Question 1

Why is the analysis of transcriptomes useful for genetics research?

Accepted Answer

A) It reveals many aspects of gene regulation. 
B) It is easy to do. 
C) It can help discover non-transcribed DNA regions. 
D) It directly identifies transcription factor binding sites. 
A) It reveals many aspects of gene regulation. 
B) It is easy to do. 
C) It can help discover non-transcribed DNA regions. 
D) It directly identifies transcription factor binding sites.

Question 2

Small RNAs can regulate gene expression by

Accepted Answer

A) binding of target RNAs and inhibiting translation. 
B) binding of rho and preventing termination. 
C) binding of target promoter regions and preventing transcription. 
D) binding of target operator regions and preventing transcription. 
A) binding of target RNAs and inhibiting translation. 
B) binding of rho and preventing termination. 
C) binding of target promoter regions and preventing transcription. 
D) binding of target operator regions and preventing transcription.

Question 3

Fifteen strains of bacteria that are auxotrophic for maltose do not complement each other.The mutations in these bacteria map to the same DNA region using transformatin of random fragments of genomic DNA.There are only two unique enzymes in the maltose biosynthetic pathway and all of the mutants have a mutation in the reading frame for one or the other .What does this data suggest?

Accepted Answer

A) There are lots of enzymes in maltose metabolism. 
B) All the genes for maltose metabolism are in a cluster and could be one operon. 
C) There are genes scattered all over, we've simply found one set of mutants. 
D) Maltose transport is very complex, these are transport mutants. 
A) There are lots of enzymes in maltose metabolism. 
B) All the genes for maltose metabolism are in a cluster and could be one operon. 
C) There are genes scattered all over, we've simply found one set of mutants. 
D) Maltose transport is very complex, these are transport mutants.

Question 4

Catabolic pathways that break down complex substances into more usable units are usually regulated by the

Accepted Answer

A) end products of the pathway. 
B) the levels of the molecule that is to be broken down. 
C) other metabolites that are limiting. 
D) other enzyme binding.. 
A) end products of the pathway. 
B) the levels of the molecule that is to be broken down. 
C) other metabolites that are limiting. 
D) other enzyme binding..

Question 5

How does tryptophan, the end product of the trp operon, function in the regulation of the operon?

Accepted Answer

A) It binds to the repressor preventing it from binding to DNA thus allowing transcription of the operon. 
B) It binds to the repressor and only then can the repressor bind to DNA allowing transcription of the operon. 
C) It binds directly to DNA and inhibits transcription of the operon. 
D) It binds to the repressor and only then can this complex bind to DNA preventing transcription of the operon. 
A) It binds to the repressor preventing it from binding to DNA thus allowing transcription of the operon. 
B) It binds to the repressor and only then can the repressor bind to DNA allowing transcription of the operon. 
C) It binds directly to DNA and inhibits transcription of the operon. 
D) It binds to the repressor and only then can this complex bind to DNA preventing transcription of the operon.

Question 6

As a general principle of gene regulation through operons, regulatory genes encode

Accepted Answer

A) trans-acting proteins that interact with cis-acting DNA elements. 
B) cis-acting proteins that interact with cis-acting DNA elements. 
C) cis-acting proteins that interact with trans-acting DNA elements. 
D) trans-acting proteins that interact with trans-acting DNA elements. 
A) trans-acting proteins that interact with cis-acting DNA elements. 
B) cis-acting proteins that interact with cis-acting DNA elements. 
C) cis-acting proteins that interact with trans-acting DNA elements. 
D) trans-acting proteins that interact with trans-acting DNA elements.

Question 7

How is glucose involved in the catabolite repression of the lactose operon?

Accepted Answer

A) It has nothing to do with regulation of the lactose operon. 
B) It results in decreased cAMP levels, which in turn leads to decreased CRP binding; thus the lac operon is repressed even if lactose is present along with the glucose. 
C) It is also a substrate for $\beta$-galactosidase and thus competes with lactose for this enzyme. 
D) Its presence in the cell increases the amount of lac repressor in the cell. 
A) It has nothing to do with regulation of the lactose operon. 
B) It results in decreased cAMP levels, which in turn leads to decreased CRP binding; thus the lac operon is repressed even if lactose is present along with the glucose. 
C) It is also a substrate for $\beta$-galactosidase and thus competes with lactose for this enzyme. 
D) Its presence in the cell increases the amount of lac repressor in the cell.

Question 8

Alterations to DNA sites such as promoters and operators can act

Accepted Answer

A) only in cis. 
B) only in trans. 
C) either in trans or in cis. 
D) these terms do not apply to regulation. 
A) only in cis. 
B) only in trans. 
C) either in trans or in cis. 
D) these terms do not apply to regulation.

Question 9

Transcription and translation can be coupled in bacteria but not eukaryotes since

Accepted Answer

A) there is no nuclear membrane in prokaryotes. 
B) there is no nuclear membrane in eukaryotes. 
C) the bacterial DNA is in the nucleoid 
D) eukaryotic chromosomes are found in nucleoids. 
A) there is no nuclear membrane in prokaryotes. 
B) there is no nuclear membrane in eukaryotes. 
C) the bacterial DNA is in the nucleoid 
D) eukaryotic chromosomes are found in nucleoids.

Question 10

How was E.coli was used to aid in the cloning of the bioluminescent genes from Vibrio fischeri?

Accepted Answer

A) Gene fragments from V.fischeri were transformed into E.coli and bioluminescent E coli were selected 
B) Gene fragments from V.fischeri were cloned into plasmids transformed into E.coli and then reftransformed back into V.fischeri. 
C) Gen fragments from E.coli were used to disrupt the bioluminescent genes of V.fischeri by homologous recombination 
D) Transposons from E.coli were used to mutagenized the bioluminescent genes of V.fischeri. 
A) Gene fragments from V.fischeri were transformed into E.coli and bioluminescent E coli were selected 
B) Gene fragments from V.fischeri were cloned into plasmids transformed into E.coli and then reftransformed back into V.fischeri. 
C) Gen fragments from E.coli were used to disrupt the bioluminescent genes of V.fischeri by homologous recombination 
D) Transposons from E.coli were used to mutagenized the bioluminescent genes of V.fischeri.

Question 11

What would be the phenotype of a nonsense mutation in the lac repressor function?

Accepted Answer

A) constitutive expression of the Lac operon. 
B) inducible expression of the Lac operon. 
C) permanently repressed expression of the Lac operon. 
D) cannot predict what would happen to expression of the Pac operon 
A) constitutive expression of the Lac operon. 
B) inducible expression of the Lac operon. 
C) permanently repressed expression of the Lac operon. 
D) cannot predict what would happen to expression of the Pac operon

Question 12

What term describes a second level of regulation of the trp operon that occurs in TrpR- mutants suggesting that it is repressor independent?

Accepted Answer

A) modulation 
B) derepression 
C) attenuation 
D) amplification 
A) modulation 
B) derepression 
C) attenuation 
D) amplification

Question 13

In the trp operon, attenuation occurs through translation of two Trp codons in the leader sequence.What would happen if these two codons were mutated to stop codons?

Accepted Answer

A) Region 1 will bind to region 3 in the absence of Trp.. 
B) The antiterminator loop will form easily. 
C) Region 3 will bind to region 4 in the absence of Trp. 
D) Region 3 will bind to region 1 in the presence of Trp. 
A) Region 1 will bind to region 3 in the absence of Trp.. 
B) The antiterminator loop will form easily. 
C) Region 3 will bind to region 4 in the absence of Trp. 
D) Region 3 will bind to region 1 in the presence of Trp.

Question 14

Why is it advantageous for transcription factors to be multimeric and for their binding sites to be clustered?

Accepted Answer

A) The affinity of the DNA-protein interactions are increased 
B) The specificity of the DNA-protein interaction is increased. 
C) It enhances the interaction of the DNA-proteins complexes to bind to the RNA polymerase. 
D) It decreases the competition for binding between different tanrscription factors for the same regulatory region. 
A) The affinity of the DNA-protein interactions are increased 
B) The specificity of the DNA-protein interaction is increased. 
C) It enhances the interaction of the DNA-proteins complexes to bind to the RNA polymerase. 
D) It decreases the competition for binding between different tanrscription factors for the same regulatory region.

Why is the analysis of transcriptomes useful for genetics research?

Small RNAs can regulate gene expression by

Catabolic pathways that break down complex substances into more usable units are usually regulated by the

How does tryptophan, the end product of the trp operon, function in the regulation of the operon?

As a general principle of gene regulation through operons, regulatory genes encode

How is glucose involved in the catabolite repression of the lactose operon?

Alterations to DNA sites such as promoters and operators can act

Transcription and translation can be coupled in bacteria but not eukaryotes since

How was E.coli was used to aid in the cloning of the bioluminescent genes from Vibrio fischeri?

What would be the phenotype of a nonsense mutation in the lac repressor function?

What term describes a second level of regulation of the trp operon that occurs in TrpR^- mutants suggesting that it is repressor independent?

In the trp operon, attenuation occurs through translation of two Trp codons in the leader sequence.What would happen if these two codons were mutated to stop codons?

Why is it advantageous for transcription factors to be multimeric and for their binding sites to be clustered?

Genetics: The Study of Biological Information

Mendels Principles of Heredity

Extensions to Mendels Laws

The Chromosome Theory of Inheritance

Linkage, Recombination, and the Mapping of Genes on Chromosomes

DNA Structure, Replication, and Recombination

Anatomy and Function of a Gene: Dissection Through Mutation

Gene Expression: The Flow of Information From DNA to RNA to Protein

Digital Analysis of Genomes

Analyzing Genomic Information

The Eukaryotic Chromosome

Chromosomal Rearrangements and Changes in Chromosome Number

Bacterial Genetics

Organellar Inheritance

Gene Regulation in Eukaryotes

Manipulating the Genomes of Eukaryotes

The Genetic Analysis of Development

The Genetics of Cancer

Variation and Selection in Populations

Genetics of Complex Traits

Filters

Exam 15: Gene Regulation in Prokaryotes

Why is the analysis of transcriptomes useful for genetics research?

Small RNAs can regulate gene expression by

Catabolic pathways that break down complex substances into more usable units are usually regulated by the

How does tryptophan, the end product of the trp operon, function in the regulation of the operon?

As a general principle of gene regulation through operons, regulatory genes encode

How is glucose involved in the catabolite repression of the lactose operon?

Alterations to DNA sites such as promoters and operators can act

Transcription and translation can be coupled in bacteria but not eukaryotes since

How was E.coli was used to aid in the cloning of the bioluminescent genes from Vibrio fischeri?

What would be the phenotype of a nonsense mutation in the lac repressor function?

What term describes a second level of regulation of the trp operon that occurs in TrpR- mutants suggesting that it is repressor independent?

In the trp operon, attenuation occurs through translation of two Trp codons in the leader sequence.What would happen if these two codons were mutated to stop codons?

Why is it advantageous for transcription factors to be multimeric and for their binding sites to be clustered?

Genetics: The Study of Biological Information

Mendels Principles of Heredity

Extensions to Mendels Laws

The Chromosome Theory of Inheritance

Linkage, Recombination, and the Mapping of Genes on Chromosomes

DNA Structure, Replication, and Recombination

Anatomy and Function of a Gene: Dissection Through Mutation

Gene Expression: The Flow of Information From DNA to RNA to Protein

Digital Analysis of Genomes

Analyzing Genomic Information

The Eukaryotic Chromosome

Chromosomal Rearrangements and Changes in Chromosome Number

Bacterial Genetics

Organellar Inheritance

Gene Regulation in Eukaryotes

Manipulating the Genomes of Eukaryotes

The Genetic Analysis of Development

The Genetics of Cancer

Variation and Selection in Populations

Genetics of Complex Traits

Filters

What term describes a second level of regulation of the trp operon that occurs in TrpR^- mutants suggesting that it is repressor independent?