Question 1

Early genes of a lytic bacteriophage are transcribed by

Accepted Answer

A)  late genes. 
B)  viral RNA polymerase from earlier lytic cycles. 
C)  host DNA polymerase. 
D)  reverse transcriptase. 
E)  host RNA polymerase. 
A)  late genes. 
B)  viral RNA polymerase from earlier lytic cycles. 
C)  host DNA polymerase. 
D)  reverse transcriptase. 
E)  host RNA polymerase.

Question 2

The HIV virus that causes AIDS is a(n)

Accepted Answer

A)  arbovirus. 
B)  double-stranded DNA virus. 
C)  single-stranded DNA virus. 
D)  porcine virus. 
E)  retrovirus. 
A)  arbovirus. 
B)  double-stranded DNA virus. 
C)  single-stranded DNA virus. 
D)  porcine virus. 
E)  retrovirus.

Question 3

In which of these pairs do the two entities act in opposite ways?

Accepted Answer

A)  A constitutive gene and an activator 
B)  A transcription factor and a constitutive gene 
C)  A repressor and an activator 
D)  A promoter and a repressor 
E)  A promoter and an activator 
A)  A constitutive gene and an activator 
B)  A transcription factor and a constitutive gene 
C)  A repressor and an activator 
D)  A promoter and a repressor 
E)  A promoter and an activator

Question 4

In comparison with genes in bacterial operons,genes that encode for stress responses in plants

Accepted Answer

A)  are located closer together on the chromosome. 
B)  do not alter their expression levels due to transcription factor binding. 
C)  are not coordinately regulated. 
D)  are located farther apart on the chromosome. 
E)  do not respond to changes in environmental conditions. 
A)  are located closer together on the chromosome. 
B)  do not alter their expression levels due to transcription factor binding. 
C)  are not coordinately regulated. 
D)  are located farther apart on the chromosome. 
E)  do not respond to changes in environmental conditions.

Question 5

What is a likely advantage of transcriptional regulation over allosteric regulation?

Accepted Answer

A)  In transcriptional regulation,only the final product is regulated;thus,it is more efficient. 
B)  In allosteric regulation,the continued production of enzymes is energetically costly.In transcriptional regulation,it is possible to shut down the production of the enzymes. 
C)  Allosteric regulation is necessarily slower than transcriptional regulation. 
D)  Allosteric regulation requires cofactors that are not required by transcriptional regulation. 
E)  Transcriptional regulation can be inducible or repressible. 
A)  In transcriptional regulation,only the final product is regulated;thus,it is more efficient. 
B)  In allosteric regulation,the continued production of enzymes is energetically costly.In transcriptional regulation,it is possible to shut down the production of the enzymes. 
C)  Allosteric regulation is necessarily slower than transcriptional regulation. 
D)  Allosteric regulation requires cofactors that are not required by transcriptional regulation. 
E)  Transcriptional regulation can be inducible or repressible.

Question 6

Genomic imprinting

Accepted Answer

A)  marks the parental origin of alleles. 
B)  explains why euchromatin and heterochromatin are different. 
C)  explains differences in the epigenomes of adult monozgotic twins. 
D)  alters the DNA sequence. 
E)  is not found in mammals. 
A)  marks the parental origin of alleles. 
B)  explains why euchromatin and heterochromatin are different. 
C)  explains differences in the epigenomes of adult monozgotic twins. 
D)  alters the DNA sequence. 
E)  is not found in mammals.

Question 7

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n)_______ operon and M acts as a(n)_______.

Accepted Answer

A)  repressible;inducer 
B)  repressible;transcription factor 
C)  inducible;inducer 
D)  inducible;corepressor 
E)  inducible;transcription factor 
A)  repressible;inducer 
B)  repressible;transcription factor 
C)  inducible;inducer 
D)  inducible;corepressor 
E)  inducible;transcription factor

Question 8

In eukaryotic cells,promoters are

Accepted Answer

A)  transcribed. 
B)  transcribed and translated. 
C)  sequences of RNA that are spliced out. 
D)  transcribed and then removed. 
E)  neither transcribed nor translated. 
A)  transcribed. 
B)  transcribed and translated. 
C)  sequences of RNA that are spliced out. 
D)  transcribed and then removed. 
E)  neither transcribed nor translated.

Question 9

Which statement about viruses is true?

Accepted Answer

A)  They are not cells. 
B)  They can regulate the movements of substances into and out of the cell. 
C)  They can reproduce outside living cells. 
D)  They are large and therefore easy to study. 
E)  They are the smallest life form. 
A)  They are not cells. 
B)  They can regulate the movements of substances into and out of the cell. 
C)  They can reproduce outside living cells. 
D)  They are large and therefore easy to study. 
E)  They are the smallest life form.

Question 10

Which statement about operons is false?

Accepted Answer

A)  The structural genes in the operon are either all on or all off at a given time. 
B)  They consist of a cluster of genes with a single promoter. 
C)  Their DNA is transcribed into a single molecule of mRNA. 
D)  They are the units of transcriptional regulation in prokaryotes. 
E)  A repressible operon is turned off unless needed. 
A)  The structural genes in the operon are either all on or all off at a given time. 
B)  They consist of a cluster of genes with a single promoter. 
C)  Their DNA is transcribed into a single molecule of mRNA. 
D)  They are the units of transcriptional regulation in prokaryotes. 
E)  A repressible operon is turned off unless needed.

Question 11

A normal E.coli cell that is grown for several hours in the presence of glucose alone will show _______ levels of the protein $\beta$-galactoside permease.A normal E.coli cell grown for several hours in the presence of lactase alone will show _______ levels of the protein $\beta$-galactoside permease.

Accepted Answer

A)  extremely low;high 
B)  extremely low;extremely low 
C)  high;extremely low 
D)  high;high 
E)  high;variable 
A)  extremely low;high 
B)  extremely low;extremely low 
C)  high;extremely low 
D)  high;high 
E)  high;variable

Question 12

What kind of mutation would lead to an increase in the expression (or inappropriate expression)of a gene?

Accepted Answer

A)  A mutation that lowers the efficiency of a repressor of the gene 
B)  A mutation that lowers the efficiency of an activator of the gene 
C)  A mutation that increases the efficiency of a repressor of the gene 
D)  A mutation that mutates an activator for the gene such that promoter recognition decreases 
E)  A mutation that mutates a repressor for the gene such that promoter recognition increases 
A)  A mutation that lowers the efficiency of a repressor of the gene 
B)  A mutation that lowers the efficiency of an activator of the gene 
C)  A mutation that increases the efficiency of a repressor of the gene 
D)  A mutation that mutates an activator for the gene such that promoter recognition decreases 
E)  A mutation that mutates a repressor for the gene such that promoter recognition increases

Question 13

The binding of TFIID to the promoter _______,thereby enabling the binding of other transcription factors.

Accepted Answer

A)  methylates the DNA 
B)  demethylates the DNA 
C)  changes the shape of the DNA 
D)  produces signals that attract other transcription factors 
E)  blocks the RNA polymerase binding site 
A)  methylates the DNA 
B)  demethylates the DNA 
C)  changes the shape of the DNA 
D)  produces signals that attract other transcription factors 
E)  blocks the RNA polymerase binding site

Question 14

Which level is not a potential point of regulation of gene expression?

Accepted Answer

A)  The level of transcription 
B)  The level of processing mRNA 
C)  The level of mRNA stability 
D)  The level of translation 
E)  The level of protein export 
A)  The level of transcription 
B)  The level of processing mRNA 
C)  The level of mRNA stability 
D)  The level of translation 
E)  The level of protein export

Exam 11: Regulation of Gene Expression

Early genes of a lytic bacteriophage are transcribed by

The HIV virus that causes AIDS is a(n)

In which of these pairs do the two entities act in opposite ways?

In comparison with genes in bacterial operons,genes that encode for stress responses in plants

What is a likely advantage of transcriptional regulation over allosteric regulation?

Genomic imprinting

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n)_______ operon and M acts as a(n)_______.

In eukaryotic cells,promoters are

Which statement about viruses is true?

Which statement about operons is false?

What kind of mutation would lead to an increase in the expression (or inappropriate expression)of a gene?

The binding of TFIID to the promoter _______,thereby enabling the binding of other transcription factors.

Which level is not a potential point of regulation of gene expression?

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

DNA and Its Role in Heredity

From Dna to Protein: 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

In the absence of substance M,a hypothetical LM operon is turned off.If substance M is abundant,it can bind to the repressor,which permits the polymerase to begin transcribing the DNA.In this case,LM is a(n)_ operon and M acts as a(n)_.