leading strand. 
C)  remains on the DNA after replication. 
D)  ensures that there will be a free 5' end to which nucleotides can be added. 
E)  is added to only one of the two template strands.

Question 16

A deoxyribonucleotide is a

Accepted Answer

A)  deoxyribose plus a nitrogenous base. 
B)  sugar and a phosphate. 
C)  nitrogenous base bonded at the 5' end to a sugar-phosphate backbone. 
D)  ribose plus a nitrogenous base. 
E)  deoxyribose plus a nitrogenous base and a phosphate group. 
A)  deoxyribose plus a nitrogenous base. 
B)  sugar and a phosphate. 
C)  nitrogenous base bonded at the 5' end to a sugar-phosphate backbone. 
D)  ribose plus a nitrogenous base. 
E)  deoxyribose plus a nitrogenous base and a phosphate group.

Question 17

Fragments like those now called Okazaki fragments might have been hypothesized even before they were discovered by Reiji Okazaki because

Accepted Answer

A)  DNA replicates in the 3'-to-5' direction. 
B)  single-stranded 5'-to-3' DNA appears behind DNA polymerase. 
C)  DNA nucleotides are added to the 5' end of the primer on the lagging strand. 
D)  RNA primase places short RNA primer sequences along the DNA molecule. 
E)  DNA polymerase I can connect short segments. 
A)  DNA replicates in the 3'-to-5' direction. 
B)  single-stranded 5'-to-3' DNA appears behind DNA polymerase. 
C)  DNA nucleotides are added to the 5' end of the primer on the lagging strand. 
D)  RNA primase places short RNA primer sequences along the DNA molecule. 
E)  DNA polymerase I can connect short segments.

Question 18

Individual cells do not survive for the entire lifetime of an organism because

Accepted Answer

A)  the enzyme telomerase is readily destroyed by the environment,resulting in cell death. 
B)  DNA replication is subject to errors that cause cell death. 
C)  Okazaki fragments disrupt protein synthesis,resulting in cell death. 
D)  the repeating telomeric sequence of TTAGGG interferes with normal DNA replication and leads to cell death. 
E)  the removal of the RNA primer following DNA replication leads to a shortening of the chromosome and eventual cell death. 
A)  the enzyme telomerase is readily destroyed by the environment,resulting in cell death. 
B)  DNA replication is subject to errors that cause cell death. 
C)  Okazaki fragments disrupt protein synthesis,resulting in cell death. 
D)  the repeating telomeric sequence of TTAGGG interferes with normal DNA replication and leads to cell death. 
E)  the removal of the RNA primer following DNA replication leads to a shortening of the chromosome and eventual cell death.

Question 19

Which statement about duplications and translocations is true?

Accepted Answer

A)  Translocations involve the loss of a chromosomal segment,whereas duplications involve the addition of an entire chromosome. 
B)  Duplications involve the breaking and swapping of DNA segments on homologous chromosomes,whereas translocations are reciprocal exchanges on nonhomologous chromosomes. 
C)  Translocations involve the breaking and insertion of DNA segments in reverse order,whereas duplications are the breaking of DNA at different points on the chromosome. 
D)  Duplications lead to duplications of the chromosome,whereas translocations involve the swapping of chromosome segments. 
E)  Translocations result in loss of chromosomal segments,whereas duplications result in significant additions to nonhomologous chromosomes. 
A)  Translocations involve the loss of a chromosomal segment,whereas duplications involve the addition of an entire chromosome. 
B)  Duplications involve the breaking and swapping of DNA segments on homologous chromosomes,whereas translocations are reciprocal exchanges on nonhomologous chromosomes. 
C)  Translocations involve the breaking and insertion of DNA segments in reverse order,whereas duplications are the breaking of DNA at different points on the chromosome. 
D)  Duplications lead to duplications of the chromosome,whereas translocations involve the swapping of chromosome segments. 
E)  Translocations result in loss of chromosomal segments,whereas duplications result in significant additions to nonhomologous chromosomes.

Question 20

A deoxyribonucleoside is a

Accepted Answer

A)  deoxyribose plus a nitrogenous base. 
B)  sugar and a phosphate. 
C)  deoxyribose plus a nitrogenous base and a phosphate. 
D)  ribose plus a nitrogenous base. 
E)  nitrogenous base bonded at the 5' end to a sugar-phosphate backbone. 
A)  deoxyribose plus a nitrogenous base. 
B)  sugar and a phosphate. 
C)  deoxyribose plus a nitrogenous base and a phosphate. 
D)  ribose plus a nitrogenous base. 
E)  nitrogenous base bonded at the 5' end to a sugar-phosphate backbone.

Exam 9: DNA and Its Role in Heredity

In DNA replication,the processive nature of DNA polymerase

If a mutation changes a G to an A on one strand of a DNA molecule,with a corresponding change in its complement,which property will most likely be affected?

The fidelity of eukaryotic DNA replication is astounding.During DNA synthesis,the frequency of errors is about 1 incorrect base in _______ nucleotides inserted.

Mutations are

Without DNA repair,the error rate of DNA polymerase is about one for every hundred thousand bases replicated.If an organism has a haploid genome of 2 billion base pairs,how many mutations are likely to occur each time a diploid cell replicates its DNA?

DNA is held together in a double helix by the force of

Which statement about the molecular architecture of the standard configuration of DNA is false?

The polymerase chain reaction

Which feature of the Watson and Crick model of DNA structure explains its ability to function in replication and gene expression?

Who first suggested a mode of replication for DNA?

Which molecule(s)function(s)to transfer information from one generation to the next in eukaryotes?

In a growing DNA strand,each monomer is added to which carbon of the deoxyribose?

What prevents the DNA repair system from "repairing" telomeres?

The primer used for DNA replication

A deoxyribonucleotide is a

Fragments like those now called Okazaki fragments might have been hypothesized even before they were discovered by Reiji Okazaki because

Individual cells do not survive for the entire lifetime of an organism because

Which statement about duplications and translocations is true?

A deoxyribonucleoside is a

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

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