Question 1

The fact that plants can be cloned from somatic cells demonstrates that ________.

Accepted Answer

A)  differentiated cells retain all the genes of the zygote 
B)  genes are lost during differentiation 
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)  genes are lost during differentiation 
C)  the differentiated state is normally very unstable 
D)  differentiation does not occur in plants A

Question 2

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

Accepted Answer

A)  CRP binds cAMP 
B)  CRP binds to the CAP-binding site 
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 binds cAMP 
B)  CRP binds to the CAP-binding site 
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 D

Question 3

Mutations in which of the following genes lead to transformations in the identity of entire body parts?

Accepted Answer

A)  segmentation genes 
B)  egg-polarity genes 
C)  homeotic genes 
D)  inducers 
A)  segmentation genes 
B)  egg-polarity genes 
C)  homeotic genes 
D)  inducers C

Question 4

Which of the following methods is utilised by eukaryotes to control their gene expression that is different from the type of control found in bacteria?

Accepted Answer

A)  control of chromatin remodelling 
B)  control of RNA splicing 
C)  transcriptional control 
D)  control of both RNA splicing and chromatin remodelling 
A)  control of chromatin remodelling 
B)  control of RNA splicing 
C)  transcriptional control 
D)  control of both RNA splicing and chromatin remodelling

Question 5

Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If a researcher moves the repressor gene (lacI), along with its promoter, to a position at some several thousand base pairs away from its normal position, which of the following results would be expected?

Accepted Answer

A)  The repressor will no longer bind to the operator. 
B)  The repressor will no longer bind to the inducer. 
C)  The lac operon will be expressed continuously. 
D)  The lac operon will function normally. 
A)  The repressor will no longer bind to the operator. 
B)  The repressor will no longer bind to the inducer. 
C)  The lac operon will be expressed continuously. 
D)  The lac operon will function normally.

Question 6

How are bacteria able to change their patterns of protein synthesis so quickly in response to environmental changes?

Accepted Answer

A)  mRNAs that are produced are short-lived and degraded within a few minutes of being synthesised. 
B)  mRNA have long lifespans, allowing the bacteria to use them many times for translation. 
C)  mRNA is stored for later use. 
D)  Operons are activated in the presence of transcription factors. 
A)  mRNAs that are produced are short-lived and degraded within a few minutes of being synthesised. 
B)  mRNA have long lifespans, allowing the bacteria to use them many times for translation. 
C)  mRNA is stored for later use. 
D)  Operons are activated in the presence of transcription factors.

Question 7

What would be the result of a mutation in a maternal effect gene in a female Drosophila?

Accepted Answer

A)  She will not develop past the early embryonic stage. 
B)  All of her offspring will show the mutant phenotype, regardless of their genotype. 
C)  Only her male offspring will show the mutant phenotype. 
D)  Only her female offspring will show the mutant phenotype. 
A)  She will not develop past the early embryonic stage. 
B)  All of her offspring will show the mutant phenotype, regardless of their genotype. 
C)  Only her male offspring will show the mutant phenotype. 
D)  Only her female offspring will show the mutant phenotype.

Question 8

The bicoid gene product is normally localised to the anterior end of the embryo. If large amounts of the product were injected into the posterior end as well, which of the following developmental events would occur?

Accepted Answer

A)  The embryo would grow extra wings and legs. 
B)  The embryo would probably show no anterior development and die. 
C)  Anterior structures would form in both ends of the embryo. 
D)  The embryo would develop normally. 
A)  The embryo would grow extra wings and legs. 
B)  The embryo would probably show no anterior development and die. 
C)  Anterior structures would form in both ends of the embryo. 
D)  The embryo would develop normally.

Question 9

Which of the following molecules are involved in pattern formation during development?

Accepted Answer

A)  cytoplasmic determinants 
B)  miRNAs 
C)  cAMP 
D)  transcription factors 
A)  cytoplasmic determinants 
B)  miRNAs 
C)  cAMP 
D)  transcription factors

Question 10

Which of the following statements describes a cell that is considered to be differentiated?

Accepted Answer

A)  The cell replicates by the process of mitosis. 
B)  The cell loses connections to the surrounding cells. 
C)  The cell produces proteins specific to a particular cell type. 
D)  The cell appears to be different from the surrounding cells. 
A)  The cell replicates by the process of mitosis. 
B)  The cell loses connections to the surrounding cells. 
C)  The cell produces proteins specific to a particular cell type. 
D)  The cell appears to be different from the surrounding cells.

Question 11

In colorectal cancer, several genes must be mutated for a cell to develop into a cancer cell. Which of the following kinds of genes would you expect to be mutated?

Accepted Answer

A)  genes coding for enzymes that act in the colon 
B)  genes involved in control of the cell cycle 
C)  genes that are especially susceptible to mutation 
D)  genes of the bacteria, which are abundant in the colon 
A)  genes coding for enzymes that act in the colon 
B)  genes involved in control of the cell cycle 
C)  genes that are especially susceptible to mutation 
D)  genes of the bacteria, which are abundant in the colon

Question 12

Which of the following types of mutation would convert a proto-oncogene into an oncogene?

Accepted Answer

A)  A mutation that blocks transcription of the proto-oncogene. 
B)  A mutation that creates an unstable proto-oncogene mRNA. 
C)  A mutation that greatly increases the amount of the proto-oncogene protein. 
D)  A deletion of most of the proto-oncogene coding sequence. 
A)  A mutation that blocks transcription of the proto-oncogene. 
B)  A mutation that creates an unstable proto-oncogene mRNA. 
C)  A mutation that greatly increases the amount of the proto-oncogene protein. 
D)  A deletion of most of the proto-oncogene coding sequence.

Question 13

Which of the following processes would result from a mutation that deactivates a regulatory gene of a repressible operon in an E. coli cell?

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 14

Which of the following mechanisms is used to coordinate the expression of multiple, related genes in eukaryotic cells?

Accepted Answer

A)  Environmental signals enter the cell and bind directly to promoters. 
B)  A given gene may have multiple enhancers, but each enhancer is generally associated with only that gene and no other. 
C)  The genes are organised into a large operon, allowing them to be coordinately controlled as a single unit. 
D)  A single repressor is able to turn off several related genes. 
A)  Environmental signals enter the cell and bind directly to promoters. 
B)  A given gene may have multiple enhancers, but each enhancer is generally associated with only that gene and no other. 
C)  The genes are organised into a large operon, allowing them to be coordinately controlled as a single unit. 
D)  A single repressor is able to turn off several related genes.

Question 15

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.

Question 16

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

Accepted Answer

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

Question 17

Which of the following is an example of post-transcriptional control of gene expression?

Accepted Answer

A)  the addition of methyl groups to cytosine bases of DNA 
B)  the binding of transcription factors to a promoter 
C)  the removal of introns and alternative splicing of exons 
D)  gene amplification contributing to cancer 
A)  the addition of methyl groups to cytosine bases of DNA 
B)  the binding of transcription factors to a promoter 
C)  the removal of introns and alternative splicing of exons 
D)  gene amplification contributing to cancer

Question 18

Why are BRCA1 and BRCA2 considered to be tumour-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 make oestrogen 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 make oestrogen receptors. 
D)  They block penetration of breast cells by chemical carcinogens.

Question 19

Which of the following processes do normal proto-oncogenes typically exhibit?

Accepted Answer

A)  They normally suppress tumour growth. 
B)  They enhance tumour growth. 
C)  They stimulate normal cell growth and division. 
D)  They are under expressed in cancer cells. 
A)  They normally suppress tumour growth. 
B)  They enhance tumour growth. 
C)  They stimulate normal cell growth and division. 
D)  They are under expressed in cancer cells.

Question 20

At the beginning of this century, there was a general announcement regarding the sequencing of the human genome and the genomes of many other multicellular eukaryotes. Many people were surprised that the number of protein-coding sequences was much smaller than they had expected. Which of the following types of DNA make up the rest of the human genome?

Accepted Answer

A)  DNA that consists of histone coding sequences 
B)  DNA that is translated directly without being transcribed 
C)  non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function 
D)  non-protein-coding DNA that serves as binding sites for reverse transcriptase 
A)  DNA that consists of histone coding sequences 
B)  DNA that is translated directly without being transcribed 
C)  non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function 
D)  non-protein-coding DNA that serves as binding sites for reverse transcriptase

Exam 18: Regulation of Gene Expression

The fact that plants can be cloned from somatic cells demonstrates that ________.

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

Mutations in which of the following genes lead to transformations in the identity of entire body parts?

Which of the following methods is utilised by eukaryotes to control their gene expression that is different from the type of control found in bacteria?

How are bacteria able to change their patterns of protein synthesis so quickly in response to environmental changes?

What would be the result of a mutation in a maternal effect gene in a female Drosophila?

The bicoid gene product is normally localised to the anterior end of the embryo. If large amounts of the product were injected into the posterior end as well, which of the following developmental events would occur?

Which of the following molecules are involved in pattern formation during development?

Which of the following statements describes a cell that is considered to be differentiated?

In colorectal cancer, several genes must be mutated for a cell to develop into a cancer cell. Which of the following kinds of genes would you expect to be mutated?

Which of the following types of mutation would convert a proto-oncogene into an oncogene?

Which of the following processes would result from a mutation that deactivates a regulatory gene of a repressible operon in an E. coli cell?

Which of the following mechanisms is used to coordinate the expression of multiple, related genes in eukaryotic cells?

The functioning of enhancers is an example of

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

Which of the following is an example of post-transcriptional control of gene expression?

Why are BRCA1 and BRCA2 considered to be tumour-suppressor genes?

Which of the following processes do normal proto-oncogenes typically exhibit?

Evolution, the Themes of Biology, and Scientific Inquiry

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

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

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 Colonised 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

Vascular 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

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