Question 1

Use the following figure to answer the questions below.
  
-What has happened to make the products C and D?

Accepted Answer

A) frame shift mutation 
B) loss of introns 
C) mRNA degradation 
D) incorrect 5' cap placement 
E) alternative splicing 
A) frame shift mutation 
B) loss of introns 
C) mRNA degradation 
D) incorrect 5' cap placement 
E) alternative splicing

Question 2

Use the following figure to answer the questions below.
  
-What is the significance of C and D?

Accepted Answer

A) One will make a missense protein that will interfere with the other. 
B) They will not survive long enough to undergo translation. 
C) They will compete with each other for substrate. 
D) They will produce two different products from the same mRNA. 
E) There is no significance. 
A) One will make a missense protein that will interfere with the other. 
B) They will not survive long enough to undergo translation. 
C) They will compete with each other for substrate. 
D) They will produce two different products from the same mRNA. 
E) There is no significance.

Question 3

Which of the following seems to account for most of the non-protein-coding DNA?

Accepted Answer

A) "junk" DNA that serves no possible purpose 
B) rRNA and tRNA coding sequences 
C) DNA that is translated directly without being transcribed 
D) non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function 
E) non-protein-coding DNA that is transcribed into several kinds of small RNAs without biological function 
A) "junk" DNA that serves no possible purpose 
B) rRNA and tRNA coding sequences 
C) DNA that is translated directly without being transcribed 
D) non-protein-coding DNA that is transcribed into several kinds of small RNAs with biological function 
E) non-protein-coding DNA that is transcribed into several kinds of small RNAs without biological function

Question 4

Embryonic lethal mutations result in

Accepted Answer

A) phenotypes that prevent fertilization. 
B) failure to express maternal effect genes. 
C) death during infancy. 
D) phenotypes that are never born/hatched. 
E) homeotic phenotype changes. 
A) phenotypes that prevent fertilization. 
B) failure to express maternal effect genes. 
C) death during infancy. 
D) phenotypes that are never born/hatched. 
E) homeotic phenotype changes.

Question 5

Use the following information to answer the questions below.
A researcher introduces double-stranded RNA into a culture of mammalian cells,and can identify its location or that of its smaller subsections experimentally,using a fluorescent probe.
-Some time later,she finds that the introduced strand separates into single-stranded RNAs,one of which is degraded.What does this enable the remaining strand to do?

Accepted Answer

A) attach to histones in the chromatin 
B) bind to complementary regions of target mRNAs 
C) bind to Dicer enzymes to destroy other RNAs 
D) activate other siRNAs in the cell 
E) bind to noncomplementary RNA sequences 
A) attach to histones in the chromatin 
B) bind to complementary regions of target mRNAs 
C) bind to Dicer enzymes to destroy other RNAs 
D) activate other siRNAs in the cell 
E) bind to noncomplementary RNA sequences

Question 6

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 
E) the folding of DNA to form heterochromatin 
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 
E) the folding of DNA to form heterochromatin

Question 7

The role of a metabolite that controls a repressible operon is to

Accepted Answer

A) bind to the promoter region and decrease the affinity of RNA polymerase for the promoter. 
B) bind to the operator region and block the attachment of RNA polymerase to the promoter. 
C) increase the production of inactive repressor proteins. 
D) bind to the repressor protein and inactivate it. 
E) bind to the repressor protein and activate it. 
A) bind to the promoter region and decrease the affinity of RNA polymerase for the promoter. 
B) bind to the operator region and block the attachment of RNA polymerase to the promoter. 
C) increase the production of inactive repressor proteins. 
D) bind to the repressor protein and inactivate it. 
E) bind to the repressor protein and activate it.

Question 8

Use the following information to answer the questions below.
A researcher introduces double-stranded RNA into a culture of mammalian cells,and can identify its location or that of its smaller subsections experimentally,using a fluorescent probe.
-Within the first quarter hour,the researcher sees that the intact RNA is found in the cells.After 3 hours,she is not surprised to find that

Accepted Answer

A) Dicer enzyme has reduced it to smaller double-stranded pieces. 
B) the RNA is degraded by 5' and 3' exonucleases. 
C) the double-stranded RNA replicates itself. 
D) the double-stranded RNA binds to mRNAs to prevent translation. 
E) the double-stranded RNA binds to tRNAs to prevent translation. 
A) Dicer enzyme has reduced it to smaller double-stranded pieces. 
B) the RNA is degraded by 5' and 3' exonucleases. 
C) the double-stranded RNA replicates itself. 
D) the double-stranded RNA binds to mRNAs to prevent translation. 
E) the double-stranded RNA binds to tRNAs to prevent translation.

Question 9

Which of the following genes map out the basic subdivisions along the anterior-posterior axis of the Drosophila embryo?

Accepted Answer

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

Question 10

A mutation that inactivates the regulatory gene of a repressible operon in an E.coli cell would result in

Accepted Answer

A) continuous transcription of the gene controlled by that regulator. 
B) complete inhibition of transcription of the gene controlled by that regulator. 
C) irreversible binding of the repressor to the operator. 
D) inactivation of RNA polymerase by alteration of its active site. 
E) continuous translation of the mRNA because of alteration of its structure. 
A) continuous transcription of the gene controlled by that regulator. 
B) complete inhibition of transcription of the gene controlled by that regulator. 
C) irreversible binding of the repressor to the operator. 
D) inactivation of RNA polymerase by alteration of its active site. 
E) continuous translation of the mRNA because of alteration of its structure.

Question 11

The cancer-causing forms of the Ras protein are involved in which of the following processes?

Accepted Answer

A) relaying a signal from a growth factor receptor 
B) DNA replication 
C) DNA repair 
D) cell-cell adhesion 
E) cell division 
A) relaying a signal from a growth factor receptor 
B) DNA replication 
C) DNA repair 
D) cell-cell adhesion 
E) cell division

Question 12

Genomic imprinting,DNA methylation,and histone acetylation are all examples of

Accepted Answer

A) genetic mutation. 
B) chromosomal rearrangements. 
C) karyotypes. 
D) epigenetic phenomena. 
E) translocation. 
A) genetic mutation. 
B) chromosomal rearrangements. 
C) karyotypes. 
D) epigenetic phenomena. 
E) translocation.

Question 13

Use the following information to answer the questions below.
A researcher has arrived at a method to prevent gene expression from Drosophila embryonic genes.The following questions assume that he is using this method.
-The researcher continues to study the reactions of the embryo to these new proteins and you hypothesize that he is most likely to see which of the following (while embryonic genes are still not being expressed)?

Accepted Answer

A) The cells begin to differentiate. 
B) The proteins are evenly distributed throughout the embryo. 
C) Larval features begin to make their appearance. 
D) Spatial axes (anterior → posterior, etc.)begin to be determined. 
E) The embryo begins to lose cells due to apoptosis from no further gene expression. 
A) The cells begin to differentiate. 
B) The proteins are evenly distributed throughout the embryo. 
C) Larval features begin to make their appearance. 
D) Spatial axes (anterior → posterior, etc.)begin to be determined. 
E) The embryo begins to lose cells due to apoptosis from no further gene expression.

Question 14

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) small intestinal and esophageal 
D) lung only 
E) lung and prostate 
A) colorectal only 
B) lung and breast 
C) small intestinal and esophageal 
D) lung only 
E) lung and prostate

Question 15

In response to chemical signals,prokaryotes can do which of the following?

Accepted Answer

A) turn off translation of their mRNA 
B) alter the level of production of various enzymes 
C) increase the number and responsiveness of their ribosomes 
D) inactivate their mRNA molecules 
E) alter the sequence of amino acids in certain proteins 
A) turn off translation of their mRNA 
B) alter the level of production of various enzymes 
C) increase the number and responsiveness of their ribosomes 
D) inactivate their mRNA molecules 
E) alter the sequence of amino acids in certain proteins

Question 16

What causes different sets of proteins to be expressed in a nerve and a pancreatic cell of the same individual?

Accepted Answer

A) different genes 
B) different regulatory sequences 
C) different sets of regulatory proteins 
D) different promoters 
E) different RNA 
A) different genes 
B) different regulatory sequences 
C) different sets of regulatory proteins 
D) different promoters 
E) different RNA

Question 17

Drosophila larvae (wt)showing segmentation and anterior-posterior axis.
Refer to the image above to answer the following questions.
-The product of the gene responsible for anterior-posterior axis is concentrated more in the anterior end.This supports the

Accepted Answer

A) oncogen gradient hypothesis. 
B) mutagen gradient hypothesis. 
C) morphogen gradient hypothesis. 
D) one gene-one protein hypothesis. 
E) egg-polarity theory. 
A) oncogen gradient hypothesis. 
B) mutagen gradient hypothesis. 
C) morphogen gradient hypothesis. 
D) one gene-one protein hypothesis. 
E) egg-polarity theory.

Question 18

How can one detect alternative splicing of transcripts from a given gene?

Accepted Answer

A) compare the DNA sequence of the given gene to that of a similar gene in a related organism 
B) measure the relative rates of transcription of the given gene compared to that of a gene known to be constitutively spliced 
C) compare the sequences of different primary transcripts made from the given gene 
D) compare the sequences of different mRNAs made from the given gene 
E) measure the amount of mRNA in the nucleus compared to that found in the cytoplasm 
A) compare the DNA sequence of the given gene to that of a similar gene in a related organism 
B) measure the relative rates of transcription of the given gene compared to that of a gene known to be constitutively spliced 
C) compare the sequences of different primary transcripts made from the given gene 
D) compare the sequences of different mRNAs made from the given gene 
E) measure the amount of mRNA in the nucleus compared to that found in the cytoplasm

Question 19

Of the following scenarios for future research,from which would you expect to gain most medical benefit from noncoding RNAs?

Accepted Answer

A) exploring a way to turn on the expression of pseudogenes 
B) targeting siRNAs to disable the expression of an allele associated with autosomal recessive disease 
C) targeting siRNAs to disable the expression of an allele associated with autosomal dominant disease 
D) creating knock-out organisms that can be useful for pharmaceutical drug design 
E) looking for a way to prevent viral DNA from causing infection in humans 
A) exploring a way to turn on the expression of pseudogenes 
B) targeting siRNAs to disable the expression of an allele associated with autosomal recessive disease 
C) targeting siRNAs to disable the expression of an allele associated with autosomal dominant disease 
D) creating knock-out organisms that can be useful for pharmaceutical drug design 
E) looking for a way to prevent viral DNA from causing infection in humans

Question 20

Cell differentiation always involves

Accepted Answer

A) the production of tissue-specific proteins, such as muscle actin. 
B) the movement of cells. 
C) the transcription of the myoD gene. 
D) the selective loss of certain genes from the genome. 
E) the cell's sensitivity to environmental cues, such as light or heat. 
A) the production of tissue-specific proteins, such as muscle actin. 
B) the movement of cells. 
C) the transcription of the myoD gene. 
D) the selective loss of certain genes from the genome. 
E) the cell's sensitivity to environmental cues, such as light or heat.

Exam 18: Regulation of Gene Expression

Use the following figure to answer the questions below. -What has happened to make the products C and D?

Use the following figure to answer the questions below. -What is the significance of C and D?

Which of the following seems to account for most of the non-protein-coding DNA?

Embryonic lethal mutations result in

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

The role of a metabolite that controls a repressible operon is to

Which of the following genes map out the basic subdivisions along the anterior-posterior axis of the Drosophila embryo?

A mutation that inactivates the regulatory gene of a repressible operon in an E.coli cell would result in

The cancer-causing forms of the Ras protein are involved in which of the following processes?

Genomic imprinting,DNA methylation,and histone acetylation are all examples of

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

In response to chemical signals,prokaryotes can do which of the following?

What causes different sets of proteins to be expressed in a nerve and a pancreatic cell of the same individual?

Drosophila larvae (wt)showing segmentation and anterior-posterior axis. Refer to the image above to answer the following questions. -The product of the gene responsible for anterior-posterior axis is concentrated more in the anterior end.This supports the

How can one detect alternative splicing of transcripts from a given gene?

Of the following scenarios for future research,from which would you expect to gain most medical benefit from noncoding RNAs?

Cell differentiation always involves

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

The Molecular Basis of Inheritance

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 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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