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Worksheetsmicro test 3
Total questions: 153
Worksheet time: 1hrs 17mins
The evolutionary relationships in this figure were determined by
using fossil records of bacteria.
sequencing and comparing ribosomal RNA.
comparing phenotypic differences between cells.
determining which bacteria are able to interbreed.
Using the figure shown, which genus is most closely related to Chlamydia?
Treponema
Verrucomicrobium
Clostridium
Pseudomonas
An environmental sample from the ocean contains phototrophic bacteria that produce oxygen. How
would you classify these bacteria?
Information about the cell wall would be required to determine whether these bacteria are
Gram positive or Gram negative.
These bacteria must be cyanobacteria based on their production of oxygen.
It is highly probable that these bacteria are Gram-negative bacteria based on their presence
in a marine environment.
These bacteria must be chlamydia found within unicellular organisms.
Which of the following statements would most likely indicate an isolate is a Gram-positive bacterium
and excludes other bacteria?
The isolate was found in a soil sample.
The isolate forms dormant endospores.
The isolate is an intracellular pathogen.
The isolate produces oxygen.
Which of the following is NOT an example of a positive role that bacteria play in an ecosystem?
fixation of carbon dioxide into biomass
oxygen production
breakdown of pollutants
pathogenic relationship with humans
A bacterial disease previously known to only infect dogs begins to cause respiratory infections in humans who are in close contact with infected dogs. Which of the following explanations most likely explains the emergence of this new human pathogen?
The genome of the bacterium changed through horizontal gene transfer within the microbiota of the dog.
There was a mutation in the human genome that allowed the bacterium to attack human cells more vigorously.
The bacterium became infected by a mutation-inducing virus transmitted through flea bites on the dog.
The bacterium forms dormant endospores that remain in the environment even after the infected dogs are removed.
A soil sample taken shortly after a large chemical spill has occurred reveals only a few living bacteria. Six months later, a second sample from the same site reveals only a single bacterial species, which is present in high numbers. What may have caused this change?
This bacterial species was most likely left at the site by the original sampling equipment.
Animals passing through the area most likely deposited fecal matter full of microbiota.
The bacterial species found in high numbers contains at least one gene that provides a
competitive advantage.
The single bacterial species must have been within the gut of a shelter species.
Which of the following characteristics is associated with bacteria in the phylum Firmicutes and most likely helps them survive dryness?
a thick waxy coat that excludes Gram stain
horizontal gene transfer between two cells
thick cell walls with multiple layers of peptidoglycan
an ability to ferment sugars to lactic acid
Which of the following most likely preceded the division shown?
Nutrients became depleted.
Environmental temperature decreased to 10oC.
Nutrient availability increased.
Environmental moisture increased.
How can some Firmicutes persist in the environment for centuries?
Their unique cell shapes reduce surface area to prevent desiccation.
They form dormant endospores that remain viable for long periods of time.
They are able to slow their metabolism in vegetative cells when nutrients are depleted.
They produce a thick waxy coating when the environment becomes dry.
The mycelia of Streptomyces and other actinomycetes are known to produce
lactic acid
endospores
antibiotics
statins
Which one of the following diseases is NOT caused by Actinobacteria?
tuberculosis
leprosy
diphtheria
botulism
Your friend, Miguel, discovers a new bacterium and uses this bacterium to develop a popular new cheese with a taste similar to Swiss cheese. He is not willing to share his secret to success, but you suspect the bacteria he is using is a(n)
Firmicutes
Actinobacteria
cyanobacteria
spirochete
Which of the following statements most accurately describes Actinobacteria?
Most have an acid-fast property associated with unusual cell wall lipids that also protect
them from host defenses and antibiotics.
All Actinobacteria are considered to be pathogens in humans or other animals.
Most Actinobacteria are nonpathogenic in humans, but cause serious diseases in other
animals.
Many Actinobacteria produce endospores that allow them to survive for thousands of
years.
Which of the following does NOT accurately describe Pseudomonas aeruginosa?
causes opportunist infections in human surgical wounds
may form biofilms on pulmonary lining of cystic fibrosis patients
commonly grows in soil as a decomposer
may infect fleas, which transmit P. aeruginosa to humans
How is it possible for humans to use some Proteobacteria, such as Geobacter species, to generate
electricity?
Geobacter species use lipopolysaccharide, or LPS, within their outer membrane to store
energy that can be harnessed.
Geobacter species transfer electrons to electrodes in fuel cells because they transfer
electrons to iron or magnesium.
Geobacter species are heavily flagellated and display swarming behavior that generates
electricity.
Geobacter species produce gases during fermentation of carbohydrates, and these gases
are used in fuel cells.
Which of the following species causes an illness that can be prevented by immunization?
Bordetella pertussis
Neisseria gonorrhoeae
Vibrio cholera
Helicobacter pylori
Which of the following pathogens would most likely thrive in a growth media with an extremely low pH?
Haemophilus influenzae
Neisseria gonorrhoeae
Moraxella catarrhalis
Helicobacter pylori
There are multiple causative agents of pneumonia. Which of the following pairs below include two
bacterial species known to cause pneumonia?
Haemophilus influenzae and Moraxella catarrhalis
Neisseria gonorrhoeae and Vibrio cholera
Vibrio parahaemolyticus and Bordetella pertussis
Helicobacter pylori and Francisella tularensis
Which of the following is a characteristic found in all Enterobacteria?
a cell wall that stains Gram positive
facultative anaerobic rods
motility provided by flagella
obligate aerobes
What internal structure is indicated by arrows on this figure?
cilia
flagella
mitochondria
nucleus
Spirochete cells are unique because they possess
periplasmic flagella.
multiple nuclei.
a thick outer sheath of lipopolysaccharides.
two distinctive life stages.
A 23-year-old man visited a community clinic after receiving notification from the health department that a previous sexual partner was diagnosed with a sexually transmitted disease. Although he does not recall having any ulcers, he currently has a macular rash on his trunk, arms, hands, and feet. He is tested for evidence of
Treponema pallidum pallidum.
Treponema pallidum pertenue.
Chlamydia trachomatis.
Neisseria gonorrhoeae.
Which of the following causative agents and diseases are correctly paired?
Borrelia burgdorferi; Lyme disease
Treponema pallidum; yaws
Treponema pallidum pertenue; relapsing fever
Borrelia recurrentis; syphilis
A long, tight, spiral-shaped bacteria is found in the gut of termites. This bacteria is most likely a(n)
enterobacteria and a pathogen.
chlamydia and an intracellular parasite
spirochete and a symbiont.
cyanobacteria and a pathogen.
How is the specialized shape of a spirochete advantageous?
The shape of a spirochete allows it to rotate and move in a corkscrew motion through
viscous environments.
The shape of a spirochete allows spirochetes to divide more rapidly than cells of other
shapes.
The shape of a spirochete prevents osmotic shock, which is experienced by cocci and rods
only.
The shape of a spirochete provides protection from phagocytosis and antibiotics
A black Labrador puppy goes swimming in a nutrient-rich pond one summer afternoon. Within hours the puppy begins vomiting and showing signs of damage to his nervous system. The puppy’s owner takes him to a local veterinarian and is told the puppy also has liver damage. Upon questioning, the owner recalls the pond water the puppy went swimming in was green and cloudy. The veterinarian suspects the puppy was exposed to
elementary bodies produced by a Chlamydia species.
toxins produced by a spirochete.
reticulate bodies produced by a Chlamydia species.
toxins produced by a cyanobacteria.
What is the relationship between plants and cyanobacteria?
Plants produce chlorophylls a and b and pass these pigments on to cyanobacteria.
Cyanobacteria use oxygen produced by plants and, in return, produce carbon dioxide for
use in plants.
Some cyanobacteria form mutualistic relationships with plants, called lichens.
Cyanobacteria that were internalized and not broken down by plant cells formed
chloroplasts.
Cyanobacteria and the bacterial genus Rhizobium are both known to contribute to the environment by
producing oxygen
fixing nitrogen.
decomposing dead matter
producing antibiotics.
A blue-green bloom of cyanobacteria leads to an ocean beach closure. What is the primary concern?
Cyanobacteria indicate the presence of fecal matter in the water, which could lead to
intestinal illnesses.
Cyanobacteria are frequently pathogenic and could infect swimming humans.
Liver-damaging toxins produced by cyanobacteria could affect humans who come in
contact with the water.
Cyanobacteria consume oxygen in the water, and fish begin accumulating toxins as
31.
oxygen levels drop.
The most abundant phototrophs in the ocean are single-celled and include the genera
Treponema and Chlamydia.
Synechococcus and Prochlorococcus.
Merismopedia and Nostoc.
Oscillatoria and Campylobacter.
Which of the following statements correctly describes a lichen?
a mutualistic relationship in which spirochetes provide a scaffold for fungal growth
a mutualistic relationship in which cyanobacteria provide nitrogen to fungi
a parasitic relationship in which proteobacteria ferment sugars produced by fungi
a commensal relationship between Firmicutes and fungi that provides no benefits for
either organism
During infertility testing, a young woman is found to have pelvic inflammatory disease, or PID, from persistent inflammation of her fallopian tubes. Although she has never been treated for any sexually transmitted disease, her physician suspects she has an untreated bacterial infection, which is relatively common in the United States. Which bacteria is most likely causing her infection?
Borrelia burgdorferi
Chlamydia trachomatis
Borrelia recurrentis
Haemophilus influenza
Which of the following statements accurately describes the transmission of one Chlamydia species in
human populations?
Reticulate bodies in secretions from one individual attach to membranes in his or her
sexual partner.
Reticulate bodies remain dormant in the environment for years and attach to host cells
when humans come in contact with them.
Elementary bodies undergo replication within the gut of fleas and infect human cells when
fleas bite humans.
Reticulate bodies replicate inside host cells and develop into elementary bodies that are
released when cells lyse.
Trachoma, an ancient eye disease, is caused by
Borrelia burgdorferi.
Yersinia pestis.
Moraxella catarrhalis.
Chlamydia trachomatis.
A tissue sample from a woman’s reproductive tract reveals human cells that contain growing and dividing reticulate bodies with netlike chromosomes. Which of the following bacterial species has most likely infected the human cells?
Treponema pallidum
Helicobacter pylori
Chlamydia trachomatis
Coxiella burnetii
This figure shows two distinctive life stages associated with a bacteria that
has absent or diminished cell walls.
forms filamentous strands in marine environments.
causes syphilis.
produces oxygen.
The structure highlighted with an arrow in step 6 of this figure is best described as a
nucleus
lysosome
vacuole
mitochondrion
Which of the following is considered metabolically INACTIVE?
an elementary body of Chlamydia trachomatis
a reticulate body of Chlamydophila pneumonia
a vegetative Bacillus anthracis cell
a biofilm containing Bacteroides
Mycobacterium tuberculosis is a member of the Actinobacterium, which causes disease in humans, though other members of this group are environmental microorganisms and some produce useful antibiotics. Which other Actinobacterium is a pathogen of humans?
Corynebacterium diphtheria
Propionibacterium freudenreichii
Streptomyces coelicolor
Actinomyces israelii
The cell shown is best described as a
gamete
prokaryote
diploid cell
haploid cell
Which of the following occurs during gamete formation but NOT during asexual reproduction?
replication of all chromosomes
paired chromosomes condensing into short rods
separation of pairs of homologs
formation of nuclear membranes around groups of chromosomes
When comparing sexual reproduction to asexual reproduction, which of the following is an advantage
of sexual reproduction?
Sexual reproduction generates fewer diverse cell surface proteins and is less likely to
activate an immune response.
Sexual reproduction requires fewer resources that may be useful when nutrients are
depleted.
Sexual reproduction produces haploid vegetative cells, which are smaller than diploid
vegetative cells.
Sexual reproduction increases genetic diversity, which may be useful in a changing environment
The group of organisms that includes ciliates, dinoflagellates, and apicomplexans is known as
fungi
amebas
trypanosomes
alveolates
A major group of microbial eukaryotes that contains chloroplasts related to those of plants and is found as a single cell or sheet is
fungi
algae
alveolates.
trypanosomes
The parasite that causes malaria has a complex life cycle involving both a definitive and an intermediate host. This parasitic protist also contains an elaborate cortex. This parasite is best categorized as a(n)
fungus
trypanosome
alveolate
alga
Which of the following would be considered invertebrate parasites?
helminths
amebas
metamonads
algae
Which of the following would be considered “true” microbes?
nematode
cestodes
trematodes
fungi
When comparing invertebrate parasites to “true” microbes, which of the following is found in
invertebrate parasites only?
fully differentiated organ systems
cells with mitochondria
macroscopic forms
cells with nuclei
The fungal structure shown is best described as a
hyphapseudopod
mycelium
mushroom
fruiting body
One drug target for antifungals is the membrane lipid
chitin
hyphae
triazole
ergosterol
How do filamentous fungi grow in length?
Their hyphae undergo mitosis without cell division.
Their hyphae undergo meiosis to produce new cells.
They produce asci by mitosis without cell division.
They produce asci by meiosis without cell division.
Fungal filaments associated with the root systems of trees that expand the trees’ access to water and nutrients are known a
mycorrhizae
molds
chitin
saprophytes
The ability of fungi to digest lignin is important in the
production of bread.
production of beer.
decomposition of wood.
decomposition of animal bodies.
Which of the following best describes how fungi obtain nutrition?
Fungi use chloroplasts for photosynthesis.
Fungi secrete digestive enzymes and absorb broken-down molecules.
Fungi use phagocytosis to transport large molecules across their cell membrane.
Fungi harness cyanobacteria to receive carbon and other nutrients.
Why is it frequently more difficult to treat fungal infections in humans than it is to treat bacterial
infections?
The cells found in fungi and humans are more similar than cells of bacteria and humans.
Humans have not developed medications capable of targeting fungi.
Fungi normally grow in and on humans, and treating fungal infections would cause death
of the human.
Fungi undergo evolution at a much faster rate than bacteria do.
Aspergillus and histoplasmosis infections are both caused by
opportunistic skin contact with fungi.
smoking tobacco contaminated with fungal spores.
swimming in contaminated water.
inhalation of fungal spores.
Fungi that form spore-dispersing asci are known as
basidiomycetes
zygomycetes
microsporidia
ascomycetes
Cyanobacteria engulfed by an ancient proto-alga lead to the development of ________ in both algae and plants.
mitochondria
a nucleus
ribosomes
chloroplasts
Explain the environmental significance of algae and their relatedness to plants. MSC: Understanding
On an evolutionary timeline, which of the following organisms appeared first?
cyanobacteria
proto-algae
algae
plants
On an evolutionary timeline, which of the following organisms appeared last?
cyanobacteria
proto-algae
algae
plants
Filamentous amebas
form inorganic shells made of calcium carbonate.
contain large, bulky pseudopods.
move using cytoplasmic streaming.
utilize chloroplasts for photosynthesis.
Amoeba proteus, a lobed ameba, most likely moves by using
flagella
cilia
cytoplasmic streaming
needlelike pseudopods
What is the function of the process shown in the life cycle of Entamoeba histolytica?
This process forms a cyst that leaves the host and remains viable in water supplies for weeks.
This process forms a trophozoite that leaves the host and remains viable in water supplies
for weeks.
This process allows an ingested amebic trophozoite to develop into a cyst that can feed on
red blood cells.
This process allows an ingested amebic cyst to develop into a trophozoite that can feed on
red blood cells.
Blood and fecal samples are collected from a man with dysentery to determine the causative agent and
appropriate treatment. Which of the following would most clearly indicate amebic infection?
immunological tests indicating the presence of Shigella
a Wheatley’s trichrome stain indicating a protozoa with ingested red blood cells
a Gram stain indicating the presence of Gram-negative bacteria
an endospore stain indicating the presence of endospores
A free-living soil ameba may contaminate contact lens solutions and cause amebic keratitis. What is the genus name of one common causative agent of amebic keratitis?
Acanthamoeba
Entamoeba
Babesia
Toxoplasma
Which of the following is unique to ciliates?
presence of cilia
ability to use endocytosis
microtubules within cytoplasm
maintenance of two types of nuclei
The image shown indicates two paramecia of opposite mating types during one stage of conjugation in which haploid micronuclei are exchanged. Which of the following statements accurately describes the two cells after this stage is complete?
Both cells are haploid.
Both cells are diploid.
One cell is haploid and the other is diploid.
Both cells become gametes.
Which of the following would be most likely to stop transmission of Plasmodium falciparum and P.
vivax to humans?
ensure access to clean drinking water
provide mosquito netting for beds
check for ticks after walking in wooded areas
eliminate bedbugs from sleeping quarters
What is the function of the apical complex on a merozoite form of Plasmodium falciparum?
The apical complex is used for aerobic cellular respiration.
The apical complex is used to allow a merozoite to enter a red blood cell.
The apical complex is used to allow asexual reproduction.
The apical complex is used to provide energy for flagella.
Trypanosoma brucei, the parasite that causes African sleeping sickness, is carried by
deer ticks.
Anopheles mosquitoes.
tsetse flies.
bedbugs.
In the illustrated life cycle of the trypanosome, which of the following forms is nondividing?
slender
stumpy
procyclic
epimastigote
In the illustrated life cycle of the trypanosome, which of the following forms proliferates within the definitive host?
slender
stumpy
procyclic
epimastigote
Giardia lamblia and Trichomonas vaginalis are both metamonads. One similarity between the two species is
the presence of cilia.
the presence of flagella.
the production of cysts.
their ability to cross the placenta.
Which of the following organisms lacks the ability to use aerobic cellular respiration?
Giardia lamblia
Caenorhabditis elegans
Toxoplasma gondii
Taenia solium
Why is perianal itching significant in the life cycle of pinworms?
When a host scratches the anus, pinworm larvae enter the bloodstream.
Eggs are trapped under fingernails and transferred to new hosts.
Scratching allows mature worms to break through the surface of the skin.
Transmission of pinworms ends when the host scratches the anus.
On a trip to a region of Asia where snails commonly ingest trematode eggs, Rebecca refuses to eat escargot, cooked snails, offered by her roommate. Instead, Rebecca goes fishing because she feels it would be safer to eat fresh fish. Unfortunately, she undercooks the fish and develops a trematode infection. What is the most likely explanation for her infection?
Free-swimming larvae released by snails in the water developed into a secondary form within the fish.
The flesh of the fish she ate contained trematode eggs that developed into larvae within her intestine.
Her fish dinner was most likely contaminated by fecal matter in the water because trematode transmission is through a fecal-oral route.
There were dormant trematodes encysted within the flesh of the fish she ate.
The organism shown in this figure is a(n)
nematode
cestode
trematode
arthropod
Which of the following is a characteristic shared by mites, ticks, and lice?
Mites, ticks, and lice are all insects
Mites, ticks, and lice are all vectors for serious disease agents.
Mites, ticks, and lice are all ectoparasites.
Mites, ticks, and lice all deposit eggs within the skin.
The organism shown is designed for living
within the small intestine.
on the outer surface of the body.
within red blood cells.
on the outer surface of the liver.
What is the most likely cause of Frank’s deterioration following the use of an antibiotic agent?
Frank was allergic to the antibiotic used.
The infection would have progressed at the same rate regardless of the use of this
antibiotic.
Killing of the fungal cells causing the infection induced a severe immune response.
Frank acquired a secondary bacterial infection.
One positive use of viruses is their function as
infectious particles.
pandemic initiators.
cloning vectors.
marine predators.
Which of the following facts supports the argument that viruses are living?
Viruses lack metabolism for energy and biosynthesis.
Viruses are capable of being crystallized.
Some living pathogenic bacteria contain degenerate genomes and rely significantly on a
host.
Viruses cannot replicate without a host.
Which of the following is NOT a possible effect of viral replication in the host cell?
death of the cell
differentiation of the cell
debilitation of the cell
alteration of the genome of the cell
________ is an example of a virus that causes major economic losses in the agriculture industry.
Tobacco mosaic virus
Measles virus
HIV
Influenza
West Nile virus is capable of infecting many different organisms (humans, birds, raccoons, and so on).
Based on this information, which of the following statements correctly describes West Nile virus?
West Nile virus has a narrow host range.
West Nile virus has a broad host range.
West Nile virus has a narrow tissue tropism.
West Nile virus is capable of fecal-oral transmission.
Which of the following could possibly be an ancestor of the large asymmetrical DNA Vaccinia virus?
a degenerate single-celled organism
a bacteriophage
influenza
a cow
Which of the following is NOT caused by an aberrant protein?
Creutzfeldt-Jakob disease
scrapie
hepatitis
kuru
Which of the following is NOT a level of viral evolution?
within an organelle
within a host community
within a viral species population
within an individual organism
Which of the following characteristics of the rabies virus is most important for its classification?
complex capsid morphology
single-stranded, negative sense RNA genome
presence of an envelope
narrow host range
Examine the figure shown. Which viral classification group would be most NEGATIVELY affected by antiviral reverse transcriptase inhibitors?
Group III
Group IV
Group V
Group VI
Examine the figure shown. Which viral classification group must package a viral RNA-dependent RNA polymerase?
Group V
Group IV
Group III
Group II
________ ensures the presence and expression of host surface proteins capable of being bound to by viruses.
Transduction
Natural selection
Lysogeny
Lysis
Why is gelatin needed to culture animal viruses in tissue culture?
Animal viruses use gelatin as an energy source.
Cells in tissue culture require gelatin to grow.
Gelatin slows the dispersal of viruses from infected cells, allowing for plaques to form.
Gelatin is used to stain viral plaques.
________ bacteriophage infection results in immediate death of the host cell.
Lysogenic
Lytic
Latent
Chronic
If 100% of the DNA contents of a transducing bacteriophage were DNA from the host chromosome,
what would happen when the bacteriophage infected a new bacterial cell?
More bacteriophage would be synthesized, resulting in death of the new bacterial cell.
No more bacteriophage would be synthesized, as there is no bacteriophage genome
available to direct synthesis.
The new bacterial cell would die.
The bacteriophage would be converted from a lysogenic phage to a lytic bacteriophage.
Examine the figure shown. What is indicated by the lines?
plaques
bacterial cells
latent virus
animal virus
How is HPV able to keep its genome so small?
overlapping reading frames
oncogenic transformation
antigenic shift
HPV does not have a small genome.
Replication of HPV is activated when
the DNA is uncoated.
infecting basal cells.
integrating into the host genome
keratinocytes differentiate.
What type of HPV causes cancer?
all types of HPV
no types of HPV
some types of latent HPV
all types of actively replicating HPV
Why must the genome of HPV enter the nucleus for replication?
HPV uses its own polymerase that cannot function in the cytoplasm.
The pH of the nucleus allows for replication of HPV RNA.
The DNA genome of HPV can only be replicated in the nucleus where host DNA
polymerase is found.
The genome of HPV is not replicated in the nucleus.
Where are HPV virions assembled?
in the nucleus
in the cytoplasm
in the ribosome
outside the cell
Why would a virus have evolved to cause cancer in a host ce
to kill the host cell
to produce more cells for the virus to infect
to allow for increased mutagenesis of the virus
Viruses are not capable of causing cancer in a host cell.
What type of HPV can be eliminated from the body by the host immune system?
oncogenic HPV
nononcogenic HPV
all HPV
no HPV
Segmented influenza RNA genomes are capable of
reverse transcription.
cell fusion.
reassortment.
proviral transposition
Which of the following statements regarding the influenza virus is FALSE?
The genome of influenza is very tiny to allow the generation of as many virions as
possible.
The influenza genome maximizes gene reassortment.
The genome of influenza is well designed for evasion of the immune system.
The influenza genome allows for large quantities of virions to be created for continued
infection.
Which of the following stages of the influenza infection cycle is inhibited by Tamiflu?
the coating of the capsid envelope
the assembly of the capsid
the cleaving of the host receptor and release of the virus by budding
the packaging of viral genome segments and exit from the nucleus
Why must influenza have highly efficient host-to-host transmission?
because of its rapid infection
because of its slow infection
because of genetic reassortment
because of latent infection
What happens to the host cell after budding of new influenza virions?
It becomes cancerous.
It becomes transformed.
Nothing happens.
It is destroyed.
Which of the following characteristics do HPV and HIV have in common?
They are both retroviruses.
They both have overlapping genes.
They are both DNA viruses.
The have the same tissue tropism.
What is the cure for infection with HIV?
vaccine
radiation
antiviral drugs
There is no cure for HIV.
Why are so few HIV virions released in the blood actually infectious?
Reverse transcriptase has a high error rate.
HIV is not a very infectious virus.
The immune system inhibits these virions from causing infections.
ery few cells in the immune system express the receptor HIV requires for binding.
A small subset of the human population does not express the CD4 and CCR5 receptors. To what virus are these individuals naturally immune?
HIV
HPV
Influenza
Hepatitis
Which of the following features of HIV is a big reason as to why thus far it cannot be cured?
It is a retrovirus.
It contains a viral envelope.
It contains integrase.
It contains a protease.
Which of the following viruses is capable of causing a syncytium?
Hepatitis
Influenza
HPV
HIV
Which of the following is true of papillomavirus infection?
Genital HPV can be contracted via contact with warts on another person’s skin, for
example a wart on the fingers.
Condoms provide full protection against genital HPV.
Freezing or otherwise removing genital warts eliminates the infection.
The HPV vaccine can prevent infection with cancer-causing HPV strains.
In which of the following mechanisms of microbial control might some pathogens still survive?
sanitization
antisepsis
disinfection
sterilization
Which of the following organisms is NOT killed by a germicidal agent?
bacteria
virus
fungi
endospore
Hannibal Lecter, an infamous serial killer, is attempting to use H2O2 to remove pesky blood stains of his latest victim from his 100% cashmere scarf and for disinfection purposes. Why is it taking him so long to disinfect his scarf?
H2O2 is not a good disinfection agent.
This type of disinfection procedure is best completed at colder temperatures.
Blood is an example of organic load that can inhibit the process of disinfection.
The organisms on his scarf are resistant to H2O2.
Which of the following terms can describe the death rate of microbial cells when exposed to an antibacterial agent?
linear
exponential
reverse logarithmic
polar
Standard conditions for sterilization by ________ are 121°C and 15 psi for 20 minutes.
autoclaving
pasteurization
tyndallization
lyophilization
12D is the amount of time required to
kill 10^12 spores.
kill 10^12 cells.
reduce the population by 10^12.
kill 90% of the population.
Glycerol is used to protect cells during
refrigeration
deep-freezing
lyophilization
filtration
Which of the following is NOT a purpose of low temperatures in microbiology?
inhibit microbial growth
stop microbial metabolism
kill microorganisms
preserve microorganisms
Because it is an essential component for every individual, if enough vitamin C is not found in the diet, supplements may be required. Vitamin C is sensitive to heat. So that it can be safe for human consumption, how can vitamin C be sterilized before being packaged into supplements?
autoclave
pasteurization
filtration
lyophilization
Which of the following does NOT affect the sensitivity of a microorganism to food irradiation?
genome size
rate of repair of DNA damage
whether the food is fresh or frozen
the presence of heat-shock enzymes
Which of the following is NOT a factor affecting the efficacy of a disinfectant?
the barometric pressure
the presence of blood
the presence of endospore-forming bacteria
the corrosiveness of the disinfectant
Examine the table shown. Which disinfectant is the most effective against Salmonella typhi based on the phenol coefficient?
chloramine
mercury chloride
formalin
hydrogen peroxide
________ with the structure R-CHO are very useful disinfectants.
Iodophors
Low-molecular-weight aldehydes
Anionic detergents
Cationic detergents
Which of the following disinfectants has a high CDC level of activity?
hydrogen peroxide
quarternary ammonium compounds
phenol
chlorine gas
Which of the following is NOT a characteristic of biofilms that makes it resistant to disinfectants?
presence of an extracellular matrix
stress-induced physiology of surface cells
stress-induced physiology of cells deep in the biofilm
metabolic collaboration between multiple species
Drug sensitivity occurs when a(n)
drug is broken down by a pathogenic organism.
organism is inhibited by a drug.
individual develops an allergic reaction to a drug he or she is taking.
drug that is used to inhibit the growth of an organism is no longer capable.
The term antibiotic is usually reserved for drugs that target
viruses
bacteria
fungi
protozoa
Which of the following statements regarding the minimum inhibitory concentration (MIC) is FALSE?
The MIC is the same for one drug regardless of bacterial species.
The MIC is the lowest concentration of a drug that will prevent the growth of an organism.
The MIC can be affected by how well a drug penetrates a cell.
The MIC can be affected by the affinity of the drug for the intracellular target.
Which of the following is NOT a standard parameter of the Kirby-Bauer test?
the size of the agar plate
the depth of the medium
moderate composition
the method of spreading organisms onto the plate
Drug A has a toxic dose of 17 g/kg of body weight and a therapeutic dose of 8 g/kg of body weight. Drug B has a toxic dose of 6 g/kg of body weight and a therapeutic dose of 4 g/kg of body weight. Which of the following statements is true?
Drug B is the safer drug.
Drug A is the safer drug.
Drug B has a higher therapeutic index.
Drug A has a lower therapeutic index.
The cotreatment of septic Enterococcus infections with vancomycin and an aminoglycoside is an example of antibiotic
synergism
antagonism
sensitivity
resistance
The function of polymyxin is similar to that of a detergent. What cell structure will be most affected by this drug?
cell membrane
cell wall
ribosome
chromosome
Which antibiotic inhibits the formation of the peptide side chain of NAM?
vancomycin
cycloserine
bacitracin
cephalexin
Which of the following will result from inhibited topoisomerases?
no cell wall synthesis
deficient plasma membrane
impaired DNA synthesis
impaired RNA synthesis
Which antibiotic resistance mechanism is exemplified by beta-lactamase?
destroy the antibiotic before it gets into the cell
modify the target so that it no longer binds the antibiotic
add modifying groups that inactivate the antibiotic
pump the antibiotic out of the cell
Administering antibiotics before knowing the cause of the infection is specifically known as
chemotherapy
empirical therapy
prophylactic therapy
persistence therapy
Which of the following actions of an individual will NOT inhibit the need for antibiotics?
frequent hand washing
aromatherapy
avoiding the use of antibiotics for viral infections
vaccinations
What would inhibition of viral envelope acidification do to an influenza infection?
It would inhibit it
It would enhance it
It would have no effect
It would speed it up
How do DNA analogs act to inhibit replication of an RNA virus?
DNA analogs do not inhibit RNA viruses
by inhibiting RNA polymerase
by inhibiting DNA polymerase
by preventing protein synthesis
Protease inhibitors are a common antiviral drug targeting
HPV
HIV
hepatitis C
influenza
Highly active antiretroviral therapy is used to treat
HPV
HIV
hepatitis C
influenza
Viruses cause more illnesses on an everyday basis than do bacteria. Why are there so few antiviral
agents compared to antibacterial agents?
Viruses are a bigger problem in developing countries where they do not have the funds to
develop antiviral drugs.
Since viruses are not living, there are no drugs that can stop their proliferation.
Viruses use functions of the host to replicate themselves, so achieving selective toxicity is
difficult.
Viruses do not cause as many deadly diseases and therefore have not been targeted with
antivirals.
Which of the following is NOT a category of antifungal agents?
polyenes
azoles
allylamines
cephalosporins
How is griseofulvin selectively toxic?
it inhibits DNA synthesis of fungal DNA only
it disrupts the mitotic spindle of fungi but not humans
it blocks synthesis of a fungal cell wall
it inhibits synthesis of fungal-specific ergosterol
Fungal cells grown in the presence of fluconazole have
impaired cell division
mutations in DNA
defective cells walls
effective cell membranes
What is the major downside to the often necessary long-term treatment with fungal drugs?
dry skin
high cost
anti fungal resistance
potential side effects
The first antibiotic used to treat Molly, ampicillin, has activity against both Gram-negative and Gram- positive bacteria; however, the bacterium that made Molly ill was resistant to this agent. At the time the antibiotic was prescribed, neither the type of agent nor its resistances were known. Based on this information, which of the following is true?
Ampicillin is a broad-spectrum antibiotic.
Gram-positive bacteria are resistant to ampicillin, so it should be used only for Gram-
impaired cell division.
Molly’s illness should have been treated with a narrow-spectrum antibiotic.
Molly’s infection is resistant to a broad variety of antibiotics.
