Question 1

Inducible genes are usually actively transcribed when:

Accepted Answer

A)  an inducer inactivates the repressor. 
B)  repressor molecules bind to the promoter. 
C)  lactose is absent from the cell. 
D)  expression of repressor genes is turned off. 
E)  energy is not needed by the cell. 
A)  an inducer inactivates the repressor. 
B)  repressor molecules bind to the promoter. 
C)  lactose is absent from the cell. 
D)  expression of repressor genes is turned off. 
E)  energy is not needed by the cell.

Question 2

In Jacob and Monad's analysis of mutant E. coli strains in their study of the lac operon, the absence of the β -galactosidase enzyme, but presence of the lactose permease and galactosidase transacetylase enzymes, indicated that the mutation occurred in the _____ of the lac operon.

Accepted Answer

A)  regulatory region 
B)  lacZ gene 
C)  lacA gene 
D)  lacY gene 
E)  heterochromatin 
A)  regulatory region 
B)  lacZ gene 
C)  lacA gene 
D)  lacY gene 
E)  heterochromatin

Question 3

Identify two ways in which posttranscriptional gene regulation occurs in eukaryotes and briefly explain each.

Accepted Answer

The addition of a poly- A- tail to eukar

Question 4

A new operon is discovered in bacteria. Transcription of the genes in this operon is blocked by the binding of a protein to DNA sequences upstream of the operon. This is an example of ____ control.

Accepted Answer

A)  positive 
B)  negative 
C)  constitutive 
D)  posttranscriptional 
E)  inducible 
A)  positive 
B)  negative 
C)  constitutive 
D)  posttranscriptional 
E)  inducible

Question 5

Why is it important that a few β -galactosidase molecules be present in E. coli even if these cells have been growing on a lactose-free medium?

Accepted Answer

It is important so that when l

Question 6

In the lac operon, cAMP binds to:

Accepted Answer

A)  lacZ. 
B)  lacA . 
C)  lacY . 
D)  the operator. 
E)  CAP. 
A)  lacZ. 
B)  lacA . 
C)  lacY . 
D)  the operator. 
E)  CAP.

Question 7

Constitutive genes code for proteins that are needed for survival. 
__________________

Accepted Answer

A) True 
 B)False

Question 8

cAMP levels decrease when __________. This results in __________ of CAP.

Accepted Answer

A)  lactose levels increase; activation 
B)  lactose levels decrease; inhibition 
C)  glucose levels increase; inhibition 
D)  glucose levels decrease; activation 
E)  glucose levels decrease; inhibition 
A)  lactose levels increase; activation 
B)  lactose levels decrease; inhibition 
C)  glucose levels increase; inhibition 
D)  glucose levels decrease; activation 
E)  glucose levels decrease; inhibition

Question 9

Explain the respective advantages associated with operons being inducible (e.g., the lactose operon) or repressible (e.g., the tryptophan operon).

Accepted Answer

Inducible operons save energy for the pr

Question 10

Proteolytic processing, chemical modification, and protein degradation are all methods of posttranslational regulation mechanism.

Accepted Answer

A) True 
 B)False

Question 11

Translational controls of protein levels in bacteria are governed by the:

Accepted Answer

A)  rate at which small and large subunits of ribosomes assemble. 
B)  rate at which the cap and tail of pre mRNA are removed. 
C)  rate at which ribosomes attach to mRNA molecules. 
D)  concentration of proteins in the cytoplasm. 
E)  rate at which sugars are incorporated into the cell. 
A)  rate at which small and large subunits of ribosomes assemble. 
B)  rate at which the cap and tail of pre mRNA are removed. 
C)  rate at which ribosomes attach to mRNA molecules. 
D)  concentration of proteins in the cytoplasm. 
E)  rate at which sugars are incorporated into the cell.

Question 12

Repressible genes typically regulate gene expression of enzymes involved in anabolic pathways. 
__________________

Accepted Answer

A) True 
 B)False

Question 13

Long coding RNAs (lnc RNAs) are characterized by:

Accepted Answer

A)  the presence of introns. 
B)  the lack of a polyA tail. 
C)  their roles in regulating transcription. 
D)  being less than 100 bases in length. 
E)  binding to zinc finger transcription factors. 
A)  the presence of introns. 
B)  the lack of a polyA tail. 
C)  their roles in regulating transcription. 
D)  being less than 100 bases in length. 
E)  binding to zinc finger transcription factors.

Question 14

Enzymes that alter another protein or enzyme's activity by attaching a phosphate group are called:

Accepted Answer

A)  kinases. 
B)  phosphatases. 
C)  phosphators. 
D)  transcription factors. 
E)  coenzymes. 
A)  kinases. 
B)  phosphatases. 
C)  phosphators. 
D)  transcription factors. 
E)  coenzymes.

Question 15

Leucine zipper proteins regulate transcription by:

Accepted Answer

A)  forming dimers with zinc finger transcription factors. 
B)  changing the chromatin structure to heterochromatin 
C)  blocking DNA regulatory elements. 
D)  binding to and activating DNA regulatory elements such as enhancers and silencers. 
E)  degrading RNA polymerase. 
A)  forming dimers with zinc finger transcription factors. 
B)  changing the chromatin structure to heterochromatin 
C)  blocking DNA regulatory elements. 
D)  binding to and activating DNA regulatory elements such as enhancers and silencers. 
E)  degrading RNA polymerase.

Question 16

A cell may meet the demand for large quantities of a specific protein by:

Accepted Answer

A)  blocking transcription of the gene that encodes the protein. 
B)  decreasing the half-life of the mRNA that specifies the protein. 
C)  adding methyl groups to the gene that encodes the protein. 
D)  gene amplification 
E)  inhibition of DNA synthesis 
A)  blocking transcription of the gene that encodes the protein. 
B)  decreasing the half-life of the mRNA that specifies the protein. 
C)  adding methyl groups to the gene that encodes the protein. 
D)  gene amplification 
E)  inhibition of DNA synthesis

Question 17

The rate of eukaryotic transcription after initiation is increased by:

Accepted Answer

A)  upstream promoter elements. 
B)  the order of gene arrangement in operons. 
C)  the action of catabolite activator proteins. 
D)  how fast 5' caps and 3' tails can be added to pre-mRNA. 
E)  enhancers. 
A)  upstream promoter elements. 
B)  the order of gene arrangement in operons. 
C)  the action of catabolite activator proteins. 
D)  how fast 5' caps and 3' tails can be added to pre-mRNA. 
E)  enhancers.

Exam 14: Gene Regulation

Inducible genes are usually actively transcribed when:

In Jacob and Monad's analysis of mutant E. coli strains in their study of the lac operon, the absence of the β -galactosidase enzyme, but presence of the lactose permease and galactosidase transacetylase enzymes, indicated that the mutation occurred in the _____ of the lac operon.

Identify two ways in which posttranscriptional gene regulation occurs in eukaryotes and briefly explain each.

A new operon is discovered in bacteria. Transcription of the genes in this operon is blocked by the binding of a protein to DNA sequences upstream of the operon. This is an example of ____ control.

Why is it important that a few β -galactosidase molecules be present in E. coli even if these cells have been growing on a lactose-free medium?

In the lac operon, cAMP binds to:

Constitutive genes code for proteins that are needed for survival. __________________

cAMP levels decrease when __________. This results in __________ of CAP.

Explain the respective advantages associated with operons being inducible (e.g., the lactose operon) or repressible (e.g., the tryptophan operon).

Proteolytic processing, chemical modification, and protein degradation are all methods of posttranslational regulation mechanism.

Translational controls of protein levels in bacteria are governed by the:

Repressible genes typically regulate gene expression of enzymes involved in anabolic pathways. __________________

Long coding RNAs (lnc RNAs) are characterized by:

Enzymes that alter another protein or enzyme's activity by attaching a phosphate group are called:

Leucine zipper proteins regulate transcription by:

A cell may meet the demand for large quantities of a specific protein by:

The rate of eukaryotic transcription after initiation is increased by:

A View of Life

Atoms and Molecules the Chemical Basis of Life

The Chemistry of Life Organic Compounds

Organization of the Cell

Biological Membranes

Cell Communication

Energy and Metabolism

How Cells Make Atp Energy-Releasing Pathways

Photosynthesis Capturing Light Energy

Chromosomes, Mitosis, and Meiosis

The Basic Principles of Heredity

Dna the Carrier of Genetic Information

Gene Expression

Dna Technology and Genomics

Human Genetics and the Human Genome

Developmental Genetics

Introduction to Darwinian Evolution

Evolutionary Change in Populations

Speciation and Macroevolution

The Origin and Evolutionary History of Life

The Evolution of Primates

Understanding Diversity Systematics

Viruses and Subviral Agents

Bacteria and Archaea

Protists

Seedless Plants

Seed Plants

The Fungi

An Introduction to Animal Diversity

Sponges, Cnidarians, Ctenophores, and Protostomes

The Deuterostomes

Plant Structure Growth and Development

Leaf Structure and Function

Stem Structure and Transport

Roots and Mineral Nutrition

Reproduction in Flowering Plants

Plant Developmental Responses to External and Internal Signals

Animal Structure and Function an Introduction

Protection Support and Movement

Neural Signaling

Neural Regulation

Sensory Systems

Internal Transport

The Immune System Internal Defense

Gas Exchange

Processing Food and Nutrition

Osmoregulation and Disposal of Metabolic Wastes

Endocrine Regulation

Reproduction

Animal Development

Animal Behavior

Introduction to Ecology Population Ecology

Community Ecology

Ecosystems and the Biosphere

Ecology and the Geography of Life

Biological Diversity and Conservation Biology

Filters

cAMP levels decrease when . This results in of CAP.