Archaea have a unique form of conjugation involving cytoplasmic bridges for
bidirectional transfer of DNA.
What is the main form of nitrogen found on Earth?
A) N2
B) NO
C) NO3–
D) NH4
You want to know whether the virulence genes present in Bordetella pertussis are
evolutionarily related to genes in the less pathogenic species B. bronchiseptica or if the
virulence genes were acquired via horizontal gene transfer. What characteristic(s)
would you compare to answer this question?
A) percentage of GC content and codon usage
B) genome size and number of introns
C) number of genes in the pan genome
D) ribosomal binding site and intron sequence
Using phase contrast microscopy on a wet mount of live cells, you observe motile
bacilli moving rapidly and randomly through the field of view, changing directions after
a brief tumble and taking off in a different direction. These cells are exhibiting
________ motility.
A) twitching
B) swimming
C) gliding
D) twitching or gliding
Cryptosporidium parvum oocysts are highly resistant to
A) heat.
B) filtration.
C) desiccation.
D) chlorine.
Based on the functional roles of phosphate in various microbial metabolisms, deduce
which compounds phosphate exists as in microorganisms.
A) organic compounds
B) inorganic compounds
C) both organic and inorganic compounds
D) neither organic nor inorganic compounds
By controlling the concentration of nutrients added into a chemostat continuously, cells
can constantly be maintained at
A) exponential growth phase.
B) stationary growth phase.
C) log or stationary growth phase.
D) death growth phase.
From the standpoint of the microorganism, in glycolysis the crucial product is
A) ATP; the fermentation products are waste products.
B) ethanol or lactate; ATP is a waste product.
C) CO2; ATP is a waste product.
D) not relevant because glycolysis is not a major pathway.
Recognizing pathogens that contain multiple unique proteins which enable the human
immune system to recognize just one and mount an effective response has opened the
door on development of some vaccines only being
A) attenuated carrier viruses.
B) monovalent.
C) subunit vaccines.
D) purified protein administered.
The mechanism by which antigen-reactive cells respond to foreign antigens while
ignoring self-antigens is called clonal
A) selection.
B) deletion.
C) anergy.
D) expansion.
TH cells express a ________ protein coreceptor.
A) CD4
B) CD8
C) CD12
D) T cell receptin
What was produced by photosynthesis before the cyanobacterial lineage developed on
Earth?
A) oxygen
B) elemental sulfur
C) ferrous iron
D) hydrogen sulfide
What unit is isotopic fractionation reported as?
A) parts per billion
B) parts per million
C) parts per thousand
D) parts per trillion
What is thought to be the maximum temperature for life to exist?
A) 125C
B) 150C
C) 250C
D) 500C
Plasmids that govern their own transfer are known as
A) transformable.
B) transmutable.
C) conjugative.
D) transfective.
Carboxydotrophic bacteria oxidize carbon monoxide to
A) carbon dioxide.
B) methane.
C) acetate.
D) glucose.
If you were exposed to a sick animal that was found to have negri bodies in its nervous
system in a postmortem examination, how would you be treated to prevent disease?
A) passive and active immunization against rabies
B) antibiotics to treat Lyme disease
C) antiviral medication
D) observation to detect tick or lice bites
. Travelers should be vaccinated against yellow fever when traveling to Sub-Saharan
Africa or South America.
Mercury is NOT used in
A) electronics.
B) neurotoxins.
C) pesticides.
D) paper pulping.
A surprising finding of environmental metagenomic studies is that a majority of genes
in the environment are
A) from microbes grown in the lab.
B) viral in origin.
C) eukaryotic in origin.
D) from extinct microorganisms.
The primary energy source for termites comes from
A) acetogenic Archaea.
B) acetogenic Bacteria.
C) methanogenic Archaea.
D) methanogenic Bacteria.
For what purpose would a microbial ecologist use a microsensor?
A) to determine the concentration of cells in small increments in a sediment or water
column
B) to determine the expression of a particular gene in a microbial community
C) to quantify the uptake of a radioactive material
D) to determine the concentration of O2, N2O, or other chemical species in small
increments in a sediment or water column
Within Archaea and Bacteria, one megabasepairs of DNA encode about ________ open
reading frames.
A) 10
B) 100
C) 1,000
D) 10,000
The ability to form endospores in bacteria within Bacillales, Clostridiales, and
Lactobacillales suggests the genotype/phenotype evolved
A) at least three separate times in these divergent orders.
B) at least once, and horizontal gene transfer among relatives explains its presence in
other orders.
C) only once in an ancestor to these three orders, due to the high number of genes
required.
D) either at least once and horizontal gene transfer among relatives occurred or once in
a common ancestor.
The metabolic process of ammonification ________ ammonia.
A) oxidizes
B) produces
C) reduces
D) transforms
Secondary disinfection of drinking water is necessary to
A) maintain sufficient residual in the water distribution system to inhibit microbial
growth.
B) prevent the formation of biofilms on pipes in the water distribution system.
C) neutralize taste- and odor-producing organic compounds.
D) kill Cryptosporidium and other resistant pathogens.
In photosynthesis, NADH and NADPH are produced from NAD+ and NADP+ by
A) oxidation reactions.
B) reduction reactions.
C) both oxidation and reduction reactions.
D) neither oxidation nor reduction reactions.
When is a bacterial cell more likely to be phagocytized?
A) when antibody binds antigen on its surface
B) when compliment binds an antigen-antibody complex
C) when antibody recognizes self antigens
D) after antibody class-switching
Two major environmental extremes of the deep sea are high ________ and low
________.
A) pressure / nutrient levels
B) nutrient levels / pressure
C) temperature / pressure
D) oxygen / pressure
The Golgi complex functions to
A) modify and secrete proteins to the external environment.
B) sort proteins used within the cell.
C) both modify and sort proteins into those destined for secretion and those that
function in membrane structures.
D) synthesize proteins.
For microbial biodiversity studies, it is common to identify the ________ rather than
the ________ as a measure of biodiversity.
A) organisms themselves / genes
B) genes / organisms themselves
C) cell types / genes
D) cell types / organisms themselves
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.
Describe the use of combination drugs and why they are effective. Provide examples.
Draw a rooted phylogenetic tree containing seven organisms labeled A to G. Label your
tree with the following terms: branches, extant taxa, nodes, last common ancestor, and
an outgroup.
Compare the operation and function of a trickling filter system and activated sludge.
How does Clostridium perfringens cause food poisoning? How is this process related to
the metabolism and special structures of C. perfringens?
Propose a series of procedures to determine whether a patient has a urinary tract
infection.
Describe the mechanisms by which certain prokaryotes glide. What are the ecological
advantages of gliding motility?
Explain the stages of syphilis. What are the characteristics of and treatments required at
each stage?