Chapter 14 Flashcards
(44 cards)
When arabinose is present in the environment, the AraC protein acts as a(n) ______________ for the E. coli ara operon.
activator
When there is no arabinose available in the environment, the AraC protein acts as a(n) ______________ for the E. coli ara operon.
repressor
If a set of genes is repressed in the presence of the controlling substance, it is referred to as __________ control.
negative
If a set of genes is induced in the presence of the controlling substance, it is referred to as __________ control.
positive
(T/F) The binding of arabinose to the AraC protein allows it to form a loop in the DNA upstream of the ara operon promoter.
False
(T/F) Two-component signal transduction systems are found in the Bacteria, but not in Archaea.
False
(T/F) The real inducer for the E. coli lac operon is allolactose produced by the action of permease on lactose.
False
(T/F) 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.
False
(T/F) Small RNAs that regulate translation by binding to the leader region of mRNAs are called antisense RNAs.
True
____________ is used to measure the amount of a chemoattractant encountered over time.
Methylation
(T/F) One way to regulate gene expression is through the production of different sigma factors. These cause RNA polymerase to bind to different sets of promoters, thereby altering the pattern of gene expression.
True
(T/F) Gene regulation during sporulation in Bacillus subtilis involves BOTH temporal and spatial control.
True
In order for high level expression of the E. coli lac operon to occur, a complex of catabolite activator protein and __________ must be bound to the DNA near the promoter.
cAMP
A collection of genes or operons controlled by a common regulatory protein is called a(n) ___________.
regulon
Regulation of gene expression serves to do all of the following except….
a.conserve energy and raw materials.
b.maintain balance between the amounts of various cell proteins.
C.adjust the activity of existing proteins in the cell.
d.adapt to long-term environmental change.
In two component regulatory systems, the response regulator typically receives a ____________ from the sensor kinase when it has been activated….
a.pyruvate group
B.phosphoryl group
c.acetyl group
d.methyl group
While standard two-component regulatory systems typically act to control gene transcription, phosphorelay systems can act either to control gene transcription or to control…..
a.translation.
B.protein activity.
c.DNA replication.
d.all of the choices.
The sensor kinase for the OmpF: OmpC two-component regulatory system is….
a.the OmpK protein.
B.the EnvZ protein.
c.the MicF RNA.
d.none of the choices.
The E. coli lac operon has ________ operator sequences….
a.one
b.two
C.three
d.four
So-called two-component regulatory systems…
a.include a sensor kinase and a response regulator.
b.play a key role in regulating sporulation in Bacillus.
c.play a key role in regulating the OmpF and OmpC porin proteins in E. coli.
D.all of the choices
If Escherichia coli is cultured in broth containing both glucose and lactose, it…
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).
__________ activate repressor proteins thereby decreasing the synthesis of certain enzymes….
a.Inducers
B.Corepressors
c.Effectors
d.Modulators
__________ alter repressor proteins thereby increasing the rate of transcription initiation…..
A.Inducers
b. Corepressors
c. Effectors
d. Modulators
______________ is used to control transcription of some anabolic pathways involved in amino acid biosynthesis….
A.Attenuation
b. Catabolite repression
c.Induction
d. All of the choices
