ST 6 questions Flashcards
Of the redox couples below, which would NOT represent a molecule that could be reduced in anaerobic respiration and, in its reduced form, one that could be oxidized by a lithotroph?
NO3- / NO2-
Fe3+ / Fe2+
SO42- / H2S
NO3- / N2
NO3- / N2
egarding bacterial and archaeal electron transport chains, which is FALSE?
Question options:
They are not always located in the plasma membrane
They all contain quinones
They all generate proton motive force
The microbes direct the flow of electrons based on their immediate metabolic requirements
They are not always located in the plasma membrane
Among the molecules below, which would be a substrate for assimilatory reduction, but NOT dissimilatory reduction?
Question options:
NO3-
N2
CO2
SO42-
N2
For an organism that can use NO3- as a terminal electron acceptor, which would definitely be TRUE?
Question options:
The organism would not produce superoxide dismutase
The organism is a lithotroph
The organism could grow at the bottom of a stab tube or Winogradsky column
Incubation in a glove jar or anaerobic jar would be required
The organism is an obligate anaerobe
The organism could grow at the bottom of a stab tube or Winogradsky column
Regarding the membrane-bound ATP synthase, which is FALSE?
Question options:
In some microbes, it can catalyze oxidative phosphorylation
In some microbes, it can catalyze photophosphorylation
In some microbes, it can catalyze substrate-level phosphorylation
In microbes that lack an electron transport chain, it is used to generate proton motive force
In some microbes, it can catalyze substrate-level phosphorylation
Not including the rhodopsin-based phototrophs, which is NOT true of the bacterial phototrophs?
Question options:
Some, but not all, are photosynthetic
The different taxa can be distinguished by the absorption spectra of their pigments
Upon absorption of a photon of light, the reaction centre pigment undergoes photoionization
They all produce reducing power using noncyclic electron flow
They all make ATP by cyclic and noncyclic photophosphorylation
Upon absorption of a photon of light, the reaction centre pigment undergoes photoionization
Which is TRUE?
Question options:
Bacteriorhodopsin is a light driven proton pump in some photosynthetic bacteria
When a reaction centre chlorophyll or bacteriochlorophyll absorbs a photon of light, it becomes a strong reducing agent
The green sulfur bacteria contain chlorophyll and are aerobic
The photosynthetic antenna system transfers electrons to the ETS
When a reaction centre chlorophyll or bacteriochlorophyll absorbs a photon of light, it becomes a strong reducing agent
omparing a purple sulfur bacterium and a cyanobacterium, which is TRUE?
Question options:
They both use reverse electron transport to generate reducing power
They both contain carotenoid accessory pigments
They are both aerobic
They both contain chlorophyll as their primary photosynthetic pigment
They both contain carotenoid accessory pigments
Regarding lithotrophy, which is FALSE?
Question options:
For some, biomass is made from organic carbon sources
Reduced minerals may serve as electron donors for an electron transport chain
For the aerobic oxidation of ammonium, the ΔEo’ would be positive
It is a form of respiration
For some, biomass is made from organic carbon sources
Regarding metagenomics, which is FALSE?
Question options:
The microbial diversity of an environment is best determined by comparative sequence analysis of the PCR-amplified small subunit (SSU) rRNA genes
The number of distinct proteorhodopsin-containing taxonomic groups in a marine sample is best determined by comparative sequence analysis of the PCR-amplified proteorhodopsin genes
Detection of biosynthetic genes for bacteriochlorophyll in metagenomic DNA sequences would indicate the presence of anoxygenic bacterial phototrophs in the sample
Linking taxonomic group with their metabolic functions in a given environment is best determined by shotgun sequencing of metagenomic DNA
Linking taxonomic group with their metabolic functions in a given environment is best determined by shotgun sequencing of metagenomic DNA
Which is NOT a characteristic of Pelagibacter ubique?
Question options:
Makes reducing power through reverse electron transport
Makes ATP by oxidative phosphorylation
Makes ATP by photophosphorylation
Makes precursor metabolites through the central pathways
Makes ATP by substrate-level phosphorylation
Makes reducing power through reverse electron transport
Which is NOT characteristic of Acidithiobacillus ferrooxidans?
Question options:
Reducing power from reverse electron transport
Oxidizes its energy source on the outer face of the plasma membrane
Branched electron transport chain
Performs aerobic respiration
Produces and hydrolyzes ATP using the membrane-bound ATP synthase
Oxidizes its energy source on the outer face of the plasma membrane
