The most frequent way in which regulatory RNA molecules exert their effects is by
A) base pairing with other RNA molecules that have regions of complementary sequence.
B) binding to a repressor and repressing enzyme transcription.
C) acting as an inducer that then binds to an activator protein to allow transcription to proceed.
D) signal transduction.
When a Bacillus anthracis population suddenly must form spores to survive a harsh nutrient poor environment, how do the cells obtain energy?
A) Cells in a growth phase that have not used up all of their energy will be the only ones to make endospores, which is why relatively few endospores are often made from a large population.
B) Intracellular energy reserves are quickly made available to produce endospores.
C) Slow responding cells are cannibalized by others that already began spore formation.
D) Global regulation is initiated to minimize energy waste in biosynthetic pathways and catabolic pathways are increased to consume remaining usable substrates to fuel spore formation.
To be most sensitive to a repellant, a methyl-accepting chemotaxis protein must be ________ methylated to initiate a ________.
A) fully / run
B) fully / tumble
C) not / run
D) not / tumble
The function of a kinase is
A) methylation.
B) response regulation.
C) phosphorylation.
D) glycosylation.
The promoters of positively controlled operons require activator proteins, because
A) RNA polymerase easily recognizes the consensus sequence.
B) they are required to inactivate the repressor proteins.
C) the promoters have nucleotide sequences that bind RNA polymerase weakly, which are not close matches to the consensus sequence.
D) they are needed to bind to the allosteric site of RNA polymerase.
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