Exam 1 Flashcards
Which of the following is true of the microbial world?
A. All microbes are harmful.
B. Humans could survive without microbes.
C. Many microbes are helpful.
D. Most microbes are pathogenic.
C. Many microbes are helpful
Which of the following is when humans first suspected the existence of microbes?
A. during the Industrial Revolution
B. in prehistoric times
C. in the last century
D. within the last 500 years
B. in prehistoric times
Which individual first observed unicellular organisms, which he called “animalcules,” using
a microscope he developed?
A. Robert Koch
B. Louis Pasteur
C. Thucydides
D. Antonie van Leeuwenhoek
D. Antonie van Leeuwenhoek
To reduce the risk of open flame from Bunsen burners, microbiologists are increasingly using
which of the following devices for easy, rapid benchtop sterilization of small pieces of
equipment?
A. autoclaves
B. ethylene oxide
C. incubators
D. microincinerators
D. microincinerators
The Swedish botanist known for having developed an important biological classification
system is which of the following people?
A. Ernst Haeckel
B. Carolus Linnaeus
C. Louis Pasteur
D. Robert Whittaker
B. Carolus Linnaeus
Which kingdom was the only one found in Empire Prokaryota?
A. Animalia
B. Fungi
C. Monera
D. Protista
C. Monera
Which are the three currently accepted domains?
A. Archaea, Bacteria, and Eukarya
B. Archaea, Prokaryota, and Eukaryota
C. Bacteria, Fungi, and Protista
D. Bacteria, Prokaryota, and Eukarya
A. Archaea, Bacteria, and Eukarya
Which two taxonomic units are typically used to identify an organism when using binomial
nomenclature?
A. domain and kingdom
B. genus and family
C. genus and species
D. phylum and class
C. genus and species
Which of the following is not true about the process of fermentation?
A. It can help preserve foods, preventing spoilage.
B. It converts sugars to organic acids, alcohols, and/or gases such as carbon dioxide.
C. It is carried out exclusively by unicellular eukaryotes such as yeast.
D. It is used to make foods such as cheese and bread.
C. It is carried out exclusively by unicellular eukaryotes such as yeast.
The Romans may have reduced their risk of waterborne infectious diseases by using which of
the following?
A. a variety of pharmaceutical products
B. aqueducts and a sewer system
C. prophylactic antibiotics
D. quarantine of people with leprosy
B. aqueducts and a sewer system
For which of the following is Thucydides known?
A. developing an effective sewer system in ancient Greece, helping to reduce levels of
disease in cities
B. observing microbes, using a microscope, for the first time, even distinguishing between
bacteria and fungi
C. proposing that disease was caused by microorganisms
D. realizing that people who had been infected by the Athenian plague had immunity to
reinfection
D. realizing that people who had been infected by the Athenian plague had immunity to
reinfection
Ernst Haeckel proposed a classification system consisting of which of the following
subgroups?
A. five kingdoms
B. four kingdoms
C. two domains and three kingdoms
D. two domains and five kingdoms
B. four kingdoms
Viruses not included in phylogenetic trees for which of the following reasons?
A. It is too difficult to observe their characteristics.
B. They are acellular and nonliving.
C. They do not have any genes, which prevents genetic analysis.
D. They lack a nucleus.
B. They are acellular and nonliving.
Which is the best description of the primary purpose of a phylogeny?
A. Phylogenies show all the alterative names for each species.
B. Phylogenies show all the common names for each species.
C. Phylogenies show evolutionary relatedness between organisms.
D. Phylogenies show interactions between species in a shared habitat.
C. Phylogenies show evolutionary relatedness between organisms.
Current phylogenetic analyses include which of the following?
A. information from a range of sources, including morphological, genetic, and biochemical
data
B. information on visible similarities only
C. information regarding how to classify organisms on the basis of external morphological
characteristics and visible behaviors
D. varied morphological and structural characteristics, with preference for leaving historical
classifications to prevent confusion
A. information from a range of sources, including morphological, genetic, and biochemical
data
. Diatoms are classified within which of the following domains?
A. Archaea
B. Bacteria
C. Eukarya
D. Prokaryota
C. Eukarya
Horizontal gene transfer involves which of the following?
A. any transfer of genes in a laboratory setting
B. the transfer of genes from a virus to a bacterium or vice versa but not any other form of
gene transfer
C. the transfer of genes from one individual to another, including from one species to
another, but not from parent to offspring
D. the transfer of genes from parent to offspring
C. the transfer of genes from one individual to another, including from one species to
another, but not from parent to offspring
Bacteria are generally identified to species by using which of the following?
A. a combination of genetic, biochemical, and microscopic approaches
B. a combination of microscopic and physiological approaches, but not genetics
C. primarily characteristics such as motility that can be visualized using microscopy
D. primarily morphological characteristics of individual cells
A. a combination of genetic, biochemical, and microscopic approaches
For taxonomic classification of microbes, serological tests typically are used to do which of
the following?
A. determine complete genome sequences for microbes
B. identify proteins on the basis of their reaction with specific antibodies
C. run analyses to identify whether particular genes are present
D. visualize microbial external morphology
B. identify proteins on the basis of their reaction with specific antibodies
Which of the following is true of bacterial strains?
A. They are closely related subtypes within a bacterial species that may or may not have similar properties.
B. They are informal bacterial groupings used for medical distinctions but not recognized for
classification purposes.
C. They are more distantly related to each other than are members of a single bacterial
species.
D. They are very similar bacteria with almost identical properties
A. They are closely related subtypes within a bacterial species that may or may not have similar properties.
Bergey’s Manual of Systematic Bacteriology is used primarily as which of the following?
A. a guide to bacterial shapes
B. a historical account of changes in classification techniques
C. a list and characterization of all known medically relevant microbes
D. a reference for bacterial classification
D. a reference for bacterial classification
Which of the following indicates how bacteria and viruses typically compare in size?
A. Bacteria are indistinguishable from viruses.
B. Bacteria are much larger than viruses.
C. Bacteria are much smaller than viruses.
D. Bacteria are similar in size to viruses.
B. Bacteria are much larger than viruses.
- Viruses are classified as which of the following?
A. Archaea
B. Bacteria
C. Eukarya
D. distinct from the three-domain system
D. distinct from the three-domain system
Which of the following is not a curved bacterial shape?
A. bacillus
B. spirillum
C. spirochete
D. vibrio
A. bacillus
Based just on the name, which of the following groups of bacteria contains entirely species
that consume organic compounds for food?
A. cyanobacteria
B. green nonsulfur bacteria
C. green sulfur bacteria
D. nonphotosynthetic bacteria
D. nonphotosynthetic bacteria
Chitin cell walls are characteristic of which taxonomic group?
A. algae
B. archaea
C. bacteria
D. fungi
D. fungi
Yeasts are which of the following?
A. a type of algae
B. a type of protist
C. any unicellular microbe
D. unicellular fungi
D. unicellular fungi
The cell walls of archaeans often contain which of the following substances?
A. cellulose
B. chitin
C. peptidoglycan
D. pseudopeptidoglycan
D. pseudopeptidoglycan
Which of the following is not true of archaeans?
A. Some species live on the human body.
B. They are genetically distinct from bacteria.
C. They are only found in extreme environments.
D. They have substantial metabolic differences from bacteria.
C. They are only found in extreme environments.
Which of the following is not true of algae?
A. All the algae are classified together in one similar group closely related to green plants.
B. Ingredients made from algae, including carrageenan, are used in food products.
C. They are being used to develop biofuels.
D. They are sometimes multicellular.
A. All the algae are classified together in one similar group closely related to green plants.
Oral thrush is caused by which type of organism?
A. algae
B. bacteria
C. fungi
D. protists
C. fungi
Mycotoxins are produced by which type of organism?
A. archaeans
B. heterotrophic protists
C. molds
D. protozoans
C. molds
Which of the following is not a common use of fungi?
A. the production of alcoholic beverages
B. the production of carrageenan
C. the production of cyclosporine
D. the production of penicillin
B. the production of carrageenan
The guinea worm is best described as which of the following?
A. a helminthic parasite transmitted by consuming contaminated water
B. a type of mold that grows into a worm-like shape and produces antimicrobial chemicals
C. a type of protist found in water that has not been properly treated
D. a type of protozoan that is unusual because it is multicellular
A. a helminthic parasite transmitted by consuming contaminated water
Which of the following is true of the genetics of viruses?
A. Viruses always contain DNA and force host cells to produce RNA.
B. Viruses always contain DNA and RNA.
C. Viruses always contain RNA and force host cells to produce DNA.
D. Viruses can contain either DNA or RNA, but not both.
D. Viruses can contain either DNA or RNA, but not both.
Which term is used to refer to a wave’s rate of vibration?
A. amplitude
B. frequency
C. trough
D. wavelength
B. frequency
On the electromagnetic spectrum, which type of wave has the shortest wavelength?
A. cosmic ray
B. infrared ray
C. ultraviolet ray
D. visible light
A. cosmic ray
Dyes are often used during microscopy to increase which of the following?
A. contrast
B. magnification
C. motility
D. resolution
A. contrast
Which of the following was the first to use the term “cells”?
A. Robert Hooke
B. Robert Koch
C. Carolus Linnaeus
D. Antonie van Leeuwenhoek
A. Robert Hooke
Which of the following is the typical magnification of an object viewed using a 10× ocular
lens and a 100× objective lens on a brightfield microscope?
A. 1×
B. 10×
C. 100×
D. 1000×
D. 1000×
Most modern microscopes have two eyepieces, meaning that they are which of the
following?
A. binocular
B. monocular
C. oil immersion
D. trinocular
A. binocular
An annular stop is used for which type of microscopy?
A. confocal
B. darkfield
C. fluorescence
D. phase contrast
D. phase contrast
Which of the following is the specific name for a stain that colors the background but not the specimen?
A. acid-fast stain
B. counterstain
C. differential stain
D. negative stain
D. negative stain
Which type of microscopy would work best for viewing internal cell structures?
A. atomic force microscopy
B. scanning electron microscopy
C. scanning tunneling microscopy
D. transmission electron microscopy
D. transmission electron microscopy
The Gram-staining procedure is best described as which of the following?
A. complex staining
B. differential staining
C. negative staining
D. simple staining
B. differential staining
When there is a substantial difference in refractive index between two materials, which of the
following describes what will happen to light passing from one material to the other?
A. It will fail to be refracted.
B. It will undergo a large amount of refraction.
C. It will undergo a small amount of refraction.
D. It will undergo a variable amount of refraction.
B. It will undergo a large amount of refraction.
. In microscopy, the focal length refers to which of the following?
A. a description of the wavelength needed for an image to be in focus
B. a measure of the amount of refraction produced by a lens
C. a measure of the thickness of the lens needed for an image to be in focus
D. the distance to the image point (at which all light entering a lens is parallel)
D. the distance to the image point (at which all light entering a lens is parallel)
Which of the following are pigments used in microscopy to absorb and reflect light?
A. chromatographs
B. chromophores
C. oilophores
D. photophores
B. chromophores
Negative staining is the standard approach used to visualize which structure(s)?
A. capsules
B. endospores
C. flagella
D. nucleoid regions
A. capsules
Which is a standard mordant used in flagella staining?
A. basic fuchsin
B. iodine
C. safranin
D. tannic acid
D. tannic acid
Which of the following pairs are common acid-fast staining techniques?
A. Gram and Kinyoun
B. negative and Schaeffer-Fulton
C. Ziehl-Neelsen and Kinyoun
D. Ziehl-Neelsen and Schaeffer-Fulton
C. Ziehl-Neelsen and Kinyoun
Which is the primary stain used in the Ziehl-Neelsen technique?
A. acid-alcohol
B. carbolfuchsin
C. crystal violet
D. methylene blue
B. carbolfuchsin*
. Which is the correct order of steps in Gram staining?
A. crystal violet stain, ethanol decolorization, Gram’s iodine mordant, safranin counterstain
B. crystal violet stain, Gram’s iodine mordant, ethanol decolorization, safranin counterstain
C. ethanol stain, crystal violet rinse, safranin counterstain, Gram’s iodine mordant
D. safranin stain, Gram’s iodine mordant, ethanol decolorization, crystal violet counterstain
B. crystal violet stain, Gram’s iodine mordant, ethanol decolorization, safranin counterstain
It is important to fix bacterial smears on a slide for which of the following reasons?
A. to attach them to the slide
B. to cause swelling of the cell to make interior structures more visible
C. to enhance the uptake of stains
D. to provide a nutrient medium to sustain the bacteria
A. to attach them to the slide
Which of the following is not commonly used for chemical fixation?
A. acetic acid
B. ethanol
C. glutaraldehyde
D. iodine
D. iodine
Which of the following is not involved in preparing a bacterial slide for Gram staining?
A. allowing the sample to dry on the slide
B. fixing the specimen to the slide
C. placing a smear on the slide
D. preparing a wet mount
D. preparing a wet mount
Which of the following most specifically refers to stains with positively charged
chromophores?
A. acid-fast dyes
B. acidic dyes
C. basic dyes
D. positive dyes
C. basic dyes
. Which of the following most specifically refers to a stain that dyes a specimen rather than the
background?
A. counterstain
B. mordant
C. negative stain
D. positive stain
D. positive stain
Which of the following describes the difference between the Ziehl-Neelsen and Kinyoun
acid-fast staining techniques?
A. The Ziehl-Neelsen technique uses a counterstain and the Kinyoun technique does not.
B. The Ziehl-Neelsen technique uses an acidic dye and the Kinyoun technique does not.
C. The Ziehl-Neelsen technique uses heat and the Kinyoun technique does not.
D. The Ziehl-Neelsen technique uses two dyes and the Kinyoun technique does not.
C. The Ziehl-Neelsen technique uses heat and the Kinyoun technique does not.
Which of the following described the difference between gram-positive and gram-negative
cells that causes them to stain differently after Gram staining?
A. Gram-positive cells have a mycolic acid layer in their cell walls that holds in stain,
whereas gram-negative cells lack this layer.
B. Gram-positive cells have capsules and gram-negative cells have S layers.
C. Gram-positive cells have thicker cell membranes than gram-negative cells.
D. Gram-positive cells have thicker peptidoglycan layers in their cell walls than do gramnegative cells.
D. Gram-positive cells have thicker peptidoglycan layers in their cell walls than do gramnegative cells.
Which of the following would not potentially cause a gram-positive cell to appear gramnegative after Gram staining?
A. counterstaining with crystal violet instead of safranin
B. exposing the cells to ethanol for too long
C. using older bacterial cultures
D. using safranin as a primary stain
A. counterstaining with crystal violet instead of safranin
Which of the following does not cause the probe to move up and down above the specimen
in atomic force microscopy?
A. chemical bonding
B. electrostatic forces
C. van der Waals forces
D. variations in current
D. variations in current
Quantum tunneling of electrons is important in the mechanism underlying which microscope
type?
A. AFM
B. SEM
C. STM
D. TEM
C. STM
Which of the following is the chemical in some bacterial cells’ walls that makes them resist
decolorization after acid-fast staining?
A. acetic acid
B. mycolic acid
C. peptidoglycan
D. phospholipid
B. mycolic acid
Gram staining is useful for bacterial identification. Which of the following is another way it
is most useful?
A. Knowing Gram staining results allows a researcher to know which organisms a bacterium
can infect.
B. Knowing Gram staining results allows a researcher to select the appropriate growth
medium for optimal bacterial growth.
C. Knowing Gram staining results is helpful in choosing an effective antibiotic.
D. Knowing Gram staining results is helpful in understanding a bacterium’s metabolic
C. Knowing Gram staining results is helpful in choosing an effective antibiotic.
Which of the following is not true regarding capsule staining?
A. Capsules are typically stained using basic dyes.
B. Capsule staining does not require heat fixation in advance.
C. Capsule staining requires careful selection of a stain that can stain the capsule itself.
D. Capsule staining typically involves negative staining.
A. Capsules are typically stained using basic dyes.
Because endospores are difficult to stain, which of the following is generally needed?
A. Heat must be used to make the endospore take up stain.
B. Mycolic acid must be added to encourage the endospore to take up stain.
C. Negative staining must be used to stain endospores because they do not absorb stain.
D. The cells must be cooled to make the endospore more brittle prior to staining.
C. Negative staining must be used to stain endospores because they do not absorb stain.
When endospores are stained using the Schaeffer-Fulton method, which of the following
correctly describes how they appear after staining?
A. The endospore appears green within a pink cell, because only the endospore retained the
primary stain.
B. The entire cell appears green because the endospore surrounds all the vegetative material.
B. The entire cell appears pink because the endospore surrounds all the vegetative material.
C. The entire cell appears pink except for a clear area representing the endospore.
A. The endospore appears green within a pink cell, because only the endospore retained the
primary stain.
Specimens for TEM are prepared by doing which of the following?
A. dehydrating the specimen in ethanol and then coating it in a material that will repel
electrons
B. sputter coating with a substance such as gold to repel electrons
C. using an ultramicrotome to cut very thin sections from samples embedded in plastic resin
D. using chemical fixation, followed by standard staining techniques such as the Gram stain
C. using an ultramicrotome to cut very thin sections from samples embedded in plastic resin*
The idea that life could appear from nonliving materials was called which of the following?
A. the cell theory
B. the cellular genesis theory
C. the theory of biogenesis
D. the theory of spontaneous generation
D. the theory of spontaneous generation
The first known use of epidemiology to trace the source of a disease outbreak was the
identification of contaminated water as the cause of cholera transmission in London. Which
of the following was the physician who accomplished this?
A. Joseph Lister
B. John Needham
C. Ignaz Semmelweis
D. John Snow
D. John Snow
Which of the following is a series of steps for determining the causative agent of a particular
disease?
A. Koch’s postulates
B. Lister’s checklists
C. Pasteur’s principles
D. Semmelweis’ guidelines
A. Koch’s postulates
Which scientist performed an elegant series of experiments that finally and definitively
disproved the theory of spontaneous generation?
A. John Needham
B. Louis Pasteur
C. Francesco Redi
D. Jan Baptista van Helmont
B. Louis Pasteur
Prokaryotes are classified into which domain(s)?
A. Domain Archaea only
B. Domain Bacteria only
C. Domains Archaea and Bacteria only
D. Domains Bacteria and Eukarya only
C. Domains Archaea and Bacteria only
Which term refers to a curved rod?
A. bacillus
B. coccus
C. spirillum
D. vibrio
D. vibrio
When a bacterial cell with a cell wall is placed in salt water with a higher-solute
concentration than the cell cytoplasm, the cell will undergo which of the following?
A. crenation
B. crenolysis
C. lysis
D. plasmolysis
D. plasmolysis
The bacterial chromosome located in which of the following?
A. the capsule
B. the nucleoid region
C. the nucleus
D. the thylakoids
B. the nucleoid region
Which scientist thought spontaneous generation had occurred in flasks of broth after the
broth had been boiled?
A. John Needham
B. Louis Pasteur
C. Francesco Redi
D. Jan Baptista van Helmont
A. John Needham
Which of the following is not evidence for the endosymbiotic theory?
A. Chloroplasts and mitochondria contain ribosomes that resemble prokaryotic ribosomes.
B. Chloroplasts and mitochondria contain their own DNA that resembles prokaryotic DNA.
C. Chloroplasts and mitochondria have structures that resemble prokaryotic cell walls.
D. Chloroplasts and mitochondria reproduce using binary fission, like prokaryotic cells.
C. Chloroplasts and mitochondria have structures that resemble prokaryotic cell walls.