Microbiology Final Exam
When pairs of electrons are shared between two atoms, the result is
a/an _______ bond.
a) are responsible for converting sunlight to chemical energy
b) are present only in photosynthetic organisms
c) have a double membrane
d) are responsible for protein synthesis
have a double membrane
Which of the following statements is false?
a) All bacteria are capable of forming capsules.
b) The chemical composition of each capsule is unique to a particular strain of bacteria.
c) Slime layers are usually thinner than capsules.
d) A slime layer protects bacteria against drying and helps trap nutrients near a cell.
All bacteria are capable of forming capsules.
Koch's postulates were:
a) specific to anthrax and tuberculosis but don't apply to other diseases
b) designed to establish a casual relationship between a causative microbe and a disease c) strict in that microorganisms isolated from experimentally inoculated hosts had to be different from the microorganism that was introduced into the host.
d) interpreted as many organism could cause the same disease
designed to establish a casual relationship between a causative microbe and a disease
Light of ________ wavelength typically will result in ________
a) longer, better
b) shorter, better
c) any, poor
d) shorter, worse
Which is the correct ordering of cell wall components starting from
outside the cell and going inward?
a) In gram positive bacteria: peptidoglycan, cell membrane
b) In gram negative bacteria: peptidoglycan, lipopolysaccharide, periplasmic space, outer membrane, cell membrane
c) In acid fast bacteria: peptidoglycan, lipid layer, cell membrane
d) In gram negative bacteria: peptidoglycan, periplasmic space, lipid membrane
In gram positive bacteria: peptidoglycan, cell membrane
Which of the following is not a common bacterial shape?
The lens closest to the slide during a microscopic examination is the
The most important structural component of bacterial cell walls is
a) teichoic acid
b) lipotechoic acid
d) glutamic acid
In bacteria, the cell membrane functions in the all of the following
a) regulate movement of materials into and out of the cell
b) synthesizes cell wall components
c) serve as the site for protein synthesis
d) assists with DNA replication
serve as the site for protein synthesis
An ion is all of the following except:
a) a charged atom
b) an atom that has lost or gained one or more electrons
c) either a cation or an anion
d) an atom with the same number of protons as electrons
an atom with the same number of protons as electrons
Why do basic dyes attach to most bacterial surfaces?
a) Most bacterial surfaces are negatively charged.
b) Bacterial cells take up safranin.
c) Most bacterial surfaces resist taking up the stain.
d) Most bacterial surfaces do not have a charge.
Most bacterial surfaces are negatively charged.
Peptidoglycan makes up more than 50% of a ________ cell wall.
a) Gram negative
b) Gram positive
c) Gram variable
a) have a charged phosphate group that can mix with water and insoluble fatty acids.
b) can serve as hormones.
c) always remain liquid at room temperature.
d) form straight chains in water.
have a charged phosphate group that can mix with water and insoluble fatty acids.
A parasitologist studies parasites. What does a mycologist
b) how viruses cause disease and are involved in cancer
c) the development of chemical substances to treat diseases
The Fluid-mosaic model describes the structure of _____.
a) cell walls
b) cell membranes
d) endosymbiotic relationships
What discovery was crucial to the founding of the field of
a) Isolation of lepers limiting the spread of infectious disease
b) Agglutination of bacteria in immune serum
c) The chemical composition of DNA, the genetic material
d) Microscopes which allowed for the direct observation of microbes
Microscopes which allowed for the direct observation of microbes
A small comma shaped bacteria is described as being a
The English scientist Robert Hooke coined the term cell because the
small boxes he saw in the microscope reminded him of a monk's room.
What is the cell theory that was later proposed?
a) Cells are fundamental units of life.
b) Replication requires the division of cells into two equal cells.
c) Hereditary information is passed on in the form of DNA.
d) All organisms are unicellular, made up of one cell.
Cells are fundamental units of life.
The first person to use a microscope to observe cells invisible to
the naked eye was:
a) Robert Hooke
b) Matthias Schleiden
c) Anton van Leeuwenhoek
d) Louis Pasteur
Anton van Leeuwenhoek
Osmosis most directly involves:
a) water moving down a concentration gradient
b) organic molecules crossing a membrane
c) energy being expended to import large molecules into the cell
d) sugars and salts moving down their concentration gradient
water moving down a concentration gradient
Which of the following is not found in bacterial cells?
a) A cell membrane, usually surrounded by a cell wall
b) An internal cytoplasm with ribosomes, a nuclear region and in some cases granules c) A variety of external structures, such as capsules, flagella and pili
d) Respiratory enzymes contained in an internal structure surrounded by membranes
Respiratory enzymes contained in an internal structure surrounded by membranes
A simple stain:
a) uses only a single dye.
b) requires only one step to stain a slide.
c) distinguishes between two different parts of an organism. d) is composed of an equal balance of acid and basic dyes.
uses only a single dye.
Electron microscopes have a much better resolving power when compared
to light microscopes because electrons _____.
a) are invisible to the eye
b) have longer wavelengths than visible light rays
c) have shorter wavelengths than visible light rays
d) are negatively charged
have shorter wavelengths than visible light rays
Microbes live in us, on us and nearly everywhere around us. Which of
the following activities are microbes involved in?
a) Decomposing dead organisms
b) Aiding the digestive processes of grazing animals
c) Capturing energy from the sun
d) All of the above
All of the above
When glucose is dissolved in water, the water is the ________ and the
glucose is the ________.
a) solvent, solute
b) solvent, solution
c) solute, solvent
d) solute, solution
Endospores are typically found in the genus: a) Streptococcus
Bacteria move by means of:
The shape of a bacterial cell is determined (and maintained) by the
a) cell membrane b) cell wall
d) slime layer
Which stain would be the best choice for detecting mycobacterium (the
bacteria responsible for tuberculosis and leprosy)?
a) simple stain
b) endospore stain
c) acid-fast stain
d) Gram stain
Bacteria with flagella all over their surface are said to be:
All of the following are considered microbes except:
The three fundamental particles of the atom are _____.
a) elements, molecules, and compounds
b) ions, cations, and anions.
c) proteins, lipids, and sugars
d) protons, neutrons, and electrons.
protons, neutrons, and electrons.
The charged, phosphate end of a membrane phospholipid is:
d) none of the above
Genetic information in bacteria is:
a) found in the nucleus
b) found only in RNA
c) found in DNA condensed by histones
d) sometimes found in the form of plasmids
sometimes found in the form of plasmids
Microbiology is the study of bacteria, algae, fungi, viruses and
protozoa. Most of these are single-celled, except for which
a) bacteria (some of which are multicellular) and algae
b) algae and fungi (some have many cells)
c) protozoa and fungi
d) bacteria and viruses
algae and fungi (some have many cells)
The counterstain in the endospore stain is _____.
a) malachite green
b) crystal violet
d) methylene blue
Charged atomswith electrostatic attraction are generally held
together by _____.
a) covalent bonds
b) ionic bonds
c) hydrogen bonds
d) municipal bonds
Ultraviolet light is a key component of:
a) bright-field microscopy
b) dark-field microscopy
c) phase-contrast microscopy
d) fluorescence microscopy
The atomic nucleus consists of:
a) cations and anions
b) protons, electrons and neutrons
c) protons and neutrons
d) solutes and colloids
protons and neutrons
Which of the following groups of organisms is not
What is true about the index of refraction?
a) If light rays are taken up by the object than it has a high index of refraction.
b) Refraction measures the frequency of the light as it reflects from a material.
c) Oil immersion lenses increase the problem of refraction.
d) Light will bend as it passes through two substances with different indices of refraction.
Light will bend as it passes through two substances with different indices of refraction.
a) releases material in the form of phagosomes.
b) is the process of taking materials into the cell.
c) directs material to the endoplasmic reticulum.
d) uses simple diffusion move material across the plasma membrane.
is the process of taking materials into the cell.
During diffusion, molecules _____.
a) move from hotter areas to cooler areas
b) move from areas of higher concentration to areas of lower concentration
c) move from areas of lower concentration to areas of higher concentration
d) expend energy to more around
move from areas of higher concentration to areas of lower concentration
A microorganism that causes disease is _______ .
In a Gram stain, the mordant is _____.
a) crystal violet
Eukaryotic cells add rigidity to their plasma membrane by including
what component in the membrane?
Amino acids in a protein are joined together by _____.
a) peptide bonds
b) hydrogen bonds
c) phosphodiester bonds
d) tertiary bonds
When light passes through an object, ________ of the light has
While a doctor may diagnose and treat a patient who presents with a
disease, an epidemiologist:
a) helps in the development and use of vaccines
b) investigates what organism is responsible for a particular patients disease
c) figures out how to use microorganisms to clean up the environment
d) studies the frequency and distribution of the disease in the community
studies the frequency and distribution of the disease in the community
A compound light microscope can generally see objects as no smaller
than a _____.
b) large protozoa
c) small bacterium
d) typical virus
Some bacteria can transfer DNA to another cell using:
a) conjugation pili
c) axial filaments
d) lophotrichous flagella
A typical bacterial cell has a salt concentration of about 1%. If the
cell is placed in a solution containing 10% salt, the net flow of
water will be _____.
a) out of the cell
b) into the cell
c) equally in and out of the cell
d) none of the above since water doesn't cross bacterial cell membranes
out of the cell
Which bacterial genus normally lacks a cell wall?
Which of the following cellular structures can be found in both
prokaryotic and eukaryotic cells?
a) Golgi apparatus
Penicillin controls the growth of bacteria by _____.
a) destroying cell membranes
b) preventing protein synthesis
c) removing cell walls
d) preventing peptidoglycan synthesis
preventing peptidoglycan synthesis
What is true about atomic weight?
a) It is the sum of the number of electrons and protons in an atom.
b) The higher the atomic weight the more likely an atom will form a chemical bond.
c) It is always a whole number.
d) Atoms of a particular element that have different atomic weights are called isotopes.
Atoms of a particular element that have different atomic weights are called isotopes.
In a properly executed Gram stain, Gram positive organisms appear
________ while Gram negative organisms appear ________.
a) pink, clear
b) pink, purple
c) purple, pink
d) purple, blue
All of the following statements agree with the germ theory of
a) microorganisms can invade other organisms and cause disease
b) maggots only grow on meat that is left in an open flask because microbes are transmitted by flies and do not spontaneously generate
c) disease causing organisms will spontaneously arise from decaying meat
d) disease is not caused by bad air or spirits
disease causing organisms will spontaneously arise from decaying meat
When light rays pass into an object but do not emerge, ________ has
Which statement about acids and bases is false?
a) A hydrogen ion (H+) is a proton.
b) Acids are proton acceptors.
c) Bases are proton acceptors
d) A hydroxyl ion donor is also a proton acceptor
Acids are proton acceptors.
The periplasmic space is found _____.
a) only in Gram positive organisms
b) between the nuclear area and the cell membrane
c) primarily in acid fast bacteria
d) between the innercell membrane and outer cell wall membrane
between the innercell membrane and outer cell wall membrane
The lens closest to your eyes during a microscopic examination is the
When light bends as it passes through an object, ________, of the
light has occurred.
The total number of protons in an atom is equal to its _____.
a) atomic weight
b) molecular weight
c) chemical weight
d) atomic number
Bacteria capsules can best be visualized by _______ staining.
b) crystal violet
The concept of putting microbes to work to clean up the environment
Inclusions found in bacteria generally would not include:
c) metachromatic granules
a) produced by gram positive rods act in the medium around the organism
b) are released by the golgi apparatus into the cytoplasm where they act
c) produced by gram negative rods act in the periplasmic space
d) two of the above
two of the above
In glycolysis, each molecule of glucose eventually produces ________
molecules of pyruvic acid.
a) one b) two c) three d) four
The transfer of DNA between bacterial cells by a virus is:
Which of the following is true about glycolysis?
a) The net yield of ATP is two ATPs for each molecule of glucose.
b) It provides cells with a relatively large amount of energy.
c) Four molecules of ATP are used in the initial phosphorylation steps.
d) The ATP that is used up during glycolysis is not considered in calculating the net yield of ATP.
The net yield of ATP is two ATPs for each molecule of glucose.
A bacterial population grows most rapidly during ________
Amino acids move from the cytoplasm to the ribosome with the help of
Organisms with special nutritional needs are said to be
d) none of the above
Which type of cell will generally shift to aerobic metabolism when
oxygen is available but will carry on fermentation otherwise?
a) aerotolerant anaerobes
b) facultative anaerobes
c) obligate anaerobes
d) obligate aerobes
Factors that affect the rate of enzyme catalyzed reactions
c) concentration of enzyme
d) all of the above
all of the above
Which of the following is not a carrier molecule that carries
hydrogen atoms or electrons in oxidative reactions?
a) refers to the increase in the size of a microbial cell
b) refers to the increase in the frequency of cell division
c) in a single generation time leads to double the cell size
d) in a single generation time leads to double the number of microbes.
in a single generation time leads to double the number of microbes.
This illustration represents: (deleted segment between two structural
genes, result in one strand)
a) conjugation or transformation b) transduction or mutation
c) genetic fusion
d) protoplast fusion or gene amplification
Most bacteria reproduce by:
a) sexual reproduction
b) binary fission
d) homologous recombination
The type of cell reproduction in which a small, new cell develops
from the surface of an existing cell and then separates from the
parent cell is known as ________ and is the normal mode of replication
in _____ .
a) binary fission, bacteria
b) binary fission, yeast
c) budding, bacteria
d) budding, yeast
This molecule is used in the process of _____.
(mRNA codon + anticodon / amino acid accepter arm)
a) DNA replication
d) protein synthesis
Serial dilutions are used to:
a) slow down the growth of microbes
b) speed up the growth of microbes
c) obtain bacterial cultures at several different concentrations d) form bacterial colonies
obtain bacterial cultures at several different concentrations
Which of the following processes requires contact between donor and
A viral cycle, which ends with the rupture of the cell and release of
new viral particles, is the:
a) temperate cycle
b) lytic cycle
c) lysogenic cycle
d) prophage cycle
Competitive inhibition of enzymes occurs when the inhibitor:
a) binds to the active site of the enzyme.
b) binds to the allosteric site of the enzyme.
c) inhibitor changes the shape of the enzyme.
d) inhibitor is acted upon by the enzyme.
binds to the active site of the enzyme.
All of the following are electron acceptors for anaerobic
a) carbon dioxide
c) nitrate ions
d) sulfate ions
Bacterial conjugation is an example of _____.
b) vertical gene transfer
c) horizontal gene transfer
d) bacterial transformation
horizontal gene transfer
Transcription results in the formation of what type of new
Genes with different information at the same locus are called
When genes are passed on from parent to offspring, which of the
following events has taken place?
a) horizontal gene transfer
c) vertical gene transfer
d) retrograde gene transfer
vertical gene transfer
The initial substrate molecule for the Krebs cycle is:
a) pyruvic acid
c) acetic acid
Which reaction takes place in the mitochondrial membrane?
c) Krebs cycle
d) Electron transport chain
Electron transport chain
Which of the following is most likely to have evolved to live in the
deep layers of mud, where there is a complete lack of free
a) Obligate aerobe
b) Obligate anaerobe
c) Facultative anaerobe
d) Aerotolerant anaerobe
Which one of the following pairs is mismatched?
a) Alcohol - Fermentation
b) Pyruvate - Glycolysis
c) Carbon dioxide - Glycolysis d) Oxaloacetic acid - Krebs cycle
Carbon dioxide - Glycolysis
When cells are placed in a hypertonic environment they will undergo
b) no change in size
c) swelling of the cell which is contained by the cell wall
Hybridomas are used to produce large quantities of _____.
a) restriction enzymes
b) monoclonal antibodies
d) natural insecticides
With regard to the lac operon, which of the following is false under
conditions of low (or no) lactose?
a) The RNA polymerase cannot transcribe structural genes
b) The repressor is bound to the operator
c) Lactose is not bound to the repressor
d) RNA polymerase can bind to the promoter
RNA polymerase can bind to the promoter
The information for a gene on a chromosome is used to create ____ which then moves to the ribosome to sere as a template for protein synthesis.
A culture that contains only a single species of organism is known as
a) pure culture
b) Koch culture
c) mixed culture
d) contaminated culture
When an E. coli cell contains high levels of lactose, the lactose
will bind with the _____.
d) RNA polymerase
In the stationary phase of bacterial growth:
a) the number of newly generated cells is greater than the number of dying cells b) the number of newly generated cells is less than the number of dying cells
c) the number of newly generated cells is the same as the number of dying cells
d) none of the above
the number of newly generated cells is the same as the number of dying cells
The end product of glycolysis is:
b) 1,3 diphosphoglyceric acid
c) phosphoenolpyruvic acid
d) pyruvic acid
Which of the following properties are exclusive to rRNA?
a) Combines with specific proteins to form ribosomes
b) Carries information from DNA for synthesis of a protein
c) Molecules contain an anticodon
d) Contains the nucleotide thymine
Combines with specific proteins to form ribosomes
RNA polymerase uses ________ as a template to synthesize ________
a) RNA, proteins
b) RNA, DNA
c) DNA, RNA
d) DNA, proteins
At which temperature do enzymes begin to denature?
a) 20 degrees Celsius
b) 30 degrees Celsius
c) 40 degrees Celsius
d) 50 degrees Celsius
40 degrees Celsius
During replication DNA is synthesized by _____.
a) DNA polymerase
b) RNA polymerase
An anticodon would be found in/on a ________ molecule.
c) the lagging strand
Photoautotrophs obtain energy from:
a) light and use carbon dioxide as a carbon source
b) organic molecules and use carbon dioxide as a carbon source
c) inorganic substances and use carbon dioxide as a carbon source
d) light and use organic substances as a carbon source
light and use carbon dioxide as a carbon source
Within a bacterial endospore, the spore is most closely surrounded by
a) spore membrane
c) cell membrane
d) spore coat
The genetic information needed for a cell to participate in
conjugation resides in the DNA of a cell's _____.
a) bacterial chromosome
b) F plasmid
c) F pilus
A plasmid is a/an _____.
a) extrachromosomal piece of DNA
b) chromosomal site to which genetic activity can be traced
c) body found in the cytoplasm that directs protein synthesis
d) molecule that carries the genetic message of the chromosomal DNA
extrachromosomal piece of DNA
Capnophiles grow best under conditions of _____.
a) high carbon dioxide
b) low carbon dioxide
c) high osmotic pressure
d) low osmotic pressure
high carbon dioxide
Oxidation is defined as the ________ while reduction is the ________
a) gain of electrons, loss of protons
b) loss of electrons, gain of protons
c) loss of electrons, gain of electrons
d) loss of protons, gain of protons
loss of electrons, gain of electrons
A bacterium that is transformed:
a) cannot form a conjugation pilus
b) has acquired naked DNA from the environment
c) will probably die within 48 hours
d) if injected, it always will result in the death of a mouse
has acquired naked DNA from the environment
In the electron transport chain, the energy to make ATP comes
directly from _____.
c) both FAD and NADH
d) neither FAD nor NADH
both FAD and NADH
Plasmids can do which of the following?
a) direct synthesis of conjugation pili
b)provide resistances to certain antibiotics
c) induce the formation of tumors in plants
d) all of the above are functions of various plasmids
all of the above are functions of various plasmids
a) must be present for a bacteria to stay alive and reproduce
b) are small segments of DNA that have the ability to move from one position to another
c) contain genetic information that is helpful but not necessary for survival
d) are always circular and only one is present in each bacteria
must be present for a bacteria to stay alive and reproduce
Sulfa drugs bind to the active site of the enzyme which normally
converts para-amino benzoic acid (PABA) to folic acid, preventing the
production of folic acid and, eventually purine synthesis. In this
case, the sulfa drug is acting as a/an:
a) allosteric inhibitor
b) competitive inhibitor
c) noncompetitive inhibitor
d) uncompetitive inhibitor
Where would you expect to find a barophile?
a) At the bottom of the ocean
b) In unpasteurized milk
c) In the large intestine
d) In sewage
At the bottom of the ocean
a) grow best when the environment has a small amount of carbon dioxide.
b) grow best when the environment has a small amount of free oxygen.
c) need a high concentration of carbon dioxide.
d) need a high concentration of oxygen.
grow best when the environment has a small amount of free oxygen.
An obligate psychrophile would produce a turbid culture at ________
Most human pathogens are _____.
As electrons are passed from carrier to carrier, their energy
changes. At which point in the chain, would you expect the energy of
the electrons to be the lowest?
Organisms which get their carbon from other organisms are:
In an experiment such as Griffith's pneumococcal experiment which of
the following, when injected into a mouse, would result in its
a) Heat-killed, smooth pneumoccocci
b) Live, rough pneumococci
c) A mixture of heat killed smooth pneumococci and live rough pneumococci
d) A mixture of heat killed rough pneumococci and live rough pneumococci
A mixture of heat killed smooth pneumococci and live rough pneumococci
A virus which incorporates its DNA into the DNA of its host organism
is existing as a _____.
a) virulent phage
c) lytic phage
d) none of the above
In a culture containing both F- and F+ cells, which of the following
will occur if we wait long enough?
a) No conjugation will occur
b) The cells will all become genetically identical
c) All F- will become F+ cells
d) All F+ cells will become F- cells
All F- will become F+ cells
In aerobic respiration, the final electron acceptor is:
d) coenzyme Q
An enzyme-substrate complex forms when substrate binds to an enzyme
at the enzyme's ______ site.
In eukaryotes, transcription takes place in the ________ while
translation takes place in the ________.
a) nucleus, nucleus
b) nucleus, cytoplasm
c) cytoplasm, nucleus
d) cytoplasm, cytoplasm
During the process of lysogeny:
a) a phage integrates into the chromosome of the bacterium
b) a bacterium takes up DNA from the media
c) new phage particles are assembled in the host bacterium
d) a bacterium is split open to release new phage particles
a phage integrates into the chromosome of the bacterium
A typical transposon is flanked by:
a) resistance factors
b) inverted repeat terminals
c) RTF genes
d) repressor sites
inverted repeat terminals
Pyruvic acid is metabolized in the absence of oxygen during the
d) dark reactions
The first step in protein metabolism is the breakdown of proteins
b) fatty acids
c) amino acids
Which of the following statements is true?
a) During DNA replication the leading strand serves as template for replication of lagging strand.
b) Fragments on the lagging strand are joined together by DNA ligase.
c) A bacterial chromosome is made up of individual units called Okazaki fragments.
d) Two strands of double helix combine by base pairing in a parallel fashion.
Fragments on the lagging strand are joined together by DNA ligase.
An ideal antimicrobial agent will be soluble in body fluids.
Enveloped animal viruses typically leave the host cell by:
a) host cell lysis
b) host cell rupture
d) animal viruses never leave the host cell
A eukaryotic, unicellular organism with no cell wall would be classified as ____.
The reason that retroviruses can direct the formation of DNA from RNA is because most retroviruses contain the following enzyme.
a) RNA polymerase
b) DNA polymerase
c) DNA ligase
d) reverse transcriptase
A strain is a subgroup of a ______.
Classification is necessary to _____.
a) establish criteria for identifying organisms
b) arrange related organisms into groups
c) provide information on how organisms evolved
d) All of the above
All of the above
Antibiotics that bind to RNA polymerase ______.
a) act as base analogs
b) inhibit of cell wall synthesis
c) disrupt of cell membrane function
d) inhibit transcription
Which of the following is not an example of a plantlike protist?
Cells walls in fungi are often made of ______.
d) calcium carbonate
Viruses have some of the properties of cellular life forms. Which of
the following is a characteristic of all organisms except
a) presence of a plasma membrane
b) capable of mutation
c) ability to reproduce inside a living host
d) grow in response to their environmental conditions
presence of a plasma membrane
Which of the following represents the correct order of steps in a
typical virus replication cycle?
a) maturation adsorption penetration release synthesis
b) adsorption penetration release maturation synthesis
c) adsorption penetration synthesis maturation release
d) adsorption penetration maturation synthesis release
adsorption penetration synthesis maturation release
Which of the following directly pertain to inhibition of cellular
protein synthesis by antimicrobial agents?
A) cellular cytoplasm is lost
B) binding and inhibition of RNA polymerase
C) imitation or molecular mimicry of normal molecules
D) interferes with accurate translation of mRNA message
interferes with accurate translation of mRNA message
An organism that lives at the expense of another organism is a
Which of the following statements about protists is true?
a) The protozoan responsible for malaria is classified as a ciliate.
b) Eutrophication occurs when protists stop growing in a body of water.
c) Amoeba move by means of cilia.
d) All protists are eukaryotic.
All protists are eukaryotic.
Protozoa that move using flagella are members of the _____.
Protozoans found in the human intestinal tract would most likely be ______.
A mechanical vector:
a) lives on or in another organism at the expense of the host
b) simply carries microbes on the outside of its body
c) reproduces as an asexual form in this host
d) infects by mechanical insertion of a syringe
simply carries microbes on the outside of its body