Chapter 11 Quiz Questions Flashcards
Why do bacterial cells need to coordinate their metabolic reactions?
Adapt to changing conditions
Save energy
Produce compounds when needed
All answers are correct
All answers are correct
If a bacterium is grown within a nutrient rich medium that contains all of the amino acids required for protein synthesis, what will happen?
the bacterium will synthesize its own amino acids and only use the amino acids within the medium when energy levels are low in the cell
the bacterium will use the amino acids from the medium preferentially and not synthesize the amino acids until those in the medium are gone
the bacterium will use the amino acids within the medium, while also building new amino acids at the same time
the bacterium will synthesize its own amino acids and only use the amino acids within the medium when energy levels are high in the cell
the bacterium will use the amino acids from the medium preferentially and not synthesize the amino acids until those in the medium are gone
When the growth rate is held constant for bacteria
cells will release toxins to kill other cells of the same species
cells will be richer in certain components, especially RNA
cells will have the same macromolecular composition
cells will remove DNA to conserve energy
cells will have the same macromolecular composition
What coordinates metabolism within bacterial cells?
lipid activity and amounts
nucleic acid activity and amounts
enzyme activity and amounts
nothing, all reactions occur at the same time at the same levels
enzyme activity and amounts
Feedback inhibition is a method
used to control enzyme amount by phosphorylation
used to control enzyme amount by changing the amount of ATP available
used to control enzyme activity with a sRNA binding to mRNA
used to control enzyme activity through an allosteric change
used to control enzyme activity through an allosteric change
Gene expression is primarily controlled at which level in prokaryotes?
proteolysis
transcription initiation
post-translational modification
translation initiation
post-transcriptional modification
transcription initiation
Which of the following is true of regulation of protein synthesis in bacteria?
attenuation is a process that regulates proteolysis
there is only one type of sigma factor present in most bacteria that helps in promoter recognition
sRNA can downregulate transcription initiation
mRNA is generally very stable and has a half life of days to weeks
enhancers are proteins that bind to repressor DNA sequences to control transcription
sRNA can downregulate transcription initiation
Which of the following is TRUE regarding operons?
Operons contain structural genes that encode products that act in the same metabolic process
An operator is a sequence of DNA that acts in controlling whether an operon is expressed or not
All of the answers are true
The Lac operon is expressed when lactose is present and glucose isn’t
Operons contain genes that are transcribed using a common/single promoter sequence
All of the answers are true
Groups of operons regulated together are
regulons
sub-operons
genes
not possible
regulons
The stringent response system is
a regulon activated in response to oxidative damage
a modulon activated in response to lack of glucose
a modulon activated in response to starvation
a regulon activated in response to heat
a modulon activated in response to starvation
