Bacteria that are capable of oxidizing both iron and sulfur usually have a strong
preference for sulfur oxidation because it yields more energy.
Rhodobacter and Roseobacter are two genera with a common ancestor in
Alphaproteobacteria.
Th17 cells are important in the first stages of the adaptive immune response.
Inorganic pollutants such as metals and radionuclides can be completely destroyed
through bioremediation.
Nearly ALL cases of acute listeriosis require hospitalization.
Failure to reach equilibrium with a disease agent could result in extinction for a host
species.
Inflammation is the usual outcome of an adaptive immune response but not an innate
immune response.
Bacteria that produce acetate use the same metabolic pathways regardless of whether
they are growing in the presence or absence of oxygen.
The bubonic plague was caused by Yersinia pestis, a highly pathogenic virus.
Foraminifera that form test structures are exclusively found in marine waters.
Salt in mannitol salt agar inhibits the growth of Staphylococcus aureus.
Salmonella is commonly associated with wound infections.
According to our present understanding, each of the three major domains has what is
known as its own universal ancestor.
Many halophiles require a high ionic environment for survival.
Vaginal acidity in the adult female is due to acid production by Lactobacillus
acidophilus.
The loss of CD4 T-helper cells leads to the overt consequences of an HIV infection.
Viruses that contain positive-strand genomes are incompatible to share genetic elements
other positive-strand genomes.
The MOST metabolically diverse phylum of Bacteria known to date is the
Proteobacteria.
Erythrocytes are the most numerous cells in human blood.
Molecular evidence suggests that leeches contain two distinct bacterial communities in
their bladder.
Oxygen was a driving factor in the formation of eukaryotic cells.
Plant diversity is generally lower in environments where mycorrhizae are associated
with plants due to strong coevolution, which leads to competitive exclusion.
In the absence of susceptible hosts, Clostridium tetani would still survive in nature.
Class I MHC proteins have grooves with open ends.
A negative-stranded RNA virus produces a complete positive-stranded RNA virus that
serves as template DNA for other proteins in order to replicate the complete
negative-stranded RNA genome.
The majority of cases of human plague in the United States occur in the northeastern
states.
There are currently no known predatory bacteria that are adapted to invade or kill
nearby cells.
In the natural carbon cycle, carbon dioxide is returned to the atmosphere by the
respiration of animals and chemoorganotrophic microorganisms.
Teichoic acids are commonly found in gram-negative cell walls.
PRRs were FIRST observed in phagocytes in Drosophila (where they are called Toll
receptors).
Genes found on plasmids DO NOT impact metabolism or cellular structures.
Strong promoters used for genetic manipulation are usually regulated by specific
molecules.
The embedded peptides in MHC proteins are normally derived from breakdown
products of cell metabolism.
Many microbial habitats are unsuitable for plants and animals.
Emerging infectious disease will likely affect only developing countries in the near
future.
Despite the invariance of the peptidoglycan backbone’s structure, there are more than
100 different types of peptidoglycan.
Mercury can serve as a transcriptional activator in the regulation of certain genes.
Bacteria that contain complex internal membrane systems are more likely to divide by
budding than by binary fission.
There are two different mating types in the yeast Saccharomyces cerevisiae, and they
can switch from one type to another.
With modern molecular techniques, it is now possible to completely assemble a genome
from a single cell.
Which of the following cytokines acts to stimulate natural killer cells and induce nave T
cells to differentiate to TH1 cells?
A) IL-1β
B) IL-6
C) IL-12
D) TNF-α
A pseudomonad that loses its R plasmid in the soil is LEAST likely to
A) cause an infection in a human.
B) colonize a surface.
C) infect a shrub.
D) survive a habitat dominated by antibiotic-producing Streptomyces spp.
LUCA is
A) the last universal common ancestor.
B) the individual ancestor of each of the three domains.
C) actually somewhat of a misnomer because it is now believed that each of the
domains arose independently.
D) All of the answers are correct.
The study of the occurrence, distribution, and determinants of health and disease in a
population is the field of
A) microbiology.
B) immunology.
C) epidemiology.
D) virology.
A key concept in evolution is that all mutations are
A) random.
B) neutral.
C) deleterious.
D) either deleterious or beneficial.
Antigen-presenting cells present antigens to
A) B lymphocytes.
B) T lymphocytes.
C) dendritic cells.
D) neutrophils.
The biggest limitation of traditional light microscopy and electron microscopy methods
is that they are unable to reveal
A) absolute cell concentration.
B) cellular components of small microbes because of the limits of magnification.
C) genetic and functional diversity of microorganisms in the habitat under study.
D) physical microbial interactions as found in nature.
Obligate symbiotic fungi that form associations with plants by entering the cortical cells
of plants without invading the plant cell’s membrane are called ________ and include
the genus ________.
A) ectomycorrhizae / Agaricus
B) ectomycorrhizae / Glomus
C) endomycorrhizae / Agaricus
D) endomycorrhizae / Glomus
The rate of contaminant microbial growth during the exponential phase in food depends
on
A) temperature.
B) the nutrient value of the food.
C) water content.
D) temperature, nutrient value, and water content.
________ is a strict anaerobe with an optimum growth temperature of 105C that grows
chemolithotrophically on H2 with S0 as an electron receptor or chemoorganotrophically
on complex mixtures of organic compounds.
A) Pyrodictium
B) Pyrolobus
C) Pyrobaculum
D) Desulfurococcus
Multilocus sequence typing involves sequencing several different
A) genomes.
B) housekeeping genes.
C) tRNA genes.
D) rRNA genes.
What would the result be when a soil is supplemented with S0?
A) dimethyl sulfide production due to mixotrophs
B) organic carbon production due to anaerobes
C) soil acidification due to chemolithotrophs
D) syntrophic utilization of sulfite
Which of the following hemolysins is a phospholipase?
A) lecithinase
B) Streptolysin-O
C) Staphylococcal -toxin
D) leukocidin
Which statement is TRUE regarding the ecological role of plant degradation by fungi?
A) In brown rot the cellulose is attacked preferentially, and the lignin is left
unmetabolized.
B) In brown rot the lignin is attacked preferentially, and the cellulose is left
unmetabolized.
C) In white rot the cellulose is attacked preferentially, and the lignin is left
unmetabolized.
D) In white rot the lignin is attacked preferentially, and the cellulose is left
unmetabolized.
Bdellovibrio species are ________ cells that replicate in the ________.
A) symbiotic / gills of clams
B) lithotrophic / deep subsurface
C) predatory / periplasmic space
D) denitrifying / sediments of freshwater lakes
Frozen methane molecules are called
A) anhydrous methane.
B) anoxic methane.
C) methane anhydrates.
D) methane hydrates.
________ are intracellular bacteria that are usually localized to specialized organs
within their host.
A) Symbiodinium
B) Arbuscules
C) Epibionts
D) Endosymbionts
Bioluminescence is catalyzed by luciferase, which creates light by
A) shunting electrons from FMNH2 to O2, which releases energy in the form of light.
B) reversing photosynthesis.
C) hydrolyzing ATP.
D) reducing LuxR.
Based on oxygen requirements and metabolic strategies, isolating an
epsilonproteobacterium from ________ would likely be MOST fruitful.
A) anoxic and sulfate-rich waters
B) a plant’s rhizosphere
C) sulfate-rich anoxic-oxic interfaces
D) sulfide-rich soils
A mutant of Rhizobium leguminosarum is able to survive and reproduce in the
laboratory outside of plant roots, but can no longer initiate root nodule formation. What
type of genes are most likely mutated in this mutant?
A) rhz genes
B) myc genes
C) nif genes
D) nod genes
Widespread antimicrobial drug resistance is usually passed by
A) heterologous gene expression.
B) reverse transcription.
C) horizontal gene transfer.
D) gene splicing.
Which group of bacteria is most famous for their diversity of antibiotics produced?
Hypothesize an ecological role production of these antibiotics might have in such
environments where they are not produced at high enough levels to kill bacteria.
Bacteria stain as gram-positive or gram-negative because of differences in the cell
A) wall.
B) cytoplasm.
C) nucleus.
D) chromosome.
Which phenotypic assay could be used to determine whether a new Streptococcus sp. is
of the pyogenes or viridans group?
A) catalase assay with H2O2
B) hemolytic type after growth on a blood agar plate
C) occurrence of cells being in clusters or as individual cells under a microscope
D) product(s) formed during lactose fermentation
Bioremediation ________ by introducing pollutant-consuming microorganisms or
specific nutrients that help microorganisms degrade pollutants.
A) accelerates the natural cleanup process
B) exploits genetic exchange mechanisms
C) invokes microbial evolution
D) uses chemotaxis of biodegrading microorganisms
Oomycetes (“water molds”) contain ________ in their cell walls, while most fungi have
________ in their cell walls.
A) cellulose / chitin
B) chitin / cellulose
C) silica / chitin
D) cellulose / silica
The measurable strength of binding of antibody to antigen is called
A) binding affinity.
B) epitope.
C) tolerance.
D) virulence.
The process by which electrons from the quinone pool are forced against the
thermodynamic gradient to reduce NAD+ to NADH is called reverse
A) proton motive force.
B) reduction.
C) electron transport.
D) energy flow.
Which of the following is a novel antimicrobial target?
A) disruption of lipid biosynthesis
B) inhibition of protein synthesis
C) inhibition of cell wall biosynthesis
D) inhibition of peptidoglycan crosslinking
In gram-positive Bacteria, the cell walls are composed mainly of thick ________
layers.
A) protein
B) poly-β-hydroxybutryic acid (PHB)
C) lipopolysaccharides (LPS)
D) peptidoglycan
Describe the mutualistic relationship between chemolithotrophic bacteria and tube
worms in hydrothermal vents.
Compare and contrast dengue fever and West Nile fever. Which disease would be easier
to eradicate and why?
Considering the evolution of Bacteria, the criteria used for taxonomy, and the genetic
requirements for individual metabolic pathways, explain how it is unlikely to observe
three genera of the same family where one genus has strict anaerobes that degrade only
small aromatics, another genus degrades large molecular weight sugars aerobically, and
a third is a photoautotroph.
How can epidemiologist differentiate between common-source and host-to-host
epidemics based only on the incidence of disease?
After transcription, mRNA may undergo significant editing. Compare and contrast RNA
editing in prokaryotes and eukaryotes and connect how these differences affect genome
size and gene content.
Why must the adaptive immune system develop a capacity to discriminate between
foreign antigens and host antigens?
Where does the rabies virus reproduce? Using a specific example, explain the
implication this has with the virus’s incubation time and infection site.
Using a specific example, explain the term “accidental host.”
Describe how FISH can be used to determine which cells within a microbial community
are actively degrading toluene. Assume the genes involved in the metabolic pathway
have been sequenced from several microorganisms and vary only slightly from one
another.
What type of microscope would you use to visualize the internal structures of a
chloroplast? Support your conclusion with evidence based on the size of the structures
you want to see and the resolution and magnification power of different types of
microscopes.
Summarize the evolution of sequencing technology beginning with the Sanger method.
What is the basic flow of genetic information in all cellular life? Include in your answer
a diagram that illustrates the relationships between the basic components and steps in
the flow of genetic information.
Design an experiment (including controls) to determine if a new kitchen chemical
cleaner is mutagenic. Include in your answer how you would interpret the results.
Rhodobacter cells perform photosynthesis in the presence of light and grow
heterotrophically in the dark. After being cultured in total darkness for multiple
generations phenotypic and genotypic changes occur. What phenotypic changes occur
and what evolutionary processes are driving them?
Describe the general processes that occur in a sludge digester. What is an advantage of
sludge digestion over activated sludge?
During stationary phase, group members of Serratia produce prodigiosins that contain
pyrrole. Considering its structural relatedness to other pyrrole-containing molecules of
known function (e.g., chlorophylls, bacteriochlorophylls, porphyrins), propose a
potential ecological role for these compounds in soil where they are involved in
something other than photosynthesis.