Question 1

The terminator versus anti-terminator function of the T box-based riboswitch used by Gram-positive bacteria to regulate amino acid-related genes is determined by

Accepted Answer

A)  the binding of the appropriate uncharged tRNA.
B)  the rate of leader peptide synthesis.
C)  the binding of the T box binding protein.
D)  the utilization of the appropriate sigma factor by RNA polymerase.E) B) and D)
F) A) and B)

Question 2

During regulation by attenuation in the trp operon,if the pause and terminator loops form in mRNA,transcription is uncoupled to translation and protein synthesis is not occurring.

Accepted Answer

A) True 
 B)False

Question 3

In general,riboswitches regulate in Gram-negative bacteria such as Escherichia and in Gram-positive bacteria such as Bacillus.

Accepted Answer

A)  transcription; translation
B)  translation; transcription
C)  replication; translation
D)  transcription; replicationE) B) and C)
F) C) and D)

Question 4

The THI-element is part of the operon that controls synthesis of thymine in mRNA.

Accepted Answer

A) True 
 B)False

Question 5

Which is a false statement regarding riboswitches?

Accepted Answer

A)  Riboswitches are regions in the 5' untranslated leader of an mRNA.
B)  The effector molecules that bind to riboswitches are proteins.
C)  When the effector binds the riboswitch,it may serve to terminate transcription of its target mRNA.
D)  When the effector binds the riboswitch,it may serve to continue transcription of its target mRNA.E) A) and C)
F) A) and B)

Question 6

If flagellar rotation of Escherichia coli cells is ,then CheA is .

Accepted Answer

A)  counterclockwise; unphosphorylated
B)  counterclockwise; autophosphorylated
C)  clockwise; autophosphorylated
D)  clockwise; unphosphorylatedE) C) and D)
F) A) and C)

Question 7

An sRNA is isolated from a bacterial cell.What would you do to determine whether it is a cis-encoded or a trans-encoded sequence?

Accepted Answer

A)  Identify whether or not the sRNA sequence is complementary to the coding strand of mRNA gene target.
B)  Analyze the molecular position of hydrogen atoms in the sRNA nucleotides.
C)  Determine whether the sRNA binds to mRNA or to tRNA.
D)  Find out if the sRNA acts as a transcriptional or as a translational inhibitor.E) A) and B)
F) None of the above

Question 8

When the Catabolite Activator Protein binds to its binding site in DNA,it

Accepted Answer

A)  displaces repressors.
B)  bends the DNA.
C)  promotes the assembly of other transcription factors at the promoter.
D)  eliminates the need for a sigma factor on the part of RNA polymerase.E) A) and D)
F) B) and C)

Question 9

When tryptophan levels in a cell are low,a cell will stall transcription but continue translation of the tryptophan operon.

Accepted Answer

A) True 
 B)False

Question 10

__________ alter repressor proteins thereby increasing the rate of transcription initiation.

Accepted Answer

A)  Inducers
B)  Corepressors
C)  Effectors
D)  ModulatorsE) A) and D)
F) A) and B)

Question 11

Which of the following statements best explains why microbial geneticists initially focused on regulation of gene expression at the transcriptional,rather than the translational,level?

Accepted Answer

A)  By regulating the first step of protein synthesis,cells conserve the greatest amount of energy.
B)  The process of transcription was best understood by researchers at the time.
C)  Cellular regulation of transcription is common to all prokaryotic cells.
D)  The process of synthesizing an mRNA transcript is much less complex than translation of mRNA into protein.E) A) and B)
F) A) and D)

Question 12

During sporulation in Bacillus subtilis,inactive precursor forms of new sigma factors are activated at the appropriate time by which mechanism?

Accepted Answer

A)  Proteolysis
B)  Phosphorylation
C)  RNA-binding
D)  Chaperone refoldingE) None of the above
F) A) and B)

Question 13

Serratia marcescens bacteria has a gene that regulates red pigment production by cells.A student inoculates two nutrient agar plates of Serratia and incubates one at 25oC and the other at 37oC.Following incubation,the student observes that colonies on the 25oC plate are red while those on the 37oC plate are nonpigmented.Which of the following statements is a logical conclusion based on these results?

Accepted Answer

A)  Serratia genes for pigment production are induced at certain temperatures.
B)  This is an example of constitutive gene expression.
C)  Low temperatures cause repression of certain housekeeping genes.
D)  Serratia cells undergo a genotypic change that is proportional to changes in temperature.E) All of the above
F) B) and C)

Question 14

During tryptophan synthesis in Escherichia coli,the 1:2 attenuator sequence of mRNA is called the pause loop.

Accepted Answer

A) True 
 B)False

Question 15

In the presence of both glucose and lactose,the lactose repressor is not bound to the operator and the genes of the lactose operon are expressed.

Accepted Answer

A) True 
 B)False

Question 16

If Escherichia coli is cultured in broth containing both glucose and lactose,it

Accepted Answer

A)  uses glucose preferentially until the supply is exhausted,then uses lactose.
B)  uses lactose preferentially until the supply is exhausted,then uses glucose.
C)  uses glucose and lactose simultaneously.
D)  uses only the glucose (it cannot use lactose as a source of carbon) .E) C) and D)
F) B) and C)

Question 17

The sensing of starvation that leads to sporulation in Bacillus subtilis is accomplished by a .

Accepted Answer

A)  small RNA
B)  sensor kinase
C)  response regulator
D)  quorum regulatory effectorE) A) and C)
F) A) and B)

Question 18

______________ is used to control transcription of some anabolic pathways involved in amino acid biosynthesis.

Accepted Answer

A)  Attenuation
B)  Catabolite repression
C)  Induction
D)  All of the choices are correct.E) A) and C)
F) B) and C)

Question 19

The inducer for the
E.coli lac operon is allolactose produced by the action of permease on lactose.

Accepted Answer

A) True 
 B)False

Question 20

In terms of transcription regulation,the role of a helix-turn-helix is most similar to that of a(n)  .

Accepted Answer

A)  zinc finger
B)  sigma factor
C)  poly-A tail
D)  guanine capE) All of the above
F) A) and B)

Exam 14: Regulation of Bacterial Cellular Processes

If flagellar rotation of Escherichia coli cells is ,then CheA is .

Correct Answer
verified

During sporulation in Bacillus subtilis,inactive precursor forms of new sigma factors are activated at the appropriate time by which mechanism?

Correct Answer
verified

An sRNA is isolated from a bacterial cell.What would you do to determine whether it is a cis-encoded or a trans-encoded sequence?

Correct Answer
verified

When the Catabolite Activator Protein binds to its binding site in DNA,it

Correct Answer
verified

In general,riboswitches regulate in Gram-negative bacteria such as Escherichia and in Gram-positive bacteria such as Bacillus.

Correct Answer
verified

The inducer for the E.coli lac operon is allolactose produced by the action of permease on lactose.

Correct Answer
verified

When tryptophan levels in a cell are low,a cell will stall transcription but continue translation of the tryptophan operon.

Correct Answer
verified

During regulation by attenuation in the trp operon,if the pause and terminator loops form in mRNA,transcription is uncoupled to translation and protein synthesis is not occurring.

Correct Answer
verified

During tryptophan synthesis in Escherichia coli,the 1:2 attenuator sequence of mRNA is called the pause loop.

Correct Answer
verified

In terms of transcription regulation,the role of a helix-turn-helix is most similar to that of a(n) .

Correct Answer
verified

__________ alter repressor proteins thereby increasing the rate of transcription initiation.

Correct Answer
verified

______________ is used to control transcription of some anabolic pathways involved in amino acid biosynthesis.

Correct Answer
verified

The THI-element is part of the operon that controls synthesis of thymine in mRNA.

Correct Answer
verified

Which of the following statements best explains why microbial geneticists initially focused on regulation of gene expression at the transcriptional,rather than the translational,level?

Correct Answer
verified

Which is a false statement regarding riboswitches?

Correct Answer
verified

In the presence of both glucose and lactose,the lactose repressor is not bound to the operator and the genes of the lactose operon are expressed.

Correct Answer
verified

Correct Answer
verified

The sensing of starvation that leads to sporulation in Bacillus subtilis is accomplished by a .

Correct Answer
verified

If Escherichia coli is cultured in broth containing both glucose and lactose,it

Correct Answer
verified

The terminator versus anti-terminator function of the T box-based riboswitch used by Gram-positive bacteria to regulate amino acid-related genes is determined by

Correct Answer
verified

Exam 14: Regulation of Bacterial Cellular Processes

If flagellar rotation of Escherichia coli cells is ,then CheA is .

Correct AnswerverifiedShow Answer

During sporulation in Bacillus subtilis,inactive precursor forms of new sigma factors are activated at the appropriate time by which mechanism?

Correct AnswerverifiedShow Answer

An sRNA is isolated from a bacterial cell.What would you do to determine whether it is a cis-encoded or a trans-encoded sequence?

Correct AnswerverifiedShow Answer

When the Catabolite Activator Protein binds to its binding site in DNA,it

Correct AnswerverifiedShow Answer

In general,riboswitches regulate in Gram-negative bacteria such as Escherichia and in Gram-positive bacteria such as Bacillus.

Correct AnswerverifiedShow Answer

The inducer for the E.coli lac operon is allolactose produced by the action of permease on lactose.

Correct AnswerverifiedShow Answer

When tryptophan levels in a cell are low,a cell will stall transcription but continue translation of the tryptophan operon.

Correct AnswerverifiedShow Answer

During regulation by attenuation in the trp operon,if the pause and terminator loops form in mRNA,transcription is uncoupled to translation and protein synthesis is not occurring.

Correct AnswerverifiedShow Answer

During tryptophan synthesis in Escherichia coli,the 1:2 attenuator sequence of mRNA is called the pause loop.

Correct AnswerverifiedShow Answer

In terms of transcription regulation,the role of a helix-turn-helix is most similar to that of a(n) .

Correct AnswerverifiedShow Answer

__________ alter repressor proteins thereby increasing the rate of transcription initiation.

Correct AnswerverifiedShow Answer

______________ is used to control transcription of some anabolic pathways involved in amino acid biosynthesis.

Correct AnswerverifiedShow Answer

The THI-element is part of the operon that controls synthesis of thymine in mRNA.

Correct AnswerverifiedShow Answer

Which of the following statements best explains why microbial geneticists initially focused on regulation of gene expression at the transcriptional,rather than the translational,level?

Correct AnswerverifiedShow Answer

Which is a false statement regarding riboswitches?

Correct AnswerverifiedShow Answer

In the presence of both glucose and lactose,the lactose repressor is not bound to the operator and the genes of the lactose operon are expressed.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

The sensing of starvation that leads to sporulation in Bacillus subtilis is accomplished by a .

Correct AnswerverifiedShow Answer

If Escherichia coli is cultured in broth containing both glucose and lactose,it

Correct AnswerverifiedShow Answer

The terminator versus anti-terminator function of the T box-based riboswitch used by Gram-positive bacteria to regulate amino acid-related genes is determined by

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified