Microbiology
Select the structures below that are found in all bacterial cells:
Ribosomes
Plasma membrane
Nucleoid
Cytoplasm
Indicate the bacterial structures that are likely to be antigens, to
which host antibodies bind, marking the invader for phagocytosis
nucleoid
capsule
plasmids
cell wall
ribosomes
fimbriae
flagella
Capsule
Cell wall
Fimbriae
Flagella
(Surface
components are more likely to be "visible" to the host as antigen
Identify antibacterial strategies that would likely be selectively
toxic for bacteria.
1. inhibition of fimbriae
synthesis
2. interfering with lysosomal function
3.
interfering with translation at 70s ribosomes
4. inhibition of
peptidoglycan synthesis
5. inhibition of microtubule function
-inhibition of fimbriae synthesis
- interfering with translation
at 70s ribosomes
- inhibition of peptidoglycan synthesis
A strain of Streptococcus pneumoniae is no longer able to synthesize
its capsular polysaccharide. What is a likely outcome?
It
will be readily phagocytized upon entering the host
It will no
longer be motile
It will no longer be able to carry out
fermentation
It will produce more potent toxins which damage the
host
It will not be able to appropriately transport ions across
its plasma membrane
It will be readily phagocytized upon entering the host
The presence of a polysaccharide capsule is a well-known
virulence factor of Streptococcus pneumoniae. Encapsulated strains
typically produce smooth glistening, mucoid-appearing colonies.
Non-encapsulated strains produce flat, dry colonies. Inoculating mice
with these two strains readily demonstrates the virulence of the
encapsulated strains, and the lack of virulence of the
non-encapsulated strains.
A strain of Neisseria gonorrhoeae has been genetically altered and
can no longer produce fimbriae. What is a likely outcome?
It will
be readily phagocytized upon entering the host
It will
demonstrate increased resistance to antibiotics
It will be unable
to carry out aerobic respiration
It will no longer be able to
secrete exotoxins.
It will be unable to adhere to host tissue and
establish infection
It will be unable to adhere to host tissue and establish infection
Life can arise spontaneously from living matter is an example of what?
Spontaneous generation
Biogenisis
Spontaneous generation
Microorganisms present in nonliving matter can lead to new microorganisms
Spontaneous generation
Biogenisis
Biogenesis
Life can arise as a result of microorganisms present in nonliving matter
Spontaneous generation
Biogenisis
biogenesis
Living cells can arise only from preexisting living cells
Spontaneous generation
Biogenisis
biogensis
Living cells can arise from nonliving matter under favorable conditions
Spontaneous generation
Biogenisis
spontaneous generation
Vital forces in nonliving matter can lead to new life
Spontaneous generation
Biogenisis
spontaneous generation
Louis Pasteur conducted an experiment to disprove the theory of spontaneous generation. What was beef broth used for
Provided a nutritious environment to support microbial growth.
Louis Pasteur conducted an experiment to disprove the theory of spontaneous generation. Bunsen burner (flame)
Provided heat that destroyed microorganisms already present in the beef broth
Louis Pasteur conducted an experiment to disprove the theory of spontaneous generation. Flask with S-shaped neck
Provided the physical conditions for trapping airborne contaminants and preventing microorganisms from entering the flask
Louis Pasteur conducted an experiment to disprove the theory of spontaneous generation. Air.
Provided a source of potential external microbial contaninants
Which of the following conclusions can be drawn from Pasteur’s experiment involving the flasks with S-shaped necks?Select all statements that apply.
*Microbial life can be destroyed by heat.
*Microorganisms can
be present in nonliving matter, such as air, liquids, and solids.
*Pasteur’s observations support the theory of biogenesis.
*Microbes can be blocked from accessing favorable growth environments.
*Beef broth is an unsuitable environment for growing
microorganisms.
*Microbial life can arise from nonliving
matter.
*Pasteur’s observations support the theory of spontaneous generation.
Microbial life can be destroyed by heat. Microorganisms can be present in nonliving matter, such as air, liquids, and solids. Pasteur’s observations support the theory of biogenesis. Microbes can be blocked from accessing favorable growth environments.
Pasteur’s experiments and observations provided the basis for developing aseptic techniques that prevent the introduction of unwanted microorganisms into controlled environments. Given what you have learned from the design of Pasteur’s experiment, which of the following scenarios would be considered an aseptic technique?Select all statements that apply.
*using a Bunsen burner (flame) to heat a wire inoculating loop
prior to use
*blowing on heated, sterile surfaces with your
mouth in order to facilitate cooling
*wearing gloves when
handling sterile laboratory equipment *allowing sterile solutions to
be openly exposed to the air
*taking steps to prevent
contaminants from entering sterile solutions
using a Bunsen burner (flame) to heat a wire inoculating loop prior to use
wearing gloves when handling sterile laboratory equipment
taking steps to prevent contaminants from entering sterile solutions
Name two characteristics of bacteria
Have cell walls that contain peptidoglycan
Derive nutrition from organic or inorganic sources or conduct photosynthesis
Archea (name two characteristics)
Found in extreme environments
Not typically associated with human disease
Fungi (two characteristics)
Can be unicellular or multicellular
Eukaryotic
Viruses (name two characteristics)
Cannot survive outside a host cell
Can be seen only with an electron microscope
One of the first set of experiments to refute spontaneous generation was done in 1688 by Francesco Redi. Which of the following statements regarding Francesco Redi’s experiments is true?
*He determined that material from an infectious agent taken from one person could be used to stimulate immunity in another person.
*His experiments demonstrated that oxygen is essential to all life.
*His experiments determined a series of conditions that must be satisfied in determining the causative agent of disease.
*The results of his experiment demonstrated that living organisms are derived from other living organisms.
The results of his experiment demonstrated that living organisms are derived from other living organisms.
In 1861, Pasteur conducted his now-famous experiments using flasks with long necks bent into an S-shape. Imagine that you are a scientist working in Pasteur’s lab at this time. You decide to tip the flasks so that broth enters the long S-shaped neck. You then return the flask to its upright position. Predict the most likely outcome of tipping one of Pasteur’s S-necked flasks.
*The broth would remain uncontaminated because no microbes could enter the long S-shaped neck of the flask.
*The broth would become contaminated with microbes because they were trapped in the neck.
*Since the broth had been heated (effectively sterilizing it), no microbes would grow in the broth.
*Microbes would grow in the broth because the tipping would introduce the oxygen necessary for microbial growth.
The broth would become contaminated with microbes because they were trapped in the neck.
S. aureus has been isolated from George’s infected wound. To satisfy Koch’s postulates, what would George’s doctor need to do with the isolated S. aureus?
*Inject the S. aureus strain into an animal and see whether it develops the same type of infection that George has.
*Inject the S. aureus into an animal, observe whether the animal gets an infection similar to George’s, and isolate the same strain of S. aureus from the infection.
*Compare the DNA sequence of the strain of S. aureus isolated from George to other S. aureus strains to see whether it has been isolated from other similar infections.
*Inject the S. aureus into an animal; if the animal develops the same infection, isolate the infectious material from the animal and test its ability to vaccinate another animal.
Inject the S. aureus into an animal, observe whether the animal gets an infection similar to George’s, and isolate the same strain of S. aureus from the infection.
Which of the following are limitations of antibiotics?Select all that apply.
*Treatment with antibiotics can lead to the emergence of resistant strains.
*Antibiotics may be toxic.
*Antibiotics are not effective in treating viral infections.
*Mass production of antibiotics is extremely difficult.
*The cost of producing antibiotics is high, which in turn leads to higher prices for consumers.
Treatment with antibiotics can lead to the emergence of resistant strains.
Antibiotics may be toxic.
Antibiotics are not effective in treating viral infections.
Further characterization of the S. aureus isolated from George’s wound reveals that the strain is MRSA. Why is George’s doctor concerned that MRSA has been identified as the causative agent of George’s infection?
*There are no effective antibiotic options for treating MRSA.
*The available treatment options are quite aggressive, including removal of damaged tissue in an effort to contain the infection.
*MRSA is transmissible.
*MRSA is not typically associated with the type of infection that George has.
MRSA is transmissible.
Pick the area of biology that studies DNA and chromosomes. molecular biology
genealogy
genetics
biochemistry
Genetics
Pick step that does NOT follow the postulates.
*A mouse that was exposed to a potential viral pathogen has died and you are able to isolate the virus from the liver of the mouse.
*You give a patient an antibiotic to treat an infection.
*You are able to isolate a pathogenic bacterium from someone with a new type of pharyngitis.
*You collect a throat swab from a family member who has also become sick.
You give a patient an antibiotic to treat an infection.
The current system of nomenclature for organisms was established by:
a.Pasteur.
b.Jenner.
c.Linnaeus.
d.Koch.
Linnaeus .
Scientific nomenclature assigns each organism two names: the genus and the
a.kingdom.
b.specific epithet.
c.family.
d.class.
Specific epithet
Archaea, often found in extreme environments, are divided into
a.two main groups.
b.three main groups.
c.four main groups.
d.five main groups.
Three main groups
In 1978, Carl Woese devised a system ofclassification that groups organisms into the domains Bacteria, Archaea, and
a.Animalia.
b.Eukaryotes.
c.Eukarya.
d.Protozoa.
Eukarya
Eukarya includes ALL of the following EXCEPT
a.viruses.
b.protists.
c.fungi.
d.plants.
Viruses
Robert Koch
a.invented the microscope.
b.discovered penicillin.
c.proved that bacteria can cause disease.
d.observed the first cells.
Proved that bacteria can cause disease
Who discovered a chemotherapeutic agent against syphilis?
a.Jenner
b.Pasteur
c.Koch
d.Ehrlich
Ehrlich
Robert Koch developed his postulates while
identifying the cause of which disease?
a.syphilis
b.anthrax
c.yellow fever
d.tetanus
anthrax
Fleming
a.disproved spontaneous generation.
b.discovered penicillin.
c.discovered phagocytosis.
d.developed the theory of immunity.
Discovered penicillin
Pasteur
a.discovered the cause of fermentation.
b.discovered penicillin.
c.discovered phagocytosis.
d.developed aseptic surgery.
Discovered the cause of fermentation.
Lister is associated with
a.fermentation.
b.vaccination.
c.aseptic surgery.
d.the cell theory.
Aseptic surgery
Jenner is associated with
a.fermentation.
b.vaccination.
c.aseptic surgery.
d.the cell theory.
Vaccination
The process of using just enough heat to kill bacteria that cause spoilage was developed by
a.Pasteur.
b.Ehrlich.
c.Lister.
d.Koch.
Pasteur
Salvarsan was developed by
a.Ehrlich.
b.Fleming.
c.Weizmann.
d.Needham.
Erlich
Cryptosporidiosis, which can be transmitted in a public water supply, is caused by a
a.virus.
b.prion.
c.protozoan.
d.bacterium.
Protozoan
HIV destroys which type of immune cells?
a.neutrophils
b.CD4+ T cells
c.B cells
d.CD8+ T cells
CD4+ T cells
ALL of the following are natural human defenses against disease EXCEPT
a.interferon.
b.penicillin.
c.skin.
d.mucous membranes.
Penicillin
Human disease caused by a prion is known as
a.MRSA.
b.Creutzfeldt-Jakob disease.
c.SARS.
d.West Nile encephalitis.
Cruetzfeldt-Jakob disease
An example of a hemorrhagic fever virus is
a.Marburg virus.
b.human immunodeficiency virus.
c.avian influenza virus.
d.West Nile virus.
Marburg virus
Bacillus thuringiensis is used
a.to treat sewage.
b.in bioremediation.
c.as a natural insecticide.
d.to recycle vital elements.
A natural insecticide
Bioremediation is the use of microbes
a.to clean up pollutants and toxic wastes.
b.in recycling vital elements.
c.to treat sewage.
d.in food production.
To clean up pollutants and toxic wastes
Biotechnology can best be defined as using living organisms to
a.clean up pollution.
b.develop useful products.
c.treat sewage.
d.control pests.
Develop useful products
Gene therapy can be used to treat
a.cystic fibrosis.
b.diphtheria.
c.polio.
d.avian influenza A.
Cystic fibrosis
ONLY bacteria can convert which element into a form that is available to plants and animals?
a.carbon
b.oxygen
c.nitrogen
d.hydrogen
nitrogen
Who challenged the case for spontaneous generation with the concept of biogenesis?
a.Pasteur
b.Virchow
c.Redi
d.Needham
Virchow
What is the function of the diaphragm on a compound microscope?
a.magnifies the specimen
b.focuses light through the specimen
c.holds the microscope slide in position
d.controls the amount of light entering the condenser
controls the amount of light entering the condenser
The ocular lens is used
a.to remagnify the image formed by the objective lens.
b.as the primary lens to magnify the specimen.
c.to increase the light.
d.to decrease the refractive index.
to remagnify the image formed by the objective lens.
The measure of the light-bending ability of a medium is the
a.illumination.
b.magnification.
c.refractive index.
d.resolution.
Refractive index
MOST ocular lenses magnify specimens by a factor of
a.10.
b.100.
c.1000.
d.2000.
10
The ability of the lenses to distinguish fine detail and structure is called
a.illumination.
b.magnification.
c.refractive index.
d.resolution.
Resolution
Which microscope uses an opaque disk to block light that would enter the objective lens directly?
a.fluorescence microscope
b.phase-contrast microscope
c.darkfield microscope
d.confocal microscope
Darkfield microscope
Which microscope uses an ultraviolet light source?
a.fluorescence microscope
b.phase-contrast microscope
c.darkfield microscope
d.confocal microscope
Fluorescence microscope
Which microscope illuminates specimens with blue light and produces three-dimensional images?
a.fluorescence microscope
b.phase-contrast microscope
c.darkfield microscope
d.confocal microscope
Confocal microscope
Which microscope forms an image from two sets of light rays, one from the light source and the other diffracted from a structure in the specimen?
a.fluorescence microscope
b.phase-contrast microscope
c.darkfield microscope
d.confocal microscope
Phase-contrast microscope
What microscope uses a metal and diamond probe to produce a three-dimensional image?
a.atomic force microscope
b.darkfield microscope
c.phase-contrast microscope
d.transmission electron microscope
atomic force microscope
Which microscope is especially useful in studying the surface structures of intact cells and viruses?
a.transmission electron microscope
b.scanning electron microscope
c.phase-contrast microscope
d.darkfield microscope
scanning electron microscope
In transmission electron microscopy, the specimen is placed on a
a.copper mesh grid.
b.glass slide.
c.plastic slide.
d.magnesium mesh grid.
Copper mesh grid
Which microscope is extremely valuable for examining different layers of specimens and often involves the use of shadow casting?
a.transmission electron microscope
b.scanning electron microscope
c.phase-contrast microscope
d.darkfield microscope
Transmission electron microscope
With a scanning electron microscope, objects are generally magnified
a.100 to 100,000x.
b.100 to 10,000x.
c.1000 to 100,000x.
d.1000 to 10,000x.
100 to 10,000X
With a transmission electron microscope, objects are generally magnified
a.1000 to 100,000x.
b.1000 to 10,000x.
c.10,000 to 1,000,000x.
d.10,000 to 100,000x.
10,000 to 1,000,000x
Before microorganisms are stained, MOST appear ________ when viewed with brightfield microscopy.
a.golden
b.green
c.colorless
d.hollow
colorless
The chromophore of basic dyes is a ________ and is ________ to MOST types of bacteria.
a.cation; attracted
b.anion; attracted
c.cation; not attracted
d.anion; not attracted
cation; attracted
Which one of the following is NOT a kind of staining technique?
a.simple
b.differential
c.special
d.selective
Selective
The process of fixing a slide attaches the microorganisms while simultaneously
a.illuminating the organisms.
b.staining the organisms.
c.killing the organisms.
d.magnifying the organisms.
Killing the organisms
In 1978, Carl Woese devised a system of classification that groups organisms into the domains Bacteria, Archaea, and
a.Animalia.
b.Eukaryotes.
c.Eukarya.
d.Protozoa.
Eukarya
What is the mordant in the Gram stain?
a.iodine
b.safranin
c.alcohol-acetone
d.crystal violet
iodine
Flagella are stained with
a.carbolfuchsin.
b.malachite green.
c.methylene blue.
d.crystal violet.
Carbolfuchsin
Capsules are stained using a(n)
a.negative stain.
b.Gram stain.
c.Schaeffer-Fulton stain.
d.acid-fast stain.
negative stain
Endospores are stained using a(n)
a.negative stain.
b.Gram stain.
c.Schaeffer-Fulton stain.
d.acid-fast stain.
Schaeffer-Fulton stain
What color are gram-negative bacteria at the completion of the Gram staining process?
a.pink
b.purple
c.colorless
d.brown
Pink
The appearance of Mycobacterium leprae after they are stained with an acid-fast stain is
a.purple.
b.red.
c.colorless.
d.brown.
Red
Bacteria that divide in multiple planes and form grapelike clusters are called
a.streptococci.
b.staphylococci.
c.coccobacilli.
d.vibrios.
Stphylococci
Bacteria divide by
a.binary fission.
b.spore formation.
c.mitosis.
d.budding.
Binary fission
Which of the following statements is TRUE for prokaryotes?
a.They generally lack organelles.
b.Their DNA is associated with histones.
c.Their cell walls are chemically simple.
d.Their DNA is enclosed in an internal membrane.
They generally lack organelles
How long are MOST bacteria?
a.0.2 to 2.0 µm
b.1.0 to 4.0 µm
c.2.0 to 8.0 µm
d.5.0 to 15.0 µm
2.0 to 8.0 µm
The word Bacillus may refer to
a.rod-shaped cells.
b.spherical cells.
c.a specific genus.
d.rod-shaped cells and a specific genus.
Rod-shaped cells and a specific genus
Some bacteria stain gram-positive and others stain gram-negative because of differences in the structure of their
a.cell wall.
b.capsule.
c.cell membrane.
d.endospore.
Cell wall
The bacterial cell wall is composed of
a.cellulose.
b.glucan.
c.chitin.
d.peptidoglycan.
Peptidoglycan
The cell walls of gram-positive bacteria contain
a.mannan.
b.teichoic acid.
c.cellulose.
d.chitin.
Teichoic acid
The outer membrane of gram-negative bacteria contains
a.sterols.
b.mycolic acid.
c.teichoic acid.
d.lipopolysaccharide.
lipopolysaccharide
Acid-fast cell walls contain high concentrations of
a.teichoic acid.
b.peptidoglycan.
c.pseudomurein.
d.mycolic acid.
Mycolic acid
A bacterium possessing a tuft of flagella at one end of its cell is called
a.amphitrichous.
b.lophotrichous.
c.monotrichous.
d.peritrichous.
Lophotrichous
What structure protects pathogenic bacteria from phagocytosis?
a.capsule
b.endospore
c.flagellum
d.axial filament
Capsule
Spirochetes move by means of
a.axial filaments.
b.flagella.
c.pili.
d.fimbriae.
Axial filaments
Which of the following is NOT a part of a flagellum?
a.filament
b.hook
c.fimbriae
d.basal body
fimbriae
Proteins that distinguish among serovars of gram-negative bacteria are found in which structures?
a.fimbriae
b.pili
c.flagella
d.axial filaments
Flagella
Molecules of extrachromosomal DNA in bacteria are known as
a.Golgi complexes.
b.lysosomes.
c.plasmids.
d.ribosomes.
Plasmids
Inclusions of iron oxide in bacteria are found in structures known as
a.gas vacuoles.
b.magnetosomes.
c.endospores.
d.metachromatic granules.
Magnetosomes
Which of the following structures allows a cell to survive adverse environmental conditions?
a.capsule
b.carboxysome
c.endospore
d.gas vacuole
Endospores
Bacteria that divide in multiple planes and form grapelike clusters are called
a.streptococci.
b.staphylococci.
c.coccobacilli.
d.vibrios.
staphylococci
Prokaryotic ribosomes are composed of two subunits of what sizes?
a.20S + 50S
b.30S + 40S
c.30S + 50S
d.40S + 60S
30S + 50S
Which of the following contain 70S ribosomes?
a.prokaryotes
b.mitochondria
c.mitochondria and chloroplasts
d.prokaryotes, mitochondria, and
chloroplasts
Prokaryotes, mitochondria, and chloroplasts
True or false: Most microorganisms are colorless unless they are photosynthetic
True
The building of complex organic molecules from simpler ones is called
a.catabolism.
b.anabolism.
c.photosynthesis.
d.oxidation.
Anabolism
Toxic hydrogen peroxide in some bacteria can be broken down into water and oxygen by the enzyme
a.superoxide dismutase.
b.peroxidase.
c.hydroxylase.
d.catalase.
Catalase
Inhibitors that fill the enzyme's active site and compete with the normal substrate are
a.noncompetitive.
b.allosteric.
c.competitive.
d.ribosomal.
Competitive
Enzymes increase the speed of a chemical
reaction by
a.lowering the energy of activation.
b.increasing the energy of activation.
c.changing the pH of the reaction.
d.increasing the temperature of the reaction.
Lowering the energy of activation.
Many apoenzymes are inactive by themselves and must be activated by
a.cofactors and/or coenzymes.
b.ATP.
c.holoenzymes.
d.substrates.
Cofactors and/or coenzymes
The addition of phosphate to a chemical compound is called
a.glycolysis.
b.oxidation.
c.reduction.
d.phosphorylation.
Phosphorylation
What process does the aerobic electron transport chain perform?
a.glycolysis
b.oxidative phosphorylation
c.photophosphorylation
d.substrate-level phosphorylation
Oxidative phosphrylation
A molecule that undergoes reduction
a.becomes phosphorylated.
b.loses a hydrogen atom.
c.gains one or more electrons.
d.loses one or more electrons.
Gains one or more electrons
The energy from catabolic reactions is used to produce
a.ADP.
b.ATP.
c.AMP.
d.phosphate.
ATP
In which of the following is light energy converted to ATP, which is then used to synthesize organic molecules?
a.photosynthesis
b.Krebs cycle
c.fermentation
d.glycolysis
Photosynthesis
In prokaryotes, how many ATP molecules are produced from the breakdown of one glucose via aerobic respiration?
a.2
b.4
c.34
d.38
38
The pentose phosphate pathway provides a means to break down glucose and
a.five-carbon sugars.
b.proteins.
c.lipids.
d.ATP.
Five-carbon sugars
________ use electrons from reduced inorganic compounds as a source of energy and CO2 as a source of carbon.
a.Photoautotrophs
b.Photoheterotrophs
c.Chemoautotrophs
d.Chemoheterotrophs
Chemoautotrophs
In lipid biosynthesis, glycerol is derived from dihydroxyacetone phosphate formed during
a.the Krebs cycle.
b.glycolysis.
c.the electron transport chain.
d.the Calvin-Benson cycle.
Glycolysis
If an amine group added to a precursor comes from a preexisting amino acid, the process is called
a.beta-oxidation.
b.amination.
c.transamination.
d.beta-reduction.
Transamination
Metabolic pathways that function in BOTH
anabolism and catabolism are called ________
pathways.
a.intermediate
b.reversible
c.redox
d.amphibolic
Amiphibolic
In fermentation,
a.the final electron acceptor is organic.
b.a large amount of ATP is produced.
c.oxygen is required.
d.an electron transport chain is required.
The final electron acceptor is organic
The optimum pH for MOST bacteria is near
a.1.
b.5.
c.7.
d.9.
7
A psychrophile has an optimal growth temperature of about
a.15°C.
b.25°C.
c.37°C.
d.100°C.
15 C
Organisms that require high salt concentrations for growth are called
a.thermophiles.
b.obligate halophiles.
c.acidophiles.
d.anaerobes.
Obligate halphophiles
What is/are the energy source(s) utilized by primary producers in the hydrothermal vents on the ocean floor?
a.light
b.hydrogen sulfide
c.organic molecules
d.carbon dioxide
Hydrogen sulfide
Addition of salts preserves foods because they
a.lower pH.
b.increase osmotic pressure.
c.create an isotonic environment.
d.lower osmotic pressure.
Increase osmotic pressure
Chemoautotrophs and photoautotrophs derive their carbon from
a.carbon dioxide.
b.proteins.
c.lipids.
d.carbohydrates.
Carbon dioxide
Some microorganisms use gaseous nitrogen directly from the atmosphere in a process called
a.denitrification.
b.photosynthesis.
c.nitrogen fixation.
d.nitrogen synthesis.
Nitrogen fixation
An organism that uses oxygen when present but can grow without oxygen is called a(n)
a.obligate aerobe.
b.facultative anaerobe.
c.microaerophile.
d.aerotolerant anaerobe.
Facultative anaerobe
Which organism is killed by atmospheric oxygen?
a.facultative anaerobe
b.obligate aerobe
c.obligate anaerobe
d.aerotolerant anaerobe
Obligate aerobe
Toxic hydrogen peroxide in some bacteria can be broken down into water and oxygen by the enzyme
a.superoxide dismutase.
b.peroxidase.
c.hydroxylase.
d.catalase.
Catalase
Generation time can best be defined as
a.the length of time it takes for lag phase.
b.the duration of log phase.
c.the time it takes for a cell to divide.
d.how many generations a cell can divide.
the time it takes for a cell to divide.
Bacterial growth is usually graphed using ________ scales.
a.arithmetic
b.exponential
c.logarithmic (semi-logarithmic)
d.inverse
logarithmic (semi-logarithmic)
In which growth phase is there intense activity preparing for population growth, but no increase in population?
a.stationary phase
b.log phase
c.death phase
d.lag phase
Lag phase
Which of the following is NOT a possible reason why exponential growth stops?
a.accumulation of waste products
b.exhaustion of nutrients
c.harmful changes in pH
d.bacteria becoming dormant
bacteria becoming dormant
In the stationary phase,
a.the number of microbial deaths exceeds the number of new cells formed.
b.the number of microbial deaths is equal to the number of new cells formed.
c.new cells are no longer formed because of adverse environmental conditions.
d.cellular reproduction is most active.
the number of microbial deaths is equal to the number of new cells formed.
Which type of medium suppresses the growth of unwanted bacteria and encourages growth of desired microbes?
a.differential media
b.complex media
c.selective media
d.enrichment media
Selective media
Microbes that are introduced into a culture medium to initiate growth are called a(n)
a.inoculum.
b.culture.
c.specimen.
d.medium.
Inoculum
What is added to a medium when it is desirable to grow bacteria on a solid medium?
a.glucose
b.magnesium sulfate
c.sodium thioglycollate
d.agar
agar
A culture medium made of extracts from yeasts, meat, or plants is a ________ medium.
a.complex
b.selective
c.differential
d.chemically defined
Complex
Labs intended for highly infectious airborne pathogens, such as tuberculosis, are classified as
a.BSL-1.
b.BSL-2.
c.BSL-3.
d.BSL-4.
BSL-3
A spectrophotometer can be used to measure
a.metabolic activity.
b.turbidity.
c.dry weight.
d.pathogenicity.
Turbidity
The method in which a measured volume of bacterial suspension is placed within a defined area on a microscope slide is called the
a.direct microscope count.
b.pour plate method.
c.spread plate method.
most probable number method.
Direct microscope count
Which process is used to ensure that plates contain 30 to 300 colonies when counted?
a.turbidity
b.serial dilution
c.filtration
d.pour plates
Serial dilution
Which is the best technique to use to measure the growth of filamentous organisms?
a.most probable number method
b.direct microscopic count
c.turbidity
d.dry weight
Dry weight
Which method is a statistical estimating technique used to determine the number of bacteria in a sample?
a.turbidity
b.spread plate method
c.most probable number method
d.pour plate method
Most probable number method
Starting with one bacterial cell, how many cells would you have after 10 generations?
a.10
b.20
c.200
d.1024
1024
Each of the following organisms would be considered a microbe EXCEPT:
a) yeast
b) protozoan
c) bacterium
d) Cat
e) virus
Cat
Yeast and protozoan are both eukaryotic
The arguments supporting spontaneous generation were finally
disproved by:
a) Louis Pasteur
b) Francesco Redi
c)
Rudolf Virchow
d) John Needham
e) Lazzaro Spallanzani
A) Louis Pasteur
The term used to describe a disease-causing microorganism:
a)
microbe
b) bacterium
c) virus
d) pathogen
e) infection
Pathogen: small # of microorganisms
Which physician is first associated with vaccination?
a)
Ehrlich
b) Jenner
c) Lister
d) Koch
e) Escherich
Jenner
In the name Staphylococcus aureus, aureus is the
a)
genus
b) domain name
c) species
d) kingdom
e)
family name
species
Which disease has been eliminated through the use of
vaccines:
a) tuberculosis
b) measles
c) rubella
d)
smallpox
e) infuenza
smallpox
Viruses are not considered living organisms because they
a)
cannot reproduce by themselves
b) are structurally very
simple
c) can only be visualized using an electron
microscope.
d) are typically associated with disease
e) are
ubiquitous in nature
a) cannot reproduce by themselves
If a microscope has an objective lens labeled 63X and an ocular lens of 10x what is the final magnification of this scope?
63X10=630