The arrangement of Class II MHC proteins in pairs or trimers enhances their stability.
Several fluorogenic dyes can be used simultaneously in a sample as long as they each
emit light at a different measurable wavelength.
The proton motive force is most often generated by splitting of H2.
A patient with AIDS often dies of a variety of infections caused by opportunistic
microorganisms.
Some sulfur-oxidizing bacteria can simultaneously reduce nitrate, which enables them
to grow anaerobically.
Photosystem I is responsible for splitting a water molecule in the first step of oxygenic
electron flow.
Insertion sequences are found on both ends of transposons and encode for transposase.
Heme prosthetic groups are involved in electron transfer with quinones.
In a chemostat, growth rate and growth yield can be controlled independently.
Food and water are considered disease vehicles.
Green fluorescent protein (GFP) is used for detecting translational activity of a fused
protein, whereas lacZ reporters are used to detect transcriptional activity of a fused
gene.
Although the domain Archaea contains many acidophilic organisms, there are still
many others within the domain that grow well in environments with a neutral pH.
Protists are NOT normally found in the gastrointestinal tract of healthy individuals.
Pseudomonads are aerobic, gram-positive, polar flagellated, bacillus-shaped cells.
R plasmids help prevent the spread of virulence factors.
Unicellular cyanobacteria are the most abundant phototrophs in the ocean and perform
80% of marine photosynthesis.
The physiochemical conditions of a microenvironment, by definition, remain static.
Unlike the 16S rRNA gene phylogenetics used to identify relatedness in Bacteria, the
18S rRNA gene is by itself unreliable for phylogeny of members in Eukarya.
The pink-red rash of scarlet fever may be caused by streptococcal pyrogenic exotoxins
A, B, C, and E, which are coded for on a lysogenic bacteriophage.
The biodegradation pathway for benzoate is likely to be subject to induction rather than
repression.
The discipline of microbiology is intimately associated with biochemistry and genetics,
because cells are both biochemical catalysts and genetic coding devices.
The cytoplasmic membrane of Picrophilus is extremely acid impermeable at very low
pH.
Certain species of Bacteria have been identified to cause obesity.
Engineering a metabolic pathway enables a researcher to use different genes from
unrelated organisms.
Virtually ALL cases of tetanus occur in individuals who have failed to receive tetanus
toxoid booster immunizations.
Identifying bactoprenol inside the rare bacteria that lack peptidoglycan would be
unexpected considering its role in membrane biosynthesis.
Many gammaproteobacteria members are obligate intracellular symbionts of
eukaryotes, which also enables many to become human pathogens.
A temperate virus does not exist as a virus particle inside the host cell.
Due to such an array of nutrients, microorganisms are often capable of sustaining
exponential growth in the environment.
Combined with autofluoresence or fluorescent DNA probes, flow cytometry can
separate or count populations of cells from aquatic environments.
Heat shock proteins are produced at high numbers to minimize damaging effects during
high heat conditions as well as other stress signals unrelated to heat such as ultraviolet
radiation.
Chlorinated xenobiotics can ONLY be degraded aerobically, thus making them very
recalcitrant if they accumulate in anoxic environments.
If vaccinia viruses were not both immunogenic and relatively benign, they would likely
not be a favored vehicle for vaccinations.
Sudden nutrient perturbations in an environment generally ________ the overall
prokaryotic diversity.
A) increase
B) decrease
C) maintain
D) replicate
F– strains of Escherichia coli
A) do not have an F factor.
B) have the F factor as a plasmid.
C) have an integrated F factor.
D) transfer the F factor to other strains at a high frequency.
The person who described the “wee animalcules” was
A) Robert Hooke.
B) Antoni van Leeuwenhoek.
C) Louis Pasteur.
D) Ferdinand Cohn.
Which of the following is a major growth-limiting micronutrient that influences
microbial growth?
A) iron
B) transferrin
C) lactoferrin
D) sugar
The propagation cycle that occurs in acid mine drainage is caused by
A) reduction of Fe3+ by sulfuric acid.
B) the oxidation of sulfide to sulfuric acid by microbial oxidation of iron (Fe3+).
C) microbial sulfate reduction.
D) low pH and high oxygen concentrations.
Which genus produces hyaluronidase?
A) Mycobacteria
B) Streptococcus
C) Shigella
D) Procholorococcus
Which of the following proteins is NOT required for homologous recombination?
A) Hfr
B) RecA
C) proteins having helicase activity
D) endonuclease
In Bacteria, the MOST common oxidized form of nitrogen is ________ and of sulfur is
________.
A) nitrate / sulfate
B) nitrate / sulfite
C) nitrite / sulfate
D) nitrite / sulfite
Psychrotolerant microorganisms can survive and grow at
A) refrigeration temperatures.
B) boiling temperatures.
C) extreme fluctuations in water availability.
D) high salt or sugar concentrations.
The T4 phage protects its DNA from host restriction endonucleases by
A) glucosylating cytosine bases in the T4 genome to prevent DNA cleavage.
B) methylating all four bases (A, T, C, G) in the T4 genome to prevent DNA cleavage.
C) integrating the viral genome into the host genome where it will not be degraded.
D) circularizing the viral genome so that it will not be degraded.
The bioenergetics of anaerobic respiring Archaea such as those of the Crenarchaeota
involve ________ from which ________ is synthesized.
A) proton translocation / ATP
B) substrate level phosphorylation / ATP
C) sodium translocation / ATP
D) substrate level phosphorylation / GTP
What is the biological function of endospores?
A) They are bacterial reproductive structures.
B) They enable organisms to endure extremes of temperature, drying, and nutrient
depletion.
C) They transport toxins.
D) Endospores can serve as reproductive structures, enable survival in harsh
environments, and transport toxins.
Lysogeny probably carries a strong selective advantage for the host cell because it
A) prevents cell lysis.
B) confers resistance to infection by viruses of the same type.
C) confers resistance to infection by viruses of a different type (or strain).
D) confers resistance to infection by many virus types and prevent cell lysis.
The mutualism of Azolla-Anabaena is useful for
A) aquaculturalists.
B) corn farmers.
C) rice farmers.
D) tropical forest community succession.
Which of the following is NOT a major question in the Human Microbiome Project?
A) Are differences in the relative abundance of different bacteria important?
B) Do differences in the human microbiome correlate with differences in human health?
C) Is there a correlation between microbial population structure and host genotype?
D) How can we reduce the number of microbes on the human body?
The disk-diffusion test is used for
A) assessing antimicrobial activity.
B) the identification of Escherichia coli.
C) the identification of viral plaques.
D) the detection of antigen.
Which statement BEST describes sewage and wastewater?
A) Wastewater is a subset of sewage.
B) Sewage is a subset of wastewater.
C) Wastewater and sewage are virtually synonymous.
D) Wastewater and sewage are both subsets of all liquid effluents from domestic and
industrial sources.
IgG, IgM, and IgA are examples of ________ found in blood.
A) antibodies
B) antigens
C) bacteria
D) pathogens
How is a bacteroid distinguished from a bacterial cell?
A) 16S rRNA gene sequencing
B) biochemical tests
C) cell morphology
D) 16S rRNA gene sequencing, biochemical tests, and cell morphology
What metabolic advantage do cells have in storing the elemental sulfur byproduct from
sulfide oxidation?
A) The cells avoid producing transport energy waste to secrete the sulfur.
B) The byproduct serves as an electron reserve for subsequent oxidation.
C) Sulfur decreases the intracellular acidification for non-acid-tolerant sulfide
oxidizers.
D) The byproduct can be used for other biosynthetic pathways that use sulfur, such as
Rieske Fe-S proteins.
How do bacteriophage influence bacterial evolution?
A) Bacteriophage cause cleavage and rearrangement of bacterial genomes, thus
accelerating bacterial evolution.
B) Bacteriophage lyse mutated bacterial cells, thus preventing them from replicating
and passing on their genetic information.
C) Bacteriophage transfer genetic information between bacterial cells through
transduction, thus increasing the genetic diversity of bacterial populations.
D) Bacteriophage decrease the size of bacterial populations and thus decreasing genetic
diversity and slowing down bacterial evolution.
Which of the following is NOT correct regarding DNA and RNA synthesis?
A) The overall direction of chain growth is from the 5′ to 3′ end.
B) Both processes require an RNA primer to begin.
C) The template strand is antiparallel to the newly synthesized strand.
D) DNA is the template for both DNA and RNA synthesis.
ALL fungal infections can broadly be termed
A) benign.
B) systemic.
C) superficial.
D) mycoses.
When culturing a chemoorganoheterophic bacterium, what outcome is LEAST likely to
occur if ammonia and phosphate are provided at equal concentrations?
A) Cells require much less P to grow than N, so extra P will be used for ATP synthesis
and result in a faster growth rate.
B) Cells will never consume all of the phosphate, because N is needed in higher
quantities than P.
C) The final biomass of cells will be no different than if only 50% of the phosphate was
provided.
D) The bacteria will import all of the ammonia to use for biosynthetic pathways.
Protein catalysts involved in the acceleration of the rate of chemical reactions are called
A) catalytic converters.
B) growth agents.
C) evolutionary molecules.
D) enzymes.
A geologist going through a sediment core is likely to find remnants of ancient calcium
carbonate containing ________ and silica containing ________.
A) diatoms / cercozoans
B) cercozoans / diatoms
C) chlorarachniophytes / foraminiferans
D) foraminiferans / chlorarachniophytes
How could you identify potential riboswitches with bioinformatics tools?
A) Advanced 3D modeling techniques of mRNA folding would be necessary because
complementary nucleotide binding predictions would not be useful.
B) Locate short regions of an individual transcript with several complementary sites.
C) Identify homologous sRNAs in other organisms.
D) Identify several complementary mRNAs encoded in the genome.
Ionizing radiation does NOT include
A) gamma rays.
B) UV rays.
C) X-rays.
D) cosmic rays.
Enhanced phagocytosis of antibody-sensitized cells is known as
A) complementation.
B) immunization.
C) opsonization.
D) tolerance.
Signal transduction pathways initiate activation of transcription after specific
A) TH cell death.
B) ligand-receptor binding on the cell surface.
C) cytokines diffuse across the cytoplasmic membrane.
D) antigen-antibody binding.
Water distribution systems contain
A) very few bacteria or other microorganisms.
B) biofilms that may harbor opportunistic pathogens.
C) numerous grazing protists that consume bacteria.
D) biofilms that may harbor opportunistic pathogens and numerous grazing protists that
consume bacteria.
Most drug-resistant bacteria isolated from patients contain a(n)
A) R plasmid.
B) T1 phage.
C) reverse transcriptase.
D) β-lactam.
Which feature, if changed, would NOT abolish M13’s utility as a cloning vector?
A) ssDNA genome becoming a dsDNA genome
B) loss of genes that make coat proteins
C) replacing the segment of non-coding DNA in its genome with an indispensible gene
D) switch from lysogenic to lytic lifestyle
What is the difference between pathogenic and non-pathogenic E. coli in relation to the
human host?
Explain the difference between the division rate and the generation time.
Compare and contrast the ectomycorrhizae and the endomycorrhizae.
Discuss why energy yield in an organism undergoing anaerobic respiration is less than
that of an organism undergoing aerobic respiration.
What are the similarities and differences between the Fe cycle and Ca cycle?
How would Si depletion in the photic zone of the open ocean affect the biological pump
and the C cycle?
Are superantigen reactions beneficial or harmful to the host? What is different about a
superantigen reaction compared to normal antigen-host cell interactions?
Explain the concept of coevolution in terms of host-pathogen interactions.
Why does an organism that is able to respire both aerobically and anaerobically
preferentially undergo aerobic respiration?
Influenza is an acute human viral disease that causes brief cellular damage followed by
healing and complete clearing of the virus from the body. Hepatitis C is a chronic viral
disease that causes slow destruction of tissue and persistent virions that are not
completely cleared. Which of these diseases is more likely to be caused by lytic virus
and which is caused by a lysogenic virus?
Compare and contrast the spread plate method and the pour plate method of doing plate
counts. Also describe which group of organisms would not be quantifiable in the pour
plate method but would still be observed in the spread plate method.
What is the function of an endospore and how is an endospore formed?
Why are most sexually transmitted diseases (STDs) transmitted only by intimate
person-to-person contact?
Why does Archaeoglobus represent a metabolically transitional type of organism that
bridges the energy-generating processes of H2S production and methanogenesis?
What is the difference between a primary and secondary insect symbiont? Propose how
you might use an insect symbiont to control the spread of an insect-borne disease.
Consider mumps. What is the causative agent? How is this disease spread? What
happens in the body during the course of this disease? What type of immunity is
conferred or used for this disease? Why is the prevalence of mumps in developed
countries generally low?