Question 1

Assays analyzing transcriptional control of gene expression focus on which of the following characteristics?

Accepted Answer

A)  number of copies of the gene in the organism 
B)  size of the gene's open reading frame 
C)  relative level of the protein produced 
D)  amount of the mRNA generated 
A)  number of copies of the gene in the organism 
B)  size of the gene's open reading frame 
C)  relative level of the protein produced 
D)  amount of the mRNA generated D

Question 2

The functioning of enhancers is an example of ________.

Accepted Answer

A)  a eukaryotic equivalent of prokaryotic promoter functioning 
B)  transcriptional control of gene expression 
C)  the stimulation of translation by initiation factors 
D)  post-translational control that activates certain proteins 
A)  a eukaryotic equivalent of prokaryotic promoter functioning 
B)  transcriptional control of gene expression 
C)  the stimulation of translation by initiation factors 
D)  post-translational control that activates certain proteins B

Question 3

A genetic test to detect predisposition to cancer would likely examine the APC gene for involvement in which type(s) of cancer?

Accepted Answer

A)  colorectal only 
B)  lung and breast 
C)  lung only 
D)  lung and prostate 
A)  colorectal only 
B)  lung and breast 
C)  lung only 
D)  lung and prostate A

Question 4

If a mutation deactivated a regulatory gene of a repressible operon in an E. coli cell which of the following describes the most likely outcome?

Accepted Answer

A)  continuous transcription of the structural gene controlled by that regulator 
B)  complete inhibition of transcription of the structural gene controlled by that regulator 
C)  irreversible binding of the repressor to the operator 
D)  continuous translation of the mRNA because of alteration of its structure 
A)  continuous transcription of the structural gene controlled by that regulator 
B)  complete inhibition of transcription of the structural gene controlled by that regulator 
C)  irreversible binding of the repressor to the operator 
D)  continuous translation of the mRNA because of alteration of its structure

Question 5

According to the lac operon model proposed by Jacob and Monod, what is predicted to occur if the operator is removed from the operon?

Accepted Answer

A)  The lac operon would be transcribed continuously. 
B)  Only lacZ would be transcribed. 
C)  Only lacY would be transcribed. 
D)  Genes involved in glucose metabolism would not be transcribed. 
A)  The lac operon would be transcribed continuously. 
B)  Only lacZ would be transcribed. 
C)  Only lacY would be transcribed. 
D)  Genes involved in glucose metabolism would not be transcribed.

Question 6

Under which condition do high levels of transcription of structural genes occur in an inducible operon?

Accepted Answer

A)  It occurs continuously in the cell. 
B)  It starts when the pathway's substrate is present. 
C)  It starts when the pathway's product is present. 
D)  It stops when the pathway's product is present. 
A)  It occurs continuously in the cell. 
B)  It starts when the pathway's substrate is present. 
C)  It starts when the pathway's product is present. 
D)  It stops when the pathway's product is present.

Question 7

The cAMP receptor protein (CRP) is said to be responsible for positive regulation of the lac operon because ________.

Accepted Answer

A)  CRP levels rise when lactose is present in the environment 
B)  CRP promotes the production of allolactose 
C)  CRP prevents binding of the repressor to the operator 
D)  CRP bound to the CRP-binding site stimulates the transcription of the lac operon 
A)  CRP levels rise when lactose is present in the environment 
B)  CRP promotes the production of allolactose 
C)  CRP prevents binding of the repressor to the operator 
D)  CRP bound to the CRP-binding site stimulates the transcription of the lac operon

Question 8

Absence of bicoid mRNA from a Drosophila egg leads to the absence of anterior larval body parts and mirror-image duplication of posterior parts. This is evidence that the product of the bicoid gene ________.

Accepted Answer

A)  normally leads to formation of head structures 
B)  normally leads to formation of tail structures 
C)  is transcribed in the early embryo 
D)  is a protein present in all head structures 
A)  normally leads to formation of head structures 
B)  normally leads to formation of tail structures 
C)  is transcribed in the early embryo 
D)  is a protein present in all head structures

Question 9

Within a cell, the amount of protein made using a given mRNA molecule in that cell depends partly on ________.

Accepted Answer

A)  the degree of DNA methylation 
B)  the rate at which the mRNA is degraded 
C)  the number of introns present in the mRNA 
D)  the types of ribosomes present in the cytoplasm 
A)  the degree of DNA methylation 
B)  the rate at which the mRNA is degraded 
C)  the number of introns present in the mRNA 
D)  the types of ribosomes present in the cytoplasm

Question 10

If a researcher moves the operator to the far end of the operon, which of the following processes would likely occur when the cell is exposed to lactose?

Accepted Answer

A)  The inducer will no longer bind to the repressor. 
B)  The repressor will no longer bind to the operator. 
C)  The operon will never be transcribed. 
D)  The genes of the lac operon will be transcribed continuously. 
A)  The inducer will no longer bind to the repressor. 
B)  The repressor will no longer bind to the operator. 
C)  The operon will never be transcribed. 
D)  The genes of the lac operon will be transcribed continuously.

Question 11

Cell differentiation always involves ________.

Accepted Answer

A)  transcription of the myoD gene 
B)  the movement of cells 
C)  the production of tissue-specific proteins 
D)  the selective loss of certain genes from the genome 
A)  transcription of the myoD gene 
B)  the movement of cells 
C)  the production of tissue-specific proteins 
D)  the selective loss of certain genes from the genome

Question 12

Which of the following conditions is most likely to result in transcription of the lac operon?

Accepted Answer

A)  There is more glucose in the cell than lactose. 
B)  There is glucose but no lactose in the cell. 
C)  The cAMP and lactose levels are both high within the cell. 
D)  The cAMP level is high and the lactose level is low. 
A)  There is more glucose in the cell than lactose. 
B)  There is glucose but no lactose in the cell. 
C)  The cAMP and lactose levels are both high within the cell. 
D)  The cAMP level is high and the lactose level is low.

Question 13

Which of the following methods are used by eukaryotes to control gene expression but are not used by bacteria?

Accepted Answer

A)  organization of genes in operons 
B)  limiting access to free nucleic acids 
C)  regulatory proteins binding to promoter sequences and determining polymerase used 
D)  control of both RNA splicing and chromatin remodeling 
A)  organization of genes in operons 
B)  limiting access to free nucleic acids 
C)  regulatory proteins binding to promoter sequences and determining polymerase used 
D)  control of both RNA splicing and chromatin remodeling

Question 14

Which of the following characterizes BRCA1 and BRCA2 as tumor-suppressor genes?

Accepted Answer

A)  Their normal products participate in repair of DNA damage. 
B)  The mutant forms of either one of these prevent breast cancer. 
C)  The normal genes code for estrogen receptors. 
D)  They block penetration of breast cells by chemical carcinogens. 
A)  Their normal products participate in repair of DNA damage. 
B)  The mutant forms of either one of these prevent breast cancer. 
C)  The normal genes code for estrogen receptors. 
D)  They block penetration of breast cells by chemical carcinogens.

Question 15

Which of the following molecules binds with a repressor to alter its conformation and therefore affect its function?

Accepted Answer

A)  inducer 
B)  promoter 
C)  transcription factor 
D)  cAMP 
A)  inducer 
B)  promoter 
C)  transcription factor 
D)  cAMP

Question 16

Which of the following best explains why a neuron and a pancreatic cell isolated from the same individual contain different sets of proteins?

Accepted Answer

A)  The set of genes in each cell type are different, therefore, they express different proteins. 
B)  Each cell type needs different proteins and, therefore, they break down proteins they don't need. 
C)  Each cell type contains different regulatory proteins and, therefore, they express different proteins. 
D)  The genes in each cell type have different promoters and, therefore, they respond to different regulatory proteins. 
A)  The set of genes in each cell type are different, therefore, they express different proteins. 
B)  Each cell type needs different proteins and, therefore, they break down proteins they don't need. 
C)  Each cell type contains different regulatory proteins and, therefore, they express different proteins. 
D)  The genes in each cell type have different promoters and, therefore, they respond to different regulatory proteins.

Question 17

Which of the following changes in conditions results in an increase in cAMP receptor protein (CRP) mediated initiation of transcription?

Accepted Answer

A)  an increase in glucose and an increase in the repressor 
B)  a decrease in glucose and an increase in cAMP 
C)  an increase in glucose and a decrease in cAMP 
D)  a decrease in glucose and a decrease in the repressor 
A)  an increase in glucose and an increase in the repressor 
B)  a decrease in glucose and an increase in cAMP 
C)  an increase in glucose and a decrease in cAMP 
D)  a decrease in glucose and a decrease in the repressor

Question 18

Which of the following statements best describes the characteristics of siRNA?

Accepted Answer

A)  a double-stranded RNA, one of whose strands can complement and inactivate a sequence of mRNA 
B)  a single-stranded RNA that can fold into cloverleaf patterns due to regions of internal complementary base pairs 
C)  a double-stranded RNA that is formed by cleavage of hairpin loops in a larger precursor 
D)  a portion of rRNA that allows it to bind to several ribosomal proteins in forming large or small subunits 
A)  a double-stranded RNA, one of whose strands can complement and inactivate a sequence of mRNA 
B)  a single-stranded RNA that can fold into cloverleaf patterns due to regions of internal complementary base pairs 
C)  a double-stranded RNA that is formed by cleavage of hairpin loops in a larger precursor 
D)  a portion of rRNA that allows it to bind to several ribosomal proteins in forming large or small subunits

Question 19

Which of the following conclusions is consistent with the fact that plants can be cloned from somatic cells?

Accepted Answer

A)  Differentiated cells retain all the genes of the zygote. 
B)  Differentiation results in the loss of non-expressed genes. 
C)  The differentiated state is normally very unstable. 
D)  Differentiation does not occur in plants. 
A)  Differentiated cells retain all the genes of the zygote. 
B)  Differentiation results in the loss of non-expressed genes. 
C)  The differentiated state is normally very unstable. 
D)  Differentiation does not occur in plants.

Question 20

When taken up by a cell, which of the following molecules binds to a repressor so that the repressor no longer binds to an operator?

Accepted Answer

A)  inducer 
B)  promoter 
C)  cAMP 
D)  corepressor 
A)  inducer 
B)  promoter 
C)  cAMP 
D)  corepressor

Exam 18: Control of Gene Expression

Assays analyzing transcriptional control of gene expression focus on which of the following characteristics?

The functioning of enhancers is an example of ________.

A genetic test to detect predisposition to cancer would likely examine the APC gene for involvement in which type(s) of cancer?

If a mutation deactivated a regulatory gene of a repressible operon in an E. coli cell which of the following describes the most likely outcome?

According to the lac operon model proposed by Jacob and Monod, what is predicted to occur if the operator is removed from the operon?

Under which condition do high levels of transcription of structural genes occur in an inducible operon?

The cAMP receptor protein (CRP) is said to be responsible for positive regulation of the lac operon because ________.

Absence of bicoid mRNA from a Drosophila egg leads to the absence of anterior larval body parts and mirror-image duplication of posterior parts. This is evidence that the product of the bicoid gene ________.

Within a cell, the amount of protein made using a given mRNA molecule in that cell depends partly on ________.

If a researcher moves the operator to the far end of the operon, which of the following processes would likely occur when the cell is exposed to lactose?

Cell differentiation always involves ________.

Which of the following conditions is most likely to result in transcription of the lac operon?

Which of the following methods are used by eukaryotes to control gene expression but are not used by bacteria?

Which of the following characterizes BRCA1 and BRCA2 as tumor-suppressor genes?

Which of the following molecules binds with a repressor to alter its conformation and therefore affect its function?

Which of the following best explains why a neuron and a pancreatic cell isolated from the same individual contain different sets of proteins?

Which of the following changes in conditions results in an increase in cAMP receptor protein (CRP) mediated initiation of transcription?

Which of the following statements best describes the characteristics of siRNA?

Which of the following conclusions is consistent with the fact that plants can be cloned from somatic cells?

When taken up by a cell, which of the following molecules binds to a repressor so that the repressor no longer binds to an operator?

Biology and Its Themes

Atoms and Molecules

The Chemistry of Water

Carbon: the Basis of Molecular Diversity

Biological Macromolecules and Lipids

Energy and Life

Cell Structure and Function

Cell Membranes

Cellular Signaling

Cell Respiration

Photosynthetic Processes

Mitosis

Sexual Life Cycles and Meiosis

Mendelian Genetics

Linkage and Chromosomes

Nucleic Acids and Inheritance

Expression of Genes

Dna Technology

The Evolution of Genomes

How Evolution Works

Phylogenetic Reconstruction

Microevolution

Species and Speciation

Macroevolution

Introduction to Viruses

Prokaryotes

The Origin and Evolution of Eukaryotes

Nonvascular and Seedless Vascular Plants

Seed Plants

Introduction to Fungi

An Introduction to Animal Diversity

Invertebrates

Vertebrates

Plant Structure and Growth

Transport in Vascular Plants

Plant Nutrition

Reproduction of Flowering Plants

Plant Signals and Behavior

The Animal Body

Chemical Signals in Animals

Animal Digestive Systems

Animal Transport Systems

Animal Excretory Systems

Animal Reproductive Systems

Development in Animals

Animal Defenses Against Infection

Electrical Signals in Animals

Neural Regulation in Animals

Sensation and Movement in Animals

An Overview of Ecology

Behavioral Ecology

Populations and Life History Traits

Biodiversity and Communities

Energy Flow and Chemical Cycling in Ecosystems

Conservation and Global Ecology

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