Question 1

What is the difference between the leading strand and the lagging strand in DNA replication?

Accepted Answer

A) The leading strand is synthesized in the 3' → 5' direction in a discontinuous fashion, while the lagging strand is synthesized in the 5'→ 3' direction in a continuous fashion. 
B) The leading strand is synthesized continuously in the 5'→ 3' direction, while the lagging strand is synthesized discontinuously in the 5'→ 3' direction. 
C) The leading strand requires an RNA primer, whereas the lagging strand does not. 
D) There are different DNA polymerases involved in elongation of the leading strand and the lagging strand. 
E) The leading strand is synthesized in the 3' → 5' direction in a continuous fashion, while the lagging strand is synthesized in the 5'→ 3' direction in a discontinuous fashion. 
A) The leading strand is synthesized in the 3' → 5' direction in a discontinuous fashion, while the lagging strand is synthesized in the 5'→ 3' direction in a continuous fashion. 
B) The leading strand is synthesized continuously in the 5'→ 3' direction, while the lagging strand is synthesized discontinuously in the 5'→ 3' direction. 
C) The leading strand requires an RNA primer, whereas the lagging strand does not. 
D) There are different DNA polymerases involved in elongation of the leading strand and the lagging strand. 
E) The leading strand is synthesized in the 3' → 5' direction in a continuous fashion, while the lagging strand is synthesized in the 5'→ 3' direction in a discontinuous fashion.

Question 2

Who performed classic experiments that supported the semiconservative model of DNA replication?

Accepted Answer

A) Watson and Crick 
B) Meselson and Stahl 
C) Hershey and Chase 
D) Franklin and Wilkins 
E) Avery 
A) Watson and Crick 
B) Meselson and Stahl 
C) Hershey and Chase 
D) Franklin and Wilkins 
E) Avery

Question 3

If a cell were unable to produce histone proteins,which of the following would be a likely effect?

Accepted Answer

A) There would be an increase in the amount of "satellite" DNA produced during centrifugation. 
B) The cell's DNA couldn't be packed into its nucleus. 
C) Spindle fibres would not form during prophase. 
D) Amplification of other genes would compensate for the lack of histones. 
E) Pseudogenes would be transcribed to compensate for the decreased protein in the cell. 
A) There would be an increase in the amount of "satellite" DNA produced during centrifugation. 
B) The cell's DNA couldn't be packed into its nucleus. 
C) Spindle fibres would not form during prophase. 
D) Amplification of other genes would compensate for the lack of histones. 
E) Pseudogenes would be transcribed to compensate for the decreased protein in the cell.

Question 4

What would the results have been if Hershey and Chase had used an RNA virus for their experiments?

Accepted Answer

A) With an RNA virus radioactive protein would have been in the final pellet. 
B) With an RNA virus radioactive RNA would have been in the final pellet. 
C) With an RNA virus the liquid portion would have been radioactive. 
D) With an RNA virus the protein shell would have been radioactive in both samples. 
E) It is not possible to predict the results. 
A) With an RNA virus radioactive protein would have been in the final pellet. 
B) With an RNA virus radioactive RNA would have been in the final pellet. 
C) With an RNA virus the liquid portion would have been radioactive. 
D) With an RNA virus the protein shell would have been radioactive in both samples. 
E) It is not possible to predict the results.

Question 5

In his transformation experiments,what did Griffith observe?

Accepted Answer

A) Mutant mice were resistant to bacterial infections. 
B) Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form. 
C) Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain makes the pathogenic strain nonpathogenic. 
D) Infecting mice with nonpathogenic strains of bacteria makes them resistant to pathogenic strains. 
E) Mice infected with a pathogenic strain of bacteria can spread the infection to other mice. 
A) Mutant mice were resistant to bacterial infections. 
B) Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form. 
C) Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain makes the pathogenic strain nonpathogenic. 
D) Infecting mice with nonpathogenic strains of bacteria makes them resistant to pathogenic strains. 
E) Mice infected with a pathogenic strain of bacteria can spread the infection to other mice.

Question 6

An Okazaki fragment has which of the following arrangements?

Accepted Answer

A) primase, polymerase, ligase 
B) 3' RNA nucleotides, DNA nucleotides 5' 
C) 5' RNA nucleotides, DNA nucleotides 3' 
D) DNA polymerase I, DNA polymerase III 
E) 5' DNA to 3' 
A) primase, polymerase, ligase 
B) 3' RNA nucleotides, DNA nucleotides 5' 
C) 5' RNA nucleotides, DNA nucleotides 3' 
D) DNA polymerase I, DNA polymerase III 
E) 5' DNA to 3'

Question 7

The experiments that led to the discovery of Okazaki fragments gave evidence for which of the following ideas?

Accepted Answer

A) DNA polymerase is a directional enzyme that synthesizes leading and lagging strands during replication. 
B) DNA is a polymer consisting of four monomers: adenine, thymine, guanine, and cytosine. 
C) DNA is the genetic material. 
D) Bacterial replication is fundamentally different from eukaryotic replication. 
E) Replication occurs in the 3' to 5' direction. 
A) DNA polymerase is a directional enzyme that synthesizes leading and lagging strands during replication. 
B) DNA is a polymer consisting of four monomers: adenine, thymine, guanine, and cytosine. 
C) DNA is the genetic material. 
D) Bacterial replication is fundamentally different from eukaryotic replication. 
E) Replication occurs in the 3' to 5' direction.

Question 8

Use the following figure to answer the questions below.
  
-Once the pattern found after one round of replication was observed,Meselson and Stahl could be confident of which of the following conclusions?

Accepted Answer

A) Replication is semi-conservative. 
B) Replication is not dispersive. 
C) Replication is not semi-conservative. 
D) Replication is not conservative. 
E) Replication is neither dispersive nor conservative. 
A) Replication is semi-conservative. 
B) Replication is not dispersive. 
C) Replication is not semi-conservative. 
D) Replication is not conservative. 
E) Replication is neither dispersive nor conservative.

Question 9

Which of the enzymes covalently connects segments of DNA?

Accepted Answer

A) helicase 
B) topoisomerase 
C) DNA ligase 
D) single-stranded binding protein 
E) primase 
A) helicase 
B) topoisomerase 
C) DNA ligase 
D) single-stranded binding protein 
E) primase

Question 10

Which of the following can be determined directly from X-ray diffraction photographs of crystallized DNA?

Accepted Answer

A) the diameter of the helix 
B) the rate of replication 
C) the sequence of nucleotides 
D) the bond angles of the subunits 
E) the frequency of A vs. T nucleotides 
A) the diameter of the helix 
B) the rate of replication 
C) the sequence of nucleotides 
D) the bond angles of the subunits 
E) the frequency of A vs. T nucleotides

Question 11

Individuals with the disorder xeroderma pigmentosum are hypersensitive to sunlight.This occurs because their cells are impaired in what way?

Accepted Answer

A) They cannot replicate DNA. 
B) They cannot undergo mitosis. 
C) They cannot exchange DNA with other cells. 
D) They cannot repair thymine dimers. 
E) They do not recombine homologous chromosomes during meiosis. 
A) They cannot replicate DNA. 
B) They cannot undergo mitosis. 
C) They cannot exchange DNA with other cells. 
D) They cannot repair thymine dimers. 
E) They do not recombine homologous chromosomes during meiosis.

Question 12

These calculations follow what rule?

Accepted Answer

A) the rule of diminishing returns 
B) Chargaff's rule 
C) Mendel's law 
D) the 5' - 3' rule 
E) the rule of linkage 
A) the rule of diminishing returns 
B) Chargaff's rule 
C) Mendel's law 
D) the 5' - 3' rule 
E) the rule of linkage

Question 13

What catalyzes the formation of phosphodiester bonds between adjacent nucleotides in the DNA polymer being formed?

Accepted Answer

A) ribozymes 
B) DNA polymerase 
C) ATP 
D) deoxyribonucleotide triphosphates 
E) helicase 
A) ribozymes 
B) DNA polymerase 
C) ATP 
D) deoxyribonucleotide triphosphates 
E) helicase

Question 14

At a specific area of a chromosome,the sequence of nucleotides below is present where the chain opens to form a replication fork:
3' C C T A G G C T G C A A T C C 5'
An RNA primer is formed starting at the underlined T (T)of the template.Which of the following represents the primer sequence?

Accepted Answer

A) 5' G C C T A G G 3' 
B) 3' G C C T A G G 5' 
C) 5' A C G T T A G G 3' 
D) 5' A C G U U A G G 3' 
E) 5' G C C U A G G 3' 
A) 5' G C C T A G G 3' 
B) 3' G C C T A G G 5' 
C) 5' A C G T T A G G 3' 
D) 5' A C G U U A G G 3' 
E) 5' G C C U A G G 3'

Question 15

Which of the following statements describes the eukaryotic chromosome?

Accepted Answer

A) It is composed of DNA alone. 
B) The nucleosome is its most basic functional subunit. 
C) The number of genes on each chromosome is different in different cell types of an organism. 
D) It consists of a single linear molecule of double-stranded DNA plus proteins. 
E) Active transcription occurs on heterochromatin but not euchromatin. 
A) It is composed of DNA alone. 
B) The nucleosome is its most basic functional subunit. 
C) The number of genes on each chromosome is different in different cell types of an organism. 
D) It consists of a single linear molecule of double-stranded DNA plus proteins. 
E) Active transcription occurs on heterochromatin but not euchromatin.

Question 16

Which of the enzymes synthesizes short segments of RNA?

Accepted Answer

A) helicase 
B) topoisomerase 
C) single-stranded binding protein 
D) DNA polymerase I 
E) primase 
A) helicase 
B) topoisomerase 
C) single-stranded binding protein 
D) DNA polymerase I 
E) primase

Question 17

The images above are of DNA at various levels of coiling and folding.Use this image to answer the questions below.
-Which image represents the 10 nm fibre,showing nucleosomes?

Accepted Answer

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

Question 18

To repair a thymine dimer by nucleotide excision repair,in which order do the necessary enzymes act?

Accepted Answer

A) exonuclease, DNA polymerase III, RNA primase 
B) helicase, DNA polymerase I, DNA ligase 
C) DNA ligase, nuclease, helicase 
D) DNA polymerase I, DNA polymerase III, DNA ligase 
E) endonuclease, DNA polymerase I, DNA ligase 
A) exonuclease, DNA polymerase III, RNA primase 
B) helicase, DNA polymerase I, DNA ligase 
C) DNA ligase, nuclease, helicase 
D) DNA polymerase I, DNA polymerase III, DNA ligase 
E) endonuclease, DNA polymerase I, DNA ligase

Question 19

The images above are of DNA at various levels of coiling and folding.Use this image to answer the questions below.
-Which image represents the chromatid?

Accepted Answer

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

Question 20

Cytosine makes up 42% of the nucleotides in a sample of DNA from an organism.Approximately what percentage of the nucleotides in this sample will be thymine?

Accepted Answer

A) 8% 
B) 16% 
C) 31% 
D) 42% 
E) It cannot be determined from the information provided. 
A) 8% 
B) 16% 
C) 31% 
D) 42% 
E) It cannot be determined from the information provided.

Exam 16: The Molecular Basis of Inheritance

What is the difference between the leading strand and the lagging strand in DNA replication?

Who performed classic experiments that supported the semiconservative model of DNA replication?

If a cell were unable to produce histone proteins,which of the following would be a likely effect?

What would the results have been if Hershey and Chase had used an RNA virus for their experiments?

In his transformation experiments,what did Griffith observe?

An Okazaki fragment has which of the following arrangements?

The experiments that led to the discovery of Okazaki fragments gave evidence for which of the following ideas?

Use the following figure to answer the questions below. -Once the pattern found after one round of replication was observed,Meselson and Stahl could be confident of which of the following conclusions?

Which of the enzymes covalently connects segments of DNA?

Which of the following can be determined directly from X-ray diffraction photographs of crystallized DNA?

Individuals with the disorder xeroderma pigmentosum are hypersensitive to sunlight.This occurs because their cells are impaired in what way?

These calculations follow what rule?

What catalyzes the formation of phosphodiester bonds between adjacent nucleotides in the DNA polymer being formed?

At a specific area of a chromosome,the sequence of nucleotides below is present where the chain opens to form a replication fork: 3' C C T A G G C T G C A A T C C 5' An RNA primer is formed starting at the underlined T (T)of the template.Which of the following represents the primer sequence?

Which of the following statements describes the eukaryotic chromosome?

Which of the enzymes synthesizes short segments of RNA?

The images above are of DNA at various levels of coiling and folding.Use this image to answer the questions below. -Which image represents the 10 nm fibre,showing nucleosomes?

To repair a thymine dimer by nucleotide excision repair,in which order do the necessary enzymes act?

The images above are of DNA at various levels of coiling and folding.Use this image to answer the questions below. -Which image represents the chromatid?

Cytosine makes up 42% of the nucleotides in a sample of DNA from an organism.Approximately what percentage of the nucleotides in this sample will be thymine?

Introduction: Evolution and Themes of Biology

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure,Growth,and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons,Synapses,and Signalling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behaviour

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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