1. Which
of the following characteristics does NOT distinguish the archaea from the
bacteria?
A)
the types of transfer RNA used
B)
the rRNA sequences present
C)
the deoxyribonucleotides
D)
cell wall composition
E)
cell membrane composition
Answer : C. the deoxiribonucleotides
2. The
archaea known as halophiles
A)
require temperatures above 45C to survive.
B)
require salt concentrations of 9% or greater to survive.
C)
are members of the phylum Euryarchaeota.
D)
are members of the Euryarchaeota and require temperatures above 45C.
E)
are members of the Euryarchaeota and require salt concentrations above 9%.
Answer : E. are members of the euryarchaeota and require salt conentrations above 9%
3. The
largest known group of archaea is the
A)
thermophiles.
B)
halophiles.
C)
cyanobacteria.
D)
methanogens.
E)
hyperthermophiles.
Answer : D. methanogens
4. Which
of the following types of microbes might be found in the Dead Sea?
A)
hyperthermophiles
B)
phototrophic bacteria
C)
methanogens
D)
actinomycetes
E)
halophiles
Answer : E. Halophiles
5. Which
of the following groups of bacteria lives in environments similar to those that
may have existed on the early Earth?
A)
deeply branching bacteria
B)
cyanobacteria
C)
mycoplasmas
D)
thermophiles
E)
proteobacteria
Answer :A. deeply branching bacteria
6. Which of the following statements regarding cyanobacteria is FALSE?
A)
They are oxygenic.
B)
Many perform nitrogen fixation.
C)
They contain chlorophyll a.
D)
They may have given rise to mitochondria.
E)
Some are motile.
Answer : .
Answer : .
7. Heterocysts
are associated with
A)
mycoplasmas.
B)
alphaproteobacteria.
C)
cyanobacteria.
D)
myxobacteria.
E)
chlamydias.
Answer : C. Cyanobacteria
Answer : C. Cyanobacteria
8. Low
G + C Gram-positive bacteria are
A) Mycoplasma.
B)
in the phylum Firmicutes.
C) Clostridia.
D)
in the phylum Actinobacteria.
E)
in the phylum Firmicutes and include Clostridia and Mycoplasma
Answer : .
Answer : .
9. Which
of the following diseases is NOT associated with clostridia?
A)
tetanus
B)
diarrhea
C)
gangrene
D)
botulism
E)
diphtheria
Answer : E. Diphtheria
10. Mycoplasmas are pleomorphic because they
A)
have no cell walls.
B)
are low G + C Gram-positive bacteria.
C)
exhibit snapping division.
D)
have sterols in their cytoplasmic membranes.
E)
produce endospores
E) both Bacillus and Clostridium
Answer : A. have no cell walls
11. Which of the following bacterial genera produce(s) endospores?
A) Bacillus
B) Clostridium
C) Lactobacillus
D)
both Bacillus and Lactobacillus
E)
both Bacillus and Clostridium
12. Which of the following bacterial genera includes species that protect areas of the body such as the intestinal tract and the vagina from invasion by pathogens?
A) Staphylococcus
B) Listeria
C) Lactobacillus
D) Mycobacterium
E) Corynebacterium
Answer : C Lactobacillus
13. Which
of the following groups of bacteria is named for its resemblance to fungi?
A) Corynebacterium
B) Actinomyces
C) Clostridium
D) Lactobacillus
E) Staphylococcus
Answer : B) Actinomyces
14. Which
of the following bacterial genera is used for the degradation of environmental
pollutants?
A) Actinomyces
B) Streptomyces
C) Corynebacterium
D) Rhizobium
E) Nocardia
Answer : E) Nocardia
15. Which
of the following is NOT associated with bacteria in the genusStreptomyces?
A)
the "musty" smell of soil
B)
nutrient recycling in soil
C)
antibiotic production
D)
microbial antagonism
E)
protection of plants against caterpillars
Answer : E. protection of plats agaist catepillars
Answer : E. protection of plats agaist catepillars
16. Which of the following characteristics is the basis for distinguishing classes of proteobacteria?
A)
outer membrane carbohydrates
B)
cell wall structure
C)
G + C ratio
D)
ribosomal RNA sequences
E)
cytoplasmic membrane lipid composition
D. ribosomal RNA sequences
A)
alphaproteobacteria.
B)
betaproteobacteria.
C)
gammaproteobacteria.
D)
deltaproteobacteria.
E)
epsilonproteobacteria.
Answer : C. gammaproteobacteria
18. Members
of which of the following genera are the most common sexually transmitted
bacteria in the United States?
A) Bacteroides
B) Rickettsia
C) Chlamydia
D) Helicobacter
E) Treponema
Answer : C. Chlamydia
Answer : C. Chlamydia
D.
Borrelia
Which
of the following genera does NOT include intracellular parasites of other
cells?
A) Bdellovibrio
B) Chlamydia
C) Rickettsia
D) Borrelia
E) Legionella
A.
Alpha
Unusual
cellular extensions called prosthecae are associated with which of the
following groups of proteobacteria?
A)
alpha
B)
beta
C)
gamma
D)
delta
E)
epsilon
E) Nitrobacter, Rhizobium,
andAzospirillum
Which
of the following bacterial genera plays an important role in environmental
nitrogen cycles?
A) Nitrobacter
B) Rhizobium
C) Azospirillum
D)
both Nitrobacter and Rhizobium
E) Nitrobacter, Rhizobium,
and Azospirillum
C.
hyperthermophiles
)
Microbes growing in boiling hot mineral springs are generally
A)
methanogens.
B)
halophiles.
C)
hyperthermophiles.
D)
purple sulfur bacteria.
E)
cyanobacteria.
D.
both DNA and protein sequences
Classification
of bacteria into different phyla is based on comparisons involving which of the
following?
A)
DNA sequences
B)
cell wall composition
C)
protein sequences
D)
both DNA and protein sequences
E)
DNA and protein sequences, as well as cell wall composition
A.
Green phototrophic bacteria
Bacteria
that require hydrogen sulfide are generally members of the
A)
green phototrophic bacteria.
B)
cyanobacteria.
C)
halophiles.
D)
methanogens.
E)
thermophiles
B.
they are symbotic withplants and nitrogen fixation
Which
of the following statements regarding pseudomonads is FALSE?
A)
They are Gram-negative rods.
B)
They are symbiotic with plants for nitrogen fixation.
C)
They often contaminate food products.
D)
They include Pseudomonas and Azotobacter.
E)
They cause urinary tract infections.
D.
zoogloea
Which
of the following bacterial genera is useful for sewage treatment?
A) Burkholderia
B) Thiobacillus
C) Neisseria
D) Zoogloea
E) Nitrosomonas
A.
spirochete
A
flexible, spiral-shaped bacterium is called a
A)
spirochete.
B)
vibrio.
C)
coccobacillus.
D)
spirillum.
E)
sarcina.
E.
viviparity
The
"giant" bacterium Epulopiscium reproduces by means
of
A)
binary fission.
B)
snapping division.
C)
budding.
D)
sexual reproduction.
E)
viviparity.
B.
they gram stain positive
Which
of the following statements regarding mycoplasmas is FALSE?
A)
They are low G + C bacteria.
B)
They stain Gram-positive.
C)
They are pleomorphic.
D)
They exhibit a "fried egg" appearance on solid media.
E)
They are the smallest free-living cells.
A.
endospore production
The
anaerobic Clostridium species are troublesome pathogens
largely because of their capacity for
A)
endospore production.
B)
rapid reproduction.
C)
oxygen production.
D)
biofilm production.
E)
high salt tolerance.
E.
thermophiles
Prokaryotes
of the genus Pyrodictium are
A)
endospore formers.
B)
intracellular parasites.
C)
members of the deeply branching bacteria.
D)
halophiles.
E)
thermophiles.
C.
deeply branching bacteria
)
The __________ include the genus Aquifex.
A)
archaea
B)
proteobacteria
C)
deeply branching bacteria
D)
high G + C Gram-positive bacteria
E)
clostridia
E) an endospore
former responsible for food poisoning from rice.
The
bacterium Bacillus cereus is
A)
an endospore former.
B)
a frequent contaminant of milk and meat.
C)
responsible for food poisoning from rice.
D)
the cause of gastric ulcers.
E)
an endospore former responsible for food poisoning from rice.
B.
contaminated milk and meat
Listeria is
responsible for
A)
gastric ulcers.
B)
contaminated milk and meat.
C)
urinary tract infections.
D)
tuberculosis.
E)
"flesh-eating" bacterial infections.
D.
"flesh-eating" bacterial infections
One
species of the genus Streptococcus is the leading cause of
A)
tuberculosis.
B)
urinary tract infections.
C)
contaminated milk and meat.
D)
"flesh-eating" bacterial infections.
E)
food poisoning from rice.
A.
turberculosis
The
genus Mycobacterium includes species responsible for
A)
tuberculosis.
B)
urinary tract infections.
C)
food poisoning from contaminated dairy products.
D)
gastric ulcers.
E)
food poisoning from rice.
C.
gastric ulcers
The
genus Helicobacter is responsible for
A)
food poisoning from contaminated meat.
B)
food poisoning from rice.
C)
gastric ulcers.
D)
tuberculosis.
E)
urinary tract infections
B.
intracellulaar parasites
Members
of the genus Chlamydia are
A)
thermophiles.
B)
intracellular parasites.
C)
classified with the deeply branching bacteria.
D)
endospore-formers.
E)
Gram-positive bacteria.
E.
urinary tract infections
Pseudomonas species are occasional causes of
A)
food poisoning from contaminated meat.
B)
food poisoning from rice.
C)
food poisoning from dairy products.
D)
"flesh-eating" bacterial infection.
E)
urinary tract infections.
False
The
majority of archaea are extremophiles
True
or false
False
True or false
When
an endospore germinates, it gives rise to two daughter cells called vegetative
cells
True
True or false
Members
of the Streptomyces are environmentally important because they
can degrade a wide range of compounds including lignin from trees, chitin and
keratin from animals, and latex.
False
True or false
Halophiles
grow equally well in the presence or absence of high salt concentrations.
False
True or false
Cyanobacteria
contain chlorophyll a and carry out anoxygenic photosynthesis.
true
true or false
Cocci
can be spherical as well as kidney-shaped.
true
Some
strains of Staphylococcus aureus can invade the body and cause
diseases such as pneumonia and bacteremia.
True
or false
false
Mycoplasmas
are named for the large quantities of mycolic acid in their cell walls.
true
or false
true
Most
of the methane produced by methanogens is oxidized by other types of bacteria
before it affects the Earth's climate.
True
or false
True
Myxobacteria
exhibit traits, such as cooperation and differentiation, that are not normally
observed in prokaryotes.
True
or false
vegetative
A
bacterial cell that produces an endospore is called a(n) ___________ cell.
halophiles
Bacteria
that can colonize and spoil meats preserved with high concentrations of salt
are called __________.
cyanobacteria
Bacteria
that use chlorophyll a and engage in oxygenic photosynthesis,
just like plants and algae, are called __________.
akinetes
Thick-walled
spores produced by some species of cyanobacteria are called ___________.
tetrads
Regular
clusters of cocci that resemble a square are called __________.
genetic
The
G+C ratio is a ______ determination used in classifying the different taxa of
Gram-positive bacteria.
actinomycetes
The
___________ are a group of Gram-positive bacteria that form branching filaments
resembling those of fungi.
Streptococcus
The
genus of pathogenic cocci responsible for a wide range of human disease and whose
members grow in chains is ___________. (Be sure your answer is italicized.)
prosthecae
Unusual
structures associated with the alphaproteobacteria that consist of an extension
of the cytoplasm surrounded by the cytoplasmic membrane and cell wall are called
__________.
fixation
The
reduction of nitrogen gas to ammonia is called nitrogen __________.
Mycobacterium
Slow-growing
bacteria in the genus ___________ are able to withstand long exposure to air
because of the presence of mycolic acid in their cell wall structure. (Be sure
your answer is italicized.)
galls
Plant
tumors caused by Agrobacterium infections are called
___________.
bacteroids
The
___________ are a group of Gram-negative bacteria that include obligate
anaerobes normally found in the intestinal tracts of animals and humans.
elementary
The
infective stage of chlamydia is called the __________ body.
B.
number of microbial cells
1)
In microbiology, the term growth usually refers to an increase
in
A)
a microbe's size.
B)
the number of microbial cells.
C)
the amount of ATP produced.
D)
the number and size of microbial cells.
E)
the number and size of microbial cells and the amount of ATP produced.
A.
photoheterotroph
A
cell that uses an organic carbon source and obtains energy from light would be
called a
A)
photoheterotroph.
B)
lithoautotroph.
C)
photoautotroph.
D)
chemoheterotroph.
E)
chemoautotroph.
d.
obligated aerobic
A(n)
__________ organism is one that requires oxygen for growth.
A)
anaerobic
B)
facultative anaerobic
C)
aerotolerant
D)
obligate aerobic
E)
both aerotolerant and anaerobic
A.
phototroph
An
aquatic microbe that can grow only at the surface of the water is probably
which of the following?
A)
a phototroph
B)
a heterotroph
C)
a chemotroph
D)
a lithotroph
E)
an anaerobe
C.
peroxide anion
Which
of the following forms of oxygen is detoxified by the enzyme catalase?
A)
singlet oxygen
B)
hydroxyl radical
C)
peroxide anion
D)
superoxide radical
E)
molecular oxygen
D.
protease
All
of the following are used to protect organisms from the toxic by-products of
oxygen EXCEPT
A)
carotenoids.
B)
superoxide dismutase.
C)
peroxidase.
D)
protease.
E)
catalase.
E.
obligate anaerobe
A
microbe that grows only at the bottom of a tube of thioglycollate medium is
probably a(n)
A)
obligate aerobe.
B)
facultative anaerobe.
C)
aerotolerant anaerobe.
D)
microaerophile.
E)
obligate anaerobe.
E)
only a few microbes can extract it from the atmosphere, but all organisms
require it for amino acid and nucleotide synthesis
Nitrogen
is a growth limiting nutrient for many organisms because
A)
it is necessary for the biosynthesis of amino acids.
B)
it is required for synthesis of nucleotides.
C)
it is required for lipid synthesis.
D)
only a small number of bacteria are able to extract it from the atmosphere.
E)
only a few microbes can extract it from the atmosphere, but all organisms
require it for amino acid and nucleotide synthesis.
A.
heme
Which
of the following growth factors would NOT be required by microbes which do not
utilize electron transport chains?
A)
heme.
B)
selenium.
C)
NADH.
D)
vitamins.
E)
amino acids.
E) hydrogen bonds
are broken, proteins are denatured, and membranes become too fluid.
At
temperatures higher than the maximum growth temperature for an organism,
A)
proteins are permanently denatured.
B)
membranes become too fluid for proper function.
C)
hydrogen bonds within molecules are broken.
D)
hydrogen bonds are broken, and proteins are permanently denatured.
E)
hydrogen bonds are broken, proteins are denatured, and membranes become too
fluid.
C) mesophiles.
Human
pathogens are classified as
A)
thermoduric.
B)
thermophiles.
C)
mesophiles.
D)
hyperthermophiles.
E)
psychrophiles.
A.
hydrostatic pressure
The
term barophile refers to which of the following growth
requirements?
A)
hydrostatic pressure
B)
temperature
C)
nitrogen source
D)
pH
E)
osmotic pressure
C) an acidophile
Which
of the following organisms would be most likely to contaminate a jar of
pickles?
A)
a neutrophile
B)
a thermophile
C)
an acidophile
D)
an obligate anaerobe
E)
a mesophile
E. either facultative
anaerobes or aerotolerant anaerobes.
Organisms
that can grow with or without oxygen present are
A)
obligate aerobes.
B)
facultative anaerobes.
C)
aerotolerant anaerobes.
D)
obligate anaerobes.
E)
either facultative anaerobes or aerotolerant anaerobes.
C.
enriched media
A
fastidious organism might be grown on which of the following types of media?
A)
transport media
B)
reducing media
C)
enriched media
D)
differential media
E)
selective media
A. in
a reducing medium
Obligate
anaerobes may be cultured in the laboratory
A)
in a reducing medium.
B)
in a candle jar.
C)
in standard Petri plates.
D)
on blood agar plates.
E)
on blood agar plates in a candle jar.
D.
enrichment culture
Joan
wants to discover a microbe capable of degrading an environmental contaminant.
Which of the following refers to the process she should use?
A)
cell culture
B)
chemostat
C)
quorum sensing
D)
enrichment culture
E)
nitrogen fixation
B. 7
hours
A
microbiologist inoculates a growth medium with 100 bacterial cells/ml. If the
generation time of the species is 1 hour, and there is no lag phase, how long
will it be before the culture contains more than 10,000 cells/ml?
A)
24 hours
B)
7 hours
C)
2 hours
D)
3 hours
E)
10 hours
D.
inoculation of cell cultures
An
epidemiologist is investigating a new disease and observes what appear to be
bacteria inside tissue cells in clinical samples from victims. The scientist
wants to try to isolate the bacteria in the lab. What culture conditions are
most likely to be successful?
A)
culturing on blood agar plates
B)
inoculation of EMB plates
C)
incubation in a candle jar
D)
inoculation of cell cultures
E)
inoculation of a minimal medium broth
microscopic
counts
Which
of the following measurement techniques would be useful to quantify a species
of bacteria that is difficult to culture?
A)
membrane filtration
B)
viable plate counts
C)
MPN
D)
microscopic counts
E)
metabolic activity
d.
both a differntial and selective
MacConkey
agar plates represent __________ medium.
A)
a minimal
B)
a selective
C)
a differential
D)
both a differential and a selective
E)
both a minimal and a selective
A) a glass slide
containing an etched grid for counting microbes directly using a microscope.
A
Petroff-Hauser counting chamber is
A)
a glass slide containing an etched grid for counting microbes directly using a
microscope.
B)
a device that counts cells as they interrupt an electrical current.
C)
a device that measures the amount of light that passes through a culture.
D)
an apparatus that traps bacterial cells on a membrane filter where they can be
counted.
E)
a device used to count numbers of bacterial colonies on a Petri plate.
Answer: A
B.
exponential growth
Another
term for the logarithmic growth of bacterial cells is
A)
generation time.
B)
exponential growth.
C)
arithmetic growth.
D)
absorbance.
E)
binary fission.
E.
Chemostat
A
device that removes wastes and adds fresh medium to bacterial cultures in order
to prolong the log phase of a culture is called a(n)
A)
Coulter counter.
B)
cytometer.
C)
spectrophotometer.
D)
pellicle.
E)
chemostat.
C.
30,000
A
specimen of urine is determined to contain 30 bacterial cells per microliter.
How many cells would be present in a milliliter?
A)
3
B)
300
C)
30,000
D)
3,000
E)
30 million
B.
turbidity
Which
of the following is NOT a direct method for measuring the number of microbes in
a sample?
A)
viable plate counts
B)
turbidity
C)
Coulter counter
D)
MPN
E)
membrane filtration
B.
log phase
During
which growth phase are bacteria more susceptible to antimicrobial drugs?
A)
lag phase
B)
log phase
C)
stationary phase
D)
death phase
E)
the susceptibility is the same for all phases
B.
osmotic pressure
The
use of salt and sugar in preserving various types of foods is an application of
which of the following concepts?
A)
nitrogen fixation
B)
osmotic pressure
C)
pH
D)
hydrostatic pressure
E)
quorum sensing
E.
the lungs
A
clinical sample labeled as "sputum" was collected from
A)
the skin.
B)
the blood.
C)
the central nervous system.
D)
a piece of tissue.
E)
the lungs.
C.
steak plate technique
The
method of obtaining isolated cultures that utilizes surface area to dilute
specimens is called
A)
the pour-plate technique.
B)
serial dilution.
C)
the streak-plate technique.
D)
transport media.
E)
enrichment culturing.
D.
biofilms
__________
are complex communities of various types of microbes that adhere to surfaces.
A)
Aggregates
B)
Colonies
C)
Isolates
D)
Biofilms
E)
Media
b.
that produces one colony
A
colony-forming unit is the number of cells
A)
in a colony.
B)
that produces one colony.
C)
in a particular specimen.
D)
that is in exponential phase in a culture.
E)
that can be placed on a Petri plate.
A.
hydrogen peroxide
All
of the following ingredients might be found in complex media EXCEPT
A)
hydrogen peroxide.
B)
yeast extract.
C)
blood.
D)
soy extract.
E)
milk proteins.
D.
reducing media
Sodium
thioglycollate is associated with which of the following types of media?
A)
transport media
B)
differential media
C)
complex media
D)
reducing media
E)
selective media
C.
metabolic activity
Which
of the following quantification techniques can distinguish living cells from
dead cells in a culture?
A)
microscopic counts
B)
dry weight
C)
metabolic activity
D)
a Coulter counter
E)
turbidity
D.
stationary phase
during
the __________ of growth, new cells are being produced at the same rate as
other cells are dying.
A)
lag phase
B)
log phase
C)
death phase
D)
stationary phase
E)
intermediate phase
A.
death phase
During
the __________ of growth, cells are dying faster than new cells are being
produced.
A)
death phase
B)
lag phase
C)
log phase
D)
stationary phase
E)
longitudinal phase
C.
lag phase
When
cells are metabolically active but not dividing, they are in the
A)
stationary phase.
B)
log phase.
C)
lag phase.
D)
death phase.
E)
exponential phase.
B.
log phase
Metabolic
activity is at maximum level in the __________ of growth.
A)
lag phase
B)
log phase
C)
death phase
D)
stationary phase
E)
intermediate phase
C.
log phase
Cells
are rapidly growing and dividing during the __________ of growth.
A)
death phase
B)
lag phase
C)
log phase
D)
stationary phase
E)
indeterminate phase
B.
salt concentrations
An
organism that tolerates high __________ is called a halophile.
A)
hydrostatic pressure
B)
salt concentrations
C)
pH
D)
carbon dioxide levels
E)
oxygen levels
A.
carbon dioxide levels
A
capnophile is a microorganism that thrives in conditions of high __________.
A)
carbon dioxide levels
B)
hydrostatic pressure
C)
oxygen levels
D)
pH
E)
salt concentration
C.
hydrostatic pressure
A
microorganism found living under conditions of high __________ is a barophile.
A)
pH values
B)
oxygen concentrations
C)
hydrostatic pressure
D)
carbon dioxide levels
E)
salt concentrations
d.
oxygen levels
Microaerophiles
are microbes that grow best at low
A)
carbon dioxide levels.
B)
pH values.
C)
hydrostatic pressure.
D)
oxygen levels.
E)
salt concentrations.
E. pH
An
acidophile thrives under conditions of low
A)
carbon dioxide levels.
B)
salt concentrations.
C)
oxygen levels.
D)
hydrostatic pressure.
E)
pH.
FALSE
Obligate
anaerobes have enzymes such as superoxide dismutase to protect them from the
damaging effects of oxygen.
TRUE
OR FALSE?
FALSE
Nitrogen
fixation is a process that occurs in all bacteria.
TRUE
OR FALSE?
TRUE
Thermoduric
mesophiles are often responsible for spoilage of improperly canned foods.
TRUE
OR FALSE
TRUE
An
obligate halophile will burst if placed in freshwater.
TRUE
OR FALSE
FALSE
The
only effective way to store bacterial cultures for short periods of time is to
arrest their metabolism by freezing.
TRUE
OR FALSE?
TRUE
Quorum
sensing is a process by which bacteria respond to the density of other bacteria
in their environment.
Answer: TRUE
OR FALSE?
FALSE
An
obligate anaerobe can be cultured in a candle jar.
Answer:
TRUE OR FALSE
FALSE
Agar
is a useful compound in the microbiology lab because it is an excellent
nutrient for bacteria.
Answer: FALSE
OR TRUE
TRUE
A
selective medium can be formulated either by including inhibitory chemical
substances or by leaving out a single crucial nutrient.
Answer: TRUE
OR FLASE
TRUE
In
spectrophotometry, 40% light transmission is the same thing as 60% absorbance
of light.
Answer: TRUE
OR FALSE
fixation
The
conversion of nitrogen gas to ammonia is called nitrogen __________.
chemoheterotrophs
Organisms
that require organic sources of carbon and energy are called __________.
superoxide
The
__________ radical is formed during the incomplete reduction of O2 during
electron transport in aerobes.
optimum
The
__________ growth temperature is the temperature at which an organism exhibits
the highest growth rate.
mesophiles
Bacteria
that thrive at human body temperatures are classified as __________.
11.5
Alkalinophiles
can survive in water up to pH __________. (Be sure your answer is a numeral.)
crenation
Cells
that are exposed to hypertonic environments will exhibit __________.
inoculum
A(n)
__________ is a sample of microorganisms introduced into a growth medium.
colony
A
pure culture is composed of cells that arise from a single __________.
agar
A
gelling agent derived from algae that is useful for creating solid growth media
is called __________.
lag
A
sample placed into fresh medium is typically initially in the __________ phase
of microbial growth.
number
A
growth curve plots the __________ of organisms in a growing population over
time.
cytometry
Flow
__________ is a method of counting cells that have been stained or tagged with
fluorescent dyes.
pellicle
A
film of cells at the surface of a broth is called a(n) __________.
spectrophotometer
A(n)
__________ can measure changes in the turbidity of a bacterial culture.
C.
prions
Standard
methods of sterilization are not effective in inactivating
A)
viruses.
B)
bacterial cells.
C)
prions.
D)
bacterial endospores.
E)
fungi.
D) Disinfectants
are used on inanimate surfaces.
Which
of the following statements is true of disinfectants?
A)
Disinfectants are effective in destroying endospores.
B)
Disinfectants are used on living tissue.
C)
Disinfectants are used for sterilization.
D)
Disinfectants are used on inanimate surfaces.
E)
Disinfectants are only effective for short periods of time (seconds to
minutes).
E) It is not an
effective means of evaluating the efficacy of antimicrobial agents.
Which
of the following statements concerning microbial death is FALSE?
A)
It can be used to evaluate the efficacy of antimicrobial agents.
B)
It is constant over time of exposure to an antimicrobial agent.
C)
It is the permanent loss of a microbe's reproductive ability.
D)
It is the permanent loss of a microbe's ability to reproduce and can be used to
evaluate antimicrobial agents.
E)
It is not an effective means of evaluating the efficacy of antimicrobial
agents.
A.A
public toilet is treated with disinfectants
Which
of the following is an example of sanitization?
A)
A public toilet is treated with disinfectants.
B)
A surgeon washes her hands before surgery.
C)
Heat is used to kill potential pathogens in apple juice.
D)
An autoclave is used to prepare nutrient agar.
E)
A nurse prepares an injection site with an alcohol swab.
E.
free of pathogens
Aseptic means
A)
sterile.
B)
free of all microbes.
C)
clean.
D)
sanitized.
E)
free of pathogens.
D.
autoclaving
Which
of the following would NOT be bacteriostatic?
A)
desiccation
B)
freezing below 0°C
C)
lyophilization
D)
autoclaving
E)
refrigeration of mesophiles
E.
protein synthesis
Antimicrobial
agents that damage nucleic acids also affect
A)
the cell wall.
B)
the cell membrane.
C)
the viral envelope.
D)
endospores.
E)
protein synthesis.
A.
enveloped viruses
Seventy
percent alcohol is effective against
A)
enveloped viruses.
B)
nonenveloped viruses.
C)
bacterial endospores.
D)
protozoan cysts.
E)
prions.
b.
low-level germicide
An
instrument that will come into contact with only the skin of a patient should
be disinfected with a(n)
A)
high-level germicide.
B)
low-level germicide.
C)
intermediate-level germicide.
D)
degerming agent only.
E)
germistatic agent only.
C.
lyophilization
Which
of the following is NOT an effective means of sterilization?
A)
ionizing radiation
B)
incineration
C)
lyophilization
D)
autoclaving
E)
dry heat
B.
heating at 72°C for 15 seconds
Which
of the following describes flash pasteurization?
A)
heating at 63°C for 30 minutes
B)
heating at 72°C for 15 seconds
C)
heating at 72°C for 15 minutes
D)
heating at 134°C for one second
E)
passing liquid through steam at 140°C
D. UHT
sterilization
The
dairy creamer used in restaurants is usually sterilized by
A)
filtration.
B)
ionizing radiation.
C)
lyophilization.
D)
UHT sterilization.
E)
autoclaving.
E) both growing
bacteria and enveloped viruses.
Boiling
water for 10 minutes is effective in ridding it of
A)
actively growing bacteria.
B)
enveloped viruses.
C)
bacterial endospores.
D)
protozoan cysts.
E)
both growing bacteria and enveloped viruses.
C) varying
thicknesses of membrane filters used
Which
of the following is NOT a feature associated with filtration?
A)
nitrocellulose or plastic membrane filters
B)
sterilization of heat-sensitive materials
C)
varying thicknesses of membrane filters used
D)
use of HEPA filters to filter air
E)
ability of some filters to trap viruses and proteins
E.
Brucella melitensis
Which
of the following is a target of pasteurization?
A) Bacillus
stearothermophilus
B) Clostridium
botulinum
C) Neisseria
gonorrhoeae
D) Chlamydia
trachomatis
E) Brucella
melitensis
A.
ultraviolet rays
Which
of the following types of radiation is nonionizing and has the shortest
wavelength?
A)
ultraviolet light
B)
infrared radiation
C)
microwaves
D)
X rays
E)
gamma rays
E.
gamma rays
Which
of the following is used for microbial control in fresh fruits and vegetables?
A)
X rays
B)
ultraviolet light
C)
electron beams
D)
microwaves
E)
gamma rays
D.
both HEPA fileters and ultraviolet light
Which
of the following can be used to disinfect air?
A)
HEPA filters
B)
ethylene oxide
C)
ultraviolet light
D)
both HEPA filters and ultraviolet light
E)
both ethylene oxide and ultraviolet light
B.
phenolics
Lysol
is an example of which of the following groups of chemical antimicrobial
agents?
A)
halogens
B)
phenolics
C)
alcohols
D)
aldehydes
E)
surfactants
D)
methicillin-resistant Staphylococcus aureus (MRSA), BSL-2
Which
of the following is the most appropriate pairing of microbe and biosafety
level?
A) E.
coli, BSL-3
B)
anthrax, BSL-1
C)
Ebola, BSL-2
D)
methicillin-resistant Staphylococcus aureus (MRSA), BSL-2
E)
tuberculosis, BSL-1
C.
halogens
Betadine
is an example of which of the following groups of antimicrobial agents?
A)
alcohols
B)
heavy metals
C)
halogens
D)
phenolics
E)
surfactants
D.
they function by cross-linking proteind
Which
of the following statements about quaternary ammonium compounds is FALSE?
A)
They are a type of detergent.
B)
Zephiran is an example of a quat.
C)
They are not effective against Pseudomonas aeruginosa.
D)
They function by cross-linking proteins.
E)
They are harmless to humans except at high concentrations.
C. peracetic
acid
Which
of the following is a sterilizing agent?
A)
ozone
B)
hydrogen peroxide
C)
peracetic acid
D)
dish soap
E)
ozone and hydrogen peroxide
E.
silver nitrate
Which
of the following was used in the past to prevent the transmission of gonorrhea
from an infected mother to her newborn?
A)
hydrogen peroxide
B)
beta-propiolactone
C)
thimerosal
D)
hexachlorophene
E)
silver nitrate
A.
ethylene oxide
Which
of the following is used to sterilize items that should not, or cannot, be
exposed to heat or water?
A)
ethylene oxide
B)
formaldehyde
C)
hydrogen peroxide
D)
calcium hypochlorite
E)
triclosan
A.
they are used only to preserve dead tissues
Which
of the following statements about aldehydes is FALSE?
A)
They are used only to preserve dead tissues.
B)
They denature proteins.
C)
Some aldehydes can sterilize after long periods of exposure.
D)
They are usually hazardous to humans.
E)
They are used in aqueous solutions.
B.
antimicrobials
Disinfecting
agents naturally produced by microorganisms are
A)
aldehydes.
B)
antimicrobials.
C)
halogens.
D)
quats.
E)
triclosans.
B.
germicide
A
chemical agent that kills pathogenic microbes in general is a(n)
A)
sanitizer.
B)
germicide.
C)
disinfectant.
D)
fungicide.
E)
antiseptic.
D. it
only arrests growth of vegetative cells.
Which
of the following is NOT a desirable characteristic of an ideal antimicrobial
agent?
A) it
is inexpensive.
B) it
is stable during storage.
C) it
is harmless to humans.
D) it
only arrests growth of vegetative cells.
E) it
acts quickly.
C) Bacillus
stearothermophilus
The
endospores of which of the following microbes are used to measure the
effectiveness of autoclave sterilization?
A) Clostridium
botulinum
B) Neisseria
gonorrhoeae
C) Bacillus
stearothermophilus
D) Pseudomonas
aeruginosa
E) Mycobacterium
bovis
b.
filtration
A
scientist develops a new medication that is a protein compound and that must be
administered by injection. Which of the following would be the most effective
and safest means of preparing a sterile solution of the new medication?
A)
autoclaving
B)
filtration
C)
dilution with alcohol
D)
lyophilization
E)
ultraviolet irradiation
A.
use-dilution test
Which
of the following procedures is currently the standard test used in the United
States for evaluating the efficiency of antiseptics and disinfectants?
A)
use-dilution test
B)
microbial death rate
C)
in-use test
D)
thermal death point
E)
phenol coefficient
C.
ethylene oxide
Which
of the following would be used to sterilize a mattress?
A)
autoclaving
B)
formaldehyde
C)
ethylene oxide
D)
heavy metals
E)
radiation
E.
both alcohol and phenolics
Disinfectants
that damage membranes include
A)
alcohol.
B)
phenolics.
C)
iodine.
D)
hydrogen peroxide.
E)
both alcohol and phenolics.
B.
ethylene oxide
Which
of the following antimicrobial agents is the most toxic to humans?
A)
70% alcohol
B)
ethylene oxide
C)
quats
D)
chloramines
E)
iodophors
B.
sterilizing method
The
process of filtration is a(n)
A)
disinfectant method.
B)
sterilizing method.
C)
sanitization method.
D)
antiseptic procedure.
E)
ineffective method for removing microbes.
D.
disinfecting and sterlizing agent
Hydrogen
peroxide is a(n)
A)
sterilizing agent.
B)
disinfecting agent.
C)
antiseptic.
D)
disinfecting and sterilizing agent.
E)
ineffective method of disinfecting.
A.
sterilization
The
process of incineration is used for
A)
sterilization.
B)
disinfection.
C)
sanitization.
D)
both disinfection and sanitization.
E)
degerming.
E.
both antisepsis and disinfection.
Alcohols
are used for
A)
disinfection.
B)
sterilization.
C)
antisepsis.
D)
both sterilization and disinfection.
E)
both antisepsis and disinfection.
B.
disinfection
The
chemical agents known as "quats" are used for
A)
antisepsis.
B)
disinfection.
C)
sterilization.
D)
quantifying antimicrobial activity.
E)
neither antisepsis nor disinfection.
B.
sterilization
The
compound ethylene oxide is used in
A)
sanitization.
B)
sterilization.
C)
antisepsis.
D)
degerming.
E)
disinfection.
E) both
disinfection and sterilization.
Glutaraldehyde
is used for
A)
antisepsis.
B)
disinfection.
C)
sterilization
D)
sanitization.
E)
both disinfection and sterilization.
A.
disinfection
__________
may be achieved using chlorine dioxide.
A)
Disinfection
B)
Sterilization
C)
Degerming
D)
Antisepsis
E)
Both antisepsis and degerming
A.
sterilization
Gamma
irradiation is a process for
A)
sterilization.
B)
disinfection.
C)
antisepsis.
D)
degerming.
E)
both antisepsis and disinfection.
E) Both
disinfection and sanitization
__________
can be accomplished using boiling water.
A)
Sanitization
B)
Disinfection
C)
Sterilization
D)
Antisepsis
E)
Both disinfection and sanitization
true
An
environment may contain some microbes and still be considered sterile.
true
Some
viruses are inactivated by the same chemical or physical agents that damage
cytoplasmic membranes.
false
UV
light has the most effect on protein structure.
false
Antimicrobial
agents usually work best at high temperatures and pH levels.
false
The
phenol coefficient is one of the most widely used measurements of an
antimicrobial agent's effectiveness.
false
No
chemical or antimicrobial agents inactivate prions.
false
The
decimal reduction time is the time required to kill all the microbes in a given
sample.
true
Slow
freezing is more damaging to microbial cells than quick freezing.
false
Hydrogen
peroxide is an effective antiseptic.
true
By
themselves, soaps have only degerming activity, not antimicrobial activity.
lyophilization
The
process of freeze-drying microbes to preserve them is __________.
phenolics
Natural
antiseptics such as pine or clove oil are examples of antimicrobial compounds
called __________.
iodophor
A(n)
__________ is an iodine-containing organic compound found in such antiseptics
as Betadine.
aldehydes
Disinfectants
known as __________ have the chemical group -CHO, which reacts with and damages
both proteins and nucleic acids.
thermal
The
lowest temperature that kills all cells in a broth in 10 minutes is knows as
the __________ death point.
less
The
amount of time needed to sterilize materials using moist heat is __________
than the time needed to sterilize using dry heat.
autoclave
A(n)
__________ is an instrument that sterilizes by exposing materials to steam
under pressure.
contaiment
BSL-4
is the appropriate __________ level when handling highly contagious deadly
microbes.
less
Ultraviolet
light penetrates __________ effectively than gamma rays.
phenolic
Triclosan
is a(n) __________ antimicrobial compound that has been incorporated into
consumer items such as garbage bags and diapers.
halogens
Elements
such as iodine, chlorine, and bromine are examples of __________, which are the
basis for many effective antimicrobial agents.
proteins
Heavy
metal and oxidizing agent disinfectants damage __________, interfering with
microbial metabolism.
osmotic
The
use of high levels of salt or sugar in the preservation of food relies on the
phenomenon of __________ pressure.
pasteurization
The
process of heating milk or fruit juice to levels that kill any pathogenic
microbes present is known as __________.
endospores
Sterilization
procedures generally focus on inactivating or eliminating bacterial __________.
E) Streptomyces.
A
large percentage of antibiotics and semisynthetic drugs are produced by members
of the genus
A) Cephalosporium.
B) Penicillium.
C) Bacillus.
D) Mycobacterium.
E) Streptomyces.
A.
cells become more suseptiable to osmotic pressure
An
antimicrobial that inhibits cell wall synthesis will result in which of the
following?
A)
Cells become more susceptible to osmotic pressure.
B)
Cells cannot attach to their hosts.
C)
Ribosomes lose their function.
D)
The sterols in the cell wall become nonfunctional.
E)
The replication of cells, including cancer cells, slows down.
B.
bacterial cells
Beta-lactam
antibiotics have an effect on which of the following types of cells?
A)
animal cells
B)
bacterial cells
C)
fungal cells
D)
virus-infected cells
E)
both animal and fungal cells
C)
They have a broader spectrum of action
Which
of the following is a primary advantage of semisynthetic drugs?
A)
They are less stable and consequently have fewer side effects.
B)
They work faster.
C)
They have a broader spectrum of action.
D)
They must be administered intravenously.
E)
They are not readily absorbed, so they persist longer.
D) isoniazid
Which
of the following drugs specifically targets cell walls that contain arabinogalactan-mycolic
acid?
A)
vancomycin
B)
penicillin
C)
methicillin
D)
isoniazid
E)
bacitracin
B.
erythromycin
Which
of the following antibiotics disrupts cytoplasmic membrane function?
A)
streptomycin
B)
erythromycin
C)
tetracycline
D)
penicillin
E)
amphotericin B
B.
interference with alanine-alanine bridges
Which
of the following is NOT a target of drugs that inhibit protein synthesis?
A)
the shape of the 30S ribosomal subunit
B)
interference with alanine-alanine bridges
C)
the enzymatic site of the 50S ribosomal subunit
D)
movement of the ribosome from one codon to the next
E)
the tRNA docking site
E.
waksman
Which
scientist coined the term antibiotic?
A)
Fleming
B)
Domagk
C)
Kirby
D)
Ehrlich
E)
Waksman
D.
antiviral
The
most limited group of antimicrobial agents is the __________ drugs.
A)
antibacterial
B)
antifungal
C)
anthelmintic
D)
antiviral
E)
antiprotozoan
C.
diffusion susceptanility test
Another
term for the Kirby-Bauer test is the
A)
minimum inhibitory concentration test.
B)
E test.
C) diffusion
susceptibility test.
D)
minimum bactericidal concentration test.
E)
broth dilution test.
B) The larger the
zone, the more resistant the organism is.
Which
of the following statements about the zone of inhibition is FALSE?
A)
It is measured as a diameter.
B)
The larger the zone, the more resistant the organism is.
C)
It is a clearing zone with no growth.
D)
It is a result of diffusion of the drug out of the paper disk.
E)
It is measured after incubation.
D..
tetracyclines
Which
of the following groups of drugs can become incorporated into the bones and
teeth of a fetus?
A)
beta-lactams
B)
aminoglycosides
C)
quinolones
D)
tetracyclines
E)
sulfonamides
E) both
pseudomembranous colitis and thrush
Which
of the following can result when antibiotic therapy disrupts the normal
microbiota?
A)
anaphylactic shock
B)
black hairy tongue
C)
pseudomembranous colitis
D)
thrush
E)
both pseudomembranous colitis and thrush
C)
Resistant cells grow more efficiently and quickly than susceptible cells.
Which
of the following statements concerning development of antibiotic resistance is
FALSE?
A)
It is often mediated by R-plasmids.
B)
Resistant cells are normally in the minority in a bacterial population.
C)
Resistant cells grow more efficiently and quickly than susceptible cells.
D)
New resistance genes can be gained through transformation, transduction, or
conjugation.
E)
Resistance can occur through mutation of existing bacterial genes.
Answer:
B) inactivation of
the drug
β-lactamase
production is an example of which of the following types of resistance?
A)
alteration of the target of the drug
B)
inactivation of the drug
C)
change in the permeability of the drug
D)
overproduction of an enzyme in a key metabolic pathway
E)
removal of the drug via a pump
E) are an
alternative to the use of chemotherapy involving microbial antagonism.
Probiotics
A)
involve microbial antagonism.
B)
are an alternative to the use of chemotherapy.
C)
involve the use of extracts from microorganisms.
D)
is a term for resistance to antibiotics.
E)
are an alternative to the use of chemotherapy involving microbial antagonism.
A) preventing the
cross-linkage of NAM subunits.
Most
drugs that inhibit the synthesis of the cell wall act by
A)
preventing the cross-linkage of NAM subunits.
B)
blocking the secretion of cell wall molecules from the cytoplasm.
C)
preventing the formation of alanine-alanine bridges.
D)
disrupting the formation of the mycolic acid layer of the cell wall.
E)
preventing the formation of β-lactamases.
B.
inhibiting protein synthesis
Most
broad-spectrum antibiotics act by
A)
inhibiting the synthesis of the cell wall.
B)
inhibiting protein synthesis.
C)
inhibiting nucleic acid synthesis.
D)
inhibiting metabolic pathways.
E)
disrupting the cytoplasmic membrane.
E) both fluconazole
and turbinafine
Which
of the following antifungals works by inhibiting ergosterol synthesis?
A)
fluconazole
B)
turbinafine
C)
amphotericin B
D)
nystatin
E)
both fluconazole and turbinafine
E) were the first
widely used antimetabolic antimicrobial and indirectly inhibit nucleic acid
synthesis.
Sulfonamides
A)
are antimetabolic drugs.
B)
were the first widely used antimicrobial drugs.
C)
indirectly inhibit the synthesis of nucleic acids.
D)
are no longer widely used.
E)
were the first widely used antimetabolic antimicrobial and indirectly inhibit
nucleic acid synthesis.
B) the conversion
of PABA to dihydrofolic acid
Which
of the following pathways is specifically inhibited by sulfonamides?
A)
the conversion of tetrahydrofolic acid to PABA
B)
the conversion of PABA to dihydrofolic acid
C)
the conversion of dihydrofolic acid to tetrahydrofolic acid
D)
the conversion of PABA to tetrahydrofolic acid
E)
the conversion of dihydrofolic acid to PABA
A.
quinolones
Which
of the following drugs inhibits nucleic acid synthesis specifically in prokaryotes?
A)
quinolones
B)
actinomycin
C)
rifampin
D)
tetracycline
E)
5-fluorocytosi
C.)
synergism
The
cooperative activity of drugs such as beta-lactam antibiotics and clavulanic
acid, a β-lactamase inhibitor, is known as
A)
cross resistance.
B)
antimetabolism.
C)
synergism.
D)
selective toxicity.
E)
chemotherapy
B.
porins
Alterations
in the structure of which of the following are an important aspect of
Gram-negative bacterial resistance to antimicrobial drugs?
A)
plasmids
B)
porins
C)
mitochondria
D)
cytoplasmic membrane
E)
ribosomes
D) these diseases
are caused by viruses.
It
is inappropriate to prescribe antibacterial agents to treat colds or flu
because
A)
the microbes involved can develop resistance rapidly.
B)
these diseases are transmitted by endospores, which are hard to kill.
C)
these diseases exhibit cross resistance.
D)
these diseases are caused by viruses.
E)
these diseases can act synergistically with each other.
A) Domagk
Who
discovered the first widely available antibiotic?
A)
Domagk
B)
Ehrlich
C)
Fleming
D)
Waksman
E)
Ehrlich and Waksman
Selective
Toxicity
A drug that kills harmful microbes without damaging the host
B) antisense
nucleic acids.
Antimicrobials
that block protein synthesis by binding to the mRNA are
A)
aminoglycosides.
B)
antisense nucleic acids.
C)
macrolides.
D)
beta-lactams.
E)
nucleic acid analogs.
D) both
susceptibility and MIC
The
Etest determines which of the following?
A)
susceptibility
B)
MBC
C)
MIC
D)
both susceptibility and MIC
E)
both MBC and MIC
C.
their activity against cell walls
Which
of the following is NOT a criterion by which all antimicrobial agents can be evaluated?
A)
their spectrum of action
B)
their efficacy
C)
their activity against cell walls
D)
their route of administration
E)
their safety
E) both cycloserine
and vancomycin
Which
of the following interferes with cell wall synthesis by blocking alanine bridge
formation?
A)
beta-lactams
B)
cycloserine
C)
bacitracin
D)
vancomycin
E)
both cycloserine and vancomycin
C) preventing virus
attachment.
Antimicrobial
sugar analogs are effective for
A)
preventing bacterial protein synthesis.
B)
preventing cell membrane synthesis.
C)
preventing virus attachment.
D)
preventing nucleic acid synthesis.
E)
blocking a metabolic pathway.
B.
lack of turbidity
Which
of the following is a measurement associated with the broth dilution test?
A)
the zone of inhibition
B)
lack of turbidity
C)
cell lysis
D)
lack of turbidity and zone of inhibition
E)
presence of turbidity and cell lysis
D.
brain
)
Infection of the __________ would be the hardest to treat with antimicrobial
drugs.
A)
heart
B)
kidneys
C)
liver
D)
brain
E)
colon
E) Candida
albicans and Clostridium difficile
Answer: E
Disruption
of the normal microbiota can result in infections caused by which of the
following microbes?
A) Mycobacterium
B) Candida
albicans
C) Clostridium
difficile
D)
both Mycobacterium and Clostridium difficile
E) Candida
albicans and Clostridium difficile
C) inhibiting
nucleic acid synthesis.
The
antimicrobials called quinolones act by
A)
disrupting cytoplasmic membranes.
B)
inhibiting cell wall synthesis.
C)
inhibiting nucleic acid synthesis.
D)
inhibiting a metabolic pathway.
E)
inhibiting protein synthesis.
D)
disrupts cytoplasmic membranes
Amphotericin
B is an antifungal drug that
A)
inhibits protein synthesis.
B)
inhibits nucleic acid synthesis.
C)
blocks a metabolic pathway.
D)
disrupts cytoplasmic membranes.
E)
inhibits cell wall synthesis.
B) inhibition of
cell wall synthesis.
The
mechanism of action of the antibiotic vancomycin is
A)
inhibition of protein synthesis.
B)
inhibition of cell wall synthesis.
C)
inhibition of nucleic acid synthesis.
D)
inhibition of a metabolic pathway.
E)
disruption of cytoplasmic membranes
A.
protein synthesis
The
tetracyclines interfere with
A)
protein synthesis.
B)
cell wall synthesis.
C)
cell membrane component synthesis.
D)
nucleic acid synthesis.
E)
folic acid synthesis.
D) inhibit
metabolic pathways.
Trimethoprim
is an example of antimicrobials that
A)
disrupt cytoplasmic membranes.
B)
inhibit cell wall synthesis.
C)
inhibit nucleic acid synthesis.
D)
inhibit metabolic pathways.
E)
inhibit protein synthesis.
A) inhibition of
protein synthesis.
The
mechanism of action of erythromycin is
A)
inhibition of protein synthesis.
B)
inhibition of cell wall synthesis.
C)
inhibition of nucleic acid synthesis.
D)
inhibition of a metabolic pathway.
E)
disruption of cytoplasmic membranes.
B) inhibit cell
wall synthesis.
Methicillin
is an example of the beta-lactam class of drugs that
A)
disrupt cytoplasmic membranes.
B)
inhibit cell wall synthesis.
C)
inhibit nucleic acid synthesis.
D)
inhibit metabolic pathways.
E)
inhibit protein synthesis.
D) nucleic acid
synthesis.
Ribavirin
is an antiviral that interferes with
A)
protein synthesis.
B)
cell wall synthesis.
C)
cell membrane component synthesis.
D)
nucleic acid synthesis.
E)
viral attachment.
D.
disrupts cytoplasmic membranes
The
antimicrobial polymyxin
A)
inhibits protein synthesis.
B)
inhibits nucleic acid synthesis.
C)
blocks a metabolic pathway.
D)
disrupts cytoplasmic membranes.
E)
inhibits cell wall synthesis.
A) inhibition of
metabolic pathways.
The
mechanism of action of sulfonamides is
A)
inhibition of metabolic pathways.
B)
inhibition of cell wall synthesis.
C)
inhibition of nucleic acid synthesis.
D)
disruption of cytoplasmic membranes.
E)
inhibition of protein synthesis.
false
Paul
Erhlich coined the term antibiotics for the "magic
bullet" antimicrobials he pursued
true
Antisense
nucleic acids are designed to have no side effects against humans.
false
Beta-lactam
drugs act by inhibiting formation of the cytoplasmic membrane.
false
Because
all cells engage in protein synthesis, there are few antimicrobial drugs that
selectively inhibit this process.
true
Many
antimicrobial drugs that affect the cytoplasmic membrane are used only
externally because they can be toxic to humans.
true
Some
bacterial cells are resistant to a variety of antimicrobials because they
actively pump the drugs out of the cell.
false
The
outer membrane of Gram-negative bacteria enables many antimicrobial drugs to
enter the cell more easily.
false
If
a subculture of an MIC test grows in an MBC test, the concentration of the drug
was bactericidal.
true
Brain
and spinal cord infections are difficult to treat because most antimicrobial
drugs cannot diffuse out of the blood into these organs.
true
Organs
that are commonly affected by drug toxicity include the kidneys and the liver
chemotherapeutic
Any
drug that acts against a disease is called a(n) __________ agent.
toxicity
Selective
__________ means that a given antimicrobial agent is more toxic to a pathogen
than to the host being treated.
analogs
Nucleotide
or nucleoside __________are antimicrobial agents that mimic the chemical
structure of DNA building blocks.
drug
A
broad-spectrum __________ is effective against a wide variety of pathogens.
Superinfections
Secondary
infections that result from the killing of the normal microbiota are called
__________.
antagonism
Competition
between beneficial microbes and potential pathogens is called microbial
__________.
bacteriostatic
A(n)
__________ concentration of a drug is one at which microbes survive but are not
able to grow and reproduce.
extrachromosomal
R-plasmids
are __________ pieces of DNA that promote horizontal transfer of genes among
bacteria and contribute to the spread of antimicrobial resistance.
cross
Some
bacteria develop resistance to groups of drugs because the drugs are all
structurally similar to each other; this is a phenomenon known as __________
resistance.
resistance
Second-generation
drugs are semisynthetic drugs developed to combat __________ against an
existing drug.
antagonistic
Drugs
that slow down bacterial growth would be __________ to penicillin.
topical
External
infections can be treated by __________ administration, in which a drug is
applied directly to the site of infection.
Pleomorphic bacteria
vary in size and shape.
Gram(-): Rickettsiae and Chlamydiae (Giemsa)
palisades
Which of the following bacterial arrangements is the result of snapping division?
gram negative
Which of the following is NOT associated with Corynebacterium?
cytoplamic membrane
What bacterial structure is responsible for separating the daughter DNA molecules after replication?
Endospores
can be produced when nutrients are scarce.
Bergey's Manual contains
classification schemes for prokaryotes.
