MICROBIOLOGY A Systems Approach 4TH EDITION BY COWAN – TEST BANK A+

Description

Multiple Choice Questions

1. Viruses exhibit all the following except
2. definite shape.
3. metabolism.
4. genes.
5. ability to infect host cells.
6. ultramicroscopic size.

1. Host cells of viruses include
2. humans and other animals.
3. plants and fungi.
4. bacteria.
5. protozoa and algae.
6. All of the choices are correct.

1. Viruses
2. cannot be seen in a light microscope.
3. are prokaryotic.
4. contain 70S ribosomes.
5. undergo binary fission.

1. Viral capsids are made from subunits called
2. envelopes.
3. spikes.
4. capsomeres.
5. prophages.
6. peptones.

1. Helical and icosahedral are terms used to describe the shape of a viral
2. spike.
3. capsomere.
4. envelope.
5. capsid.
6. core.

1. A/n _____ is the protein shell around the nucleic acid core of a virus.
2. capsomere
3. capsid
4. spike
5. envelope
6. monolayer

1. One of the principal viral capsid shapes is a 20-sided figure with 12 evenly spaced corners referred to as a/n _____ capsid.
2. spiked
3. complex
4. icosahedral
5. helical
6. buckeyball

1. A naked virus only has a/n
2. capsid.
3. capsomere.
4. nucleocapsid.
5. envelope.
6. antigenic surface.

1. Which of the following is not a typical capsid shape?
2. tetrahedral
3. complex
4. helical
5. icosahedron
6. viroid.

1. All of the following pertain to virus envelopes except
2. gained as a virus leaves the host cell membrane.
3. gained as a virus leaves the nuclear membrane.
4. contain special virus proteins.
5. help the virus particle attach to host cells.
6. located between the capsid and nucleic acid.

1. Viral spikes
2. are always present on enveloped viruses.
3. attach the viral capsid and envelope.
4. allow bacteria to evade host defenses.
5. are derived from host proteins.
6. are for recognition among the various types of viruses.

1. The core of every virus particle always contains
2. DNA.
3. capsomeres.
4. enzymes.
5. DNA and RNA.
6. either DNA or RNA.

1. Which of the following is not associated with every virus?
2. envelope
3. capsomeres
4. capsid
5. nucleic acid
6. genome

1. Viral nucleic acid types include:
2. double-stranded DNA
3. single-stranded DNA
4. double-stranded RNA
5. single-stranded RNA
6. All of the choices are correct.

1. Reverse transcriptase synthesizes
2. a positive RNA strand from a negative RNA strand.
3. a negative RNA strand from a positive RNA strand.
4. viral RNA from DNA.
5. viral DNA from RNA.

1. A negative RNA virus must first
2. synthesize a DNA copy of its genome.
3. synthesize a negative RNA copy of its genome.
4. synthesize a positive RNA copy of its genome.
5. transcribe reverse transcriptase.
6. transcribe RNA polymerase.

1. Viruses with _____-sense RNA contain the correct message for translation, while viruses with _____-sense RNA must first be converted into a correct message.
2. positive; negative
3. negative; positive
4. primary; secondary
5. secondary; primary
6. intermediate; primary

1. Classification of viruses into families involves determining all the following characteristics except
2. type of nucleic acid.
3. type of capsid.
4. presence of an envelope.
5. biochemical reactions.
6. number of strands in the nucleic acid.

1. Which of the following represents a virus family name?
2. Herpes simplex virus
3. Herpesviridae
4. Picornavirus
5. Enterovirus
6. Hepatitis B virus

1. Which of the following is not a viral order in the classification system?
2. Caudovirales
3. Vaccinia virus
4. Nidovirales
5. Mononegavirales

1. The correct sequence of events in viral multiplication is:
2. penetration, uncoating, synthesis, adsorption, assembly, release
3. uncoating, penetration, synthesis, assembly, absorption, release
4. adsorption, penetration, uncoating, synthesis, assembly, release
5. assembly, synthesis, uncoating, release, penetration, adsorption
6. adsorption, release, synthesis, uncoating, assembly, penetration

1. Viruses acquire envelopes around their nucleocapsids during
2. replication.
3. assembly.
4. adsorption.
5. release.
6. penetration.

1. In general, most DNA viruses multiply in the host cell’s _____, while most RNA viruses multiply in the host cell’s _____.
2. nucleus; cytoplasm
3. cytoplasm; cell membrane
4. cell membrane; cytoplasm
5. cytoplasm; nucleus
6. nucleus; endoplasmic reticulum

1. Host range is limited by
2. type of nucleic acid in the virus.
3. age of the host cell.
4. type of host cell receptors on cell membrane.
5. size of the host cell.

1. Oncogenic viruses include all the following except
2. hepatitis B virus.
3. measles virus.
4. Papillomavirus.
5. HTLV-I and HTLV-II viruses.
6. Epstein-Barr virus.

1. Which of the following is a type of cytopathic effect?
2. inclusions in the nucleus
3. multinucleated giant cells
4. inclusions in the cytoplasm
5. rounding of cells
6. All of the choices are correct.

1. The envelope of enveloped viruses
2. is identical to the host plasma membrane.
3. is only composed of host endomembrane.
4. always includes spikes.
5. is obtained by viral budding or exocytosis.
6. makes the virus very susceptible to drug therapy.

1. Viruses attach to their hosts via
2. host glycoproteins.
3. host phospholipids.
4. viral phospholipids.
5. viral flagella.
6. carbohydrate attachments of the viral capsid.

1. Viral tissue specificities are called
2. ranges.
3. virions.
4. receptacles.
5. tropisms.
6. uncoating.

1. The process of dissolving the envelope and capsid to release the viral nucleic acid is
2. adsorption.
3. penetration.
4. uncoating.
5. synthesis.
6. assembly.

1. Which of the following occurs during assembly?
2. nucleocapsid is formed
3. new viral nucleic acid is formed
4. viral spikes insert in host cell membrane
5. nucleocapsid is formed and viral spikes insert in host cell membrane
6. the viral envelope and the host cell membrane fuse

1. Mammalian viruses capable of starting tumors are
2. chronic latent viruses.
3. oncoviruses.
4. syncytia.
5. inclusion bodies.
6. cytopathic.

1. Persistent viruses that can reactivate periodically are
2. chronic latent viruses.
3. oncoviruses.
4. syncytia.
5. inclusion bodies.
6. cytopathic.

1. Which of the following is not a characteristic of a transformed cell?
2. viral nucleic acid integrated into host DNA
3. decreased growth rate
4. alterations in chromosomes
5. changes in cell surface molecules
6. capacity to divide indefinitely

1. New, nonenveloped virus release occurs by
2. lysis.
3. budding.
4. exocytosis.
5. both lysis and budding.
6. both budding and exocytosis.

1. What structures are used by bacteriophages to attach to host cell receptors?
2. viral sheaths
3. tail fibers
4. nucleic acids
5. capsid heads

1. Which of the following is incorrect about prophages?
2. present when the virus is in lysogeny
3. formed when viral DNA enters the bacterial chromosome
4. replicated with host DNA and passed on to progeny
5. cause lysis of host cells
6. occur when temperate phages enter host cells

1. T-even phages
2. include the poxviruses.
3. infect Escherichia coli cells.
4. enter host cells by engulfment.
5. have helical capsids.

1. The event that occurs in bacteriophage multiplication that does not occur in animal virus replication is
2. adsorption to the host cells.
3. injection of only the viral nucleic acid into the host cell.
4. host cell synthesis of viral enzymes and capsid proteins.
5. assembly of nucleocapsids.
6. replication of viral nucleic acid.

1. Viruses that cause infection resulting in alternating periods of activity with symptoms and inactivity without symptoms are called
2. latent.
3. oncogenic.
4. prions.
5. viroids.
6. delta agents.

1. Uncoating of viral nucleic acid
2. does not occur in bacteriophage multiplication.
3. involves enzymatic destruction of the capsid.
4. occurs during penetration in the multiplication cycle.
5. occurs before replication.
6. All of the choices are correct.

1. In transduction, the viral genome
2. initiates lysis of the host.
3. includes DNA from the previous host.
4. is replicated in the cytoplasm.
5. is replicated in the nucleus.

1. Lysogeny refers to
2. altering the host range of a virus.
3. latent state of herpes infections.
4. virion exiting host cell.
5. viral genome inserting into bacterial host chromosome.

1. Viruses that infect bacteria are specifically called
2. viroids.
3. prions.
4. bacteriophages.
5. satellite viruses.

1. During lysogeny, an inactive prophage state occurs when the viral DNA is inserted into the host
2. cytoplasm.
3. nucleus.
4. nucleolus.
5. DNA.
6. cell membrane.

1. What type of phage enters an inactive prophage stage?
2. primary
3. secondary
4. temperate
5. temporary
6. transformed

1. The activation of a prophage is called
2. activation.
3. lysogeny.
4. transformation.
5. induction.
6. adsorption.

1. When a bacterium acquires a trait from its temperate phage, it is called
2. transformation.
3. lysogenic conversion.
4. viral persistence.
5. transcription.
6. translation.

1. Which of the following will not support viral cultivation?
2. live lab animals
3. embryonated bird eggs
4. primary cell cultures
5. continuous cell cultures
6. All of the choices will support viral cultivation.

1. Visible, clear, well-defined patches in a monolayer of virus-infected cells in a culture are called
2. patches.
3. buds.
4. plaques.
5. cytopathic effects.
6. pocks.

1. Viral growth in bird embryos can cause discrete, opaque spots in the embryonic membranes called
2. patches.
3. buds.
4. plaques.
5. cytopathic effects.
6. pocks.

1. Cells grown in culture form a/n
2. monolayer.
3. bilayer.
4. aggregate.
5. plaque.

1. Diagnosis of viral infections sometimes involves analyzing the patient’s blood for specific _____ that the immune system produces against the virus.
2. glycoproteins
3. antibodies
4. complement proteins
5. antigens

1. Freshly isolated animal tissue that is placed in a growth medium and allowed to produce a cell monolayer is referred to as a/n _____ cell culture.
2. initial
3. primary
4. secondary
5. continuous
6. positive

1. A common method for cultivating viruses in the lab is to use in vitro systems called _____ cultures.
2. embryo
3. cell
4. plaque
5. bacteriophage
6. egg

1. Infectious protein particles are called
2. viroids.
3. phages.
4. prions.
5. oncogenic viruses.
6. spikes.

1. Infectious naked strands of RNA that affect plants are called
2. viroids.
3. phages.
4. prions.
5. oncogenic viruses.
6. spikes.

1. Creutzfeldt-Jacob disease is
2. caused by a chronic latent virus.
3. initiated by an oncogenic virus.
4. caused by a viroid.
5. a spongiform encephalopathy of humans.
6. also called “mad cow disease.”

1. Satellite viruses are
2. also called viroids.
3. dependent on other viruses for replication.
4. the cause of spongiform encephalopathies.
5. significant pathogens of plants.

1. Two noncellular agents, smaller than viruses, are infectious proteins called _____ and infectious RNA strands called _____.
2. prions; capsomeres
3. virions; prions
4. viroids; phages
5. prions; phages
6. prions; viroids

1. Who developed a rabies vaccine after realizing the disease was caused by something smaller than a bacterium?
2. Leewonhoek
3. Koch
4. Pasteur
5. Cohn
6. Ivanovski

1. The primary purpose/s of viral cultivation is/are to
2. isolate and identify viruses in clinical specimens.
3. prepare viruses for vaccines.
4. do detailed research on viral structure, lifestyle, genetics, and effects on host cells.
5. perform wide-scale harvesting of viruses.
6. All of the choices are correct.

True / False Questions

1. When a virus enters a host cell, the viral genes redirect the genetic and metabolic activities of the host cell.

1. Viruses are used to produce vaccines for prevention of certain viral infections.

1. Viruses are considered ultramicroscopic because they range in size from 2 mm to 450 mm.

1. A fully formed virus that can cause an infection in a host cell is called a virion.

1. Spikes are glycoproteins that can be found projecting from the viral capsid.

1. Each virus is assigned a genus status based on its host, target tissue, and type of disease it causes.

1. A specific animal virus has the ability to attach to and enter almost any animal host cell.

1. Viral spikes are inserted into the host cell membrane before budding or exocytosis.

1. Prophages can be activated into viral replication and enter the lytic cycle.

1. Bacteriophages do not undergo adsorption to specific host cell receptors prior to penetration.

1. Viruses are the most common cause of acute infections that do not result in hospitalization.

1. The adeno-associated virus (AAV) and the delta agent are prions.

1. Viruses are simple, noncellular, and lack mRNA.

1. Viruses mutate and some have not been discovered.

1. Viruses are not filterable.

1. Viruses are unable to multiply outside of a host cell.

Multiple Choice Questions

1. A treatment for bacterial infections from the early 20th century has made a comeback-the use of bacterial viruses to eliminate bacterial infections. Which explanation most accurately describes this mechanism of action behind this treatment?
2. A wide variety of bacteria cause a large percentage of human infections, producing much sickness and death.
3. Viruses can infect bacteria, transferring pathogenic genes. The viral genes can then be suppressed, causing the bacteria to not replicate viruses.
4. The attachment structures on the virus and the receptors on the host cells make for exquisite specificity of viruses for particular bacterial species.
5. Antibiotic resistance in humans is on the increase, so using a different kind of therapy is more beneficial.

1. Some animals can become infected with multiple influenza virus strains usually associated with other animals. Which statement below describes the result of these infections?
2. A new novel strain of flu may be produced, for which the human population has no immunity.
3. Major genetic variations in the flu viruses can be reproduced.
4. The viral genomes within the host cells can become recombined.
5. All of the above are possible outcomes.

1. How are viroids transmitted?
2. respiratory secretions
3. sex
4. plant seeds
5. blood products

1. Tamiflu is a common medication given for influenza treatment, its action being to protect and block sialic acid molecules on the surfaces of host cells and influenza virus envelopes as they leave the cell. Which statement reflects the mechanism of Tamiflu’s action?
2. Tamiflu blocks protein synthesis of the viral genome.
3. Tamiflu interferes with the replication of +ssRNA from the -ssRNA genome of the flu virus.
4. Tamiflu interferes with the release of the budding viruses from the infected host cells.
5. Tamiflu interferes with the metabolic properties of the virus.

1. Successful anti-HIV drug therapies today work by blocking the action of viral reverse transcriptase. Select which step of virus multiplication that would be directly blocked by this mechanism:
2. adsorption
3. penetration
4. synthesis
5. assembly
6. release

1. You are working in a laboratory that is studying a newly isolated virus. Your job is to culture the virus using in vitro methods. Upon observing your inoculated tissue culture specimen one day, you notice clumps of cells growing on top of the original monolayer of cells. Microscopic analysis of stained cells from the culture reveal an alteration in host cell membrane protein content and chromosomal structure. Based upon this information, you hypothesize that the virus you are studying is:
2. a bacteriophage
3. a prion
4. a viroid
5. an oncovirus
6. a satellite virus

1. Select the statement that most accurately describes the action of antimicrobial drugs today.
2. Antiviral drug treatment is more effective than vaccination against a viral disease.
3. Effective antiviral drugs have a long history of development and use.
4. Antiviral drugs often result in toxic side effects due to their inhibition of host cell activity.
5. The development of antiviral drug resistance has not been observed, as compared to the high rate of antibiotic resistance seen today.

Chapter 07

Microbial Nutrition, Ecology, and Growth

Multiple Choice Questions

1. Microorganisms require large quantities of ______ for use in cell structure and metabolism:
2. electrolytes
3. macronutrients
4. water
5. growth factors
6. trace elements

1. Microorganisms require small quantities of ______ for enzyme function and maintenance of protein structure:
2. electrolytes
3. macronutrients
4. water
5. growth factors
6. trace elements

1. What compound has the highest concentration in a cell?
2. CO2
3. CH4
4. H2O
5. glucose
6. NH3

1. Most of the dry weight of a microbial cell is from
2. inorganic compounds.
3. minerals.
4. water.
5. organic compounds.
6. salts.

1. Which of the following is not a major element of a microbial cell?
2. copper
3. carbon
4. hydrogen
5. nitrogen
6. oxygen

1. An organic nutrient that cannot be synthesized by the organism and must be provided is called a/n
2. element.
3. macronutrient.
4. compound.
5. growth factor.
6. trace element.

1. An important mineral ion of the cytochrome pigments of cellular respiration is
2. iron.
3. zinc.
4. calcium.
5. magnesium.
6. potassium.

1. An important mineral ion that is a component of chlorophyll, and stabilizer of membranes and ribosomes is
2. iron.
3. zinc.
4. calcium.
5. magnesium.
6. potassium.

1. Calcium is required for bacteria because it
2. stabilizes the cell wall.
3. stabilizes the ribosomes.
4. stabilizes the nucleoid.
5. maintains cellular pH.
6. makes strong cell walls.

1. Growth factors
2. are inorganic.
3. are synthesized by the organism.
4. contain elemental oxygen.
5. cannot be synthesized by the organism.
6. All of the choices are correct.

1. An organism that uses CO2 for its carbon needs and sunlight for its energy needs would be called a
2. heterotroph.
3. photoautotroph.
4. chemoheterotroph.
5. saprobe.
6. halotroph.

1. The methanogens, producers of methane gas, require environments that
2. have sunlight.
3. are very acidic.
4. have abundant oxygen and CO2.
5. are extremely cold.
6. are anaerobic with hydrogen gas and CO2.

1. Organisms that feed on dead organisms for nutrients are called
2. saprobes.
3. parasites.
4. autotrophs.
5. lithoautotrophs.
6. phototrophs.

1. The type of photosynthesis that does not produce oxygen
2. occurs in cyanobacteria.
3. does not require CO2 as a reactant.
4. occurs in purple and green sulfur bacteria.
5. does not require sunlight.
6. occurs in algae and plants.

1. Aerobic respiration is an example of
2. photosynthesis.
3. methanoheterophy.
4. photoheterotrophy.
5. chemoheterotrophy.
6. photoautotrophy.

1. Microorganisms that live in severe habitats, such as very hot, acidic, or salty environments, are called
2. thermophiles.
3. halophiles.
4. psychrophiles.
5. extremophiles.
6. barophiles.

1. Organisms called _____ live on or in the body of a host, and cause some degree of harm.
2. mesophiles
3. thermophiles
4. commensals
5. pathogens
6. halophiles

1. The term obligate refers to
2. the ability to exist in a wide range of conditions.
3. existing in a very narrow niche.
4. using chemicals for energy production.
5. using light for energy production.
6. using oxygen for metabolism.

1. The term facultative refers to
2. the ability to exist in a wide range of conditions.
3. existing in a very narrow niche.
4. using chemicals for energy production.
5. using light for energy production.
6. using oxygen for metabolism.

1. The movement of molecules from an area of high concentration to an area of lower concentration is called
2. facilitated diffusion.
3. diffusion.
4. active transport.
5. osmosis.
6. endocytosis.

1. Diffusion of water through a semipermeable membrane is called
2. facilitated diffusion.
3. diffusion.
4. active transport.
5. osmosis.
6. endocytosis.

1. The movement of substances from lower to higher concentration across a semipermeable membrane that must have a specific protein carrier and cell expenditure of energy is called
2. facilitated diffusion.
3. diffusion.
4. active transport.
5. osmosis.
6. endocytosis.

1. The movement of substances from higher to lower concentration across a semipermeable membrane that must have a specific protein carrier but no energy expenditure is called
2. facilitated diffusion.
3. diffusion.
4. active transport.
5. osmosis.
6. endocytosis.

1. The process by which a cell uses ATP to enclose a substance in its membrane, by forming a vacuole and engulfing it, is called:
2. facilitated diffusion.
3. diffusion.
4. active transport.
5. osmosis.
6. endocytosis.

1. Bacteria living in a freshwater stream that are moved to salty seawater would
2. be in a hypotonic solution.
3. gain water.
4. be in an isotonic solution.
5. become dehydrated due to the loss of water.

1. Which of the following microorganisms would find hypotonic conditions most detrimental?
2. bacteria
3. protozoa
4. fungi
5. algae
6. cyanobacteria

1. Which of the following require the cell to use ATP?
2. facilitated diffusion
3. diffusion
4. endocytosis
5. osmosis

1. Contractile vacuoles are
2. used to expel excess water from cells.
3. found in bacterial cells.
4. important to certain organisms in hypertonic environments.
5. protein carriers in cell membranes.
6. used to bring solutes into a cell.

1. Nutrient absorption is mediated by the
2. cell wall.
3. peptidoglycan layer.
4. proteins in the periplasmic space.
5. cell membrane.
6. nuclear membrane.

1. Facilitated diffusion is limited by
2. substrate concentration.
3. carrier proteins in the membrane.
4. size of the pores in the membrane.
5. osmotic pressure.
6. size of the cell.

1. When whole cells or large molecules in solution are engulfed by a cell, this endocytosis is specifically termed
2. pinocytosis.
3. phagocytosis.
4. facilitated transport.
5. facilitated diffusion.
6. exocytosis.

1. Mediated transport of polar molecules and ions across the plasma membrane utilizes a/n _____ carrier that will bind to the substance, effecting a conformational change that allows movement across the membrane.
2. protein
3. lipid
4. porin
5. enzyme

1. In _____ conditions, the cell wall will help prevent the cell from bursting.
2. hypertonic
3. hypotonic
4. isotonic
5. mesotonic

1. Cultures of a bacterial species were incubated on the shelf of a refrigerator (5oC), out on a lab bench top (22oC), on the shelf of a 37 C incubator, and on the shelf of a 50 C incubator. After incubation, there was no growth at 37 C and 50 C, slight growth in the refrigerator, and abundant growth on the lab bench top. What term could be used for this species?
2. halophile
3. mesophile
4. anaerobe
5. psychrotroph
6. capnophile

1. Cultures of a bacterial species were incubated in a standard incubator, in an anaerobic jar, and in a candle jar. After incubation, there was moderate growth of cultures in the candle and anaerobic jars, but heavy growth of the culture in the incubator. This species is a/n
2. aerobe.
3. anaerobe.
4. facultative anaerobe.
5. microaerophile.
6. capnophile.

1. A microorganism that has an optimum growth temperature of 37 C, but can survive short exposure to high temperatures is called a/n
2. extremophile.
3. thermophile.
4. psychrophile.
5. facultative psychrophile.
6. thermoduric microbe.

1. An organism that grows slowly in the cold but has an optimum growth temperature of 32 C is called a/n
2. extremophile.
3. thermophile.
4. psychrophile.
5. facultative psychrophile.
6. thermoduric.

1. An organism with a temperature growth range of 45 C to 60 C would be called a/n
2. extremophile.
3. thermophile.
4. psychrophile.
5. facultative psychrophile.
6. thermoduric.

1. Human pathogens fall into the group called
2. psychrophiles.
3. thermophiles.
4. halophiles.
5. mesophiles.
6. acidophiles.

1. All of the following could find a location in or on body tissues suitable for growth except
2. psychrophiles.
3. anaerobes.
4. facultative anaerobes.
5. mesophiles.
6. capnophiles.

1. A microorganism that does not have catalase or superoxide dismutase would find it difficult to live in an environment with
2. carbon dioxide.
3. oxygen.
4. high salt.
5. temperatures above 37 C.
6. high acidity.

1. A microaerophile
2. grows best in an anaerobic jar.
3. grows with or without oxygen.
4. needs normal atmospheric levels of oxygen.
5. requires a small amount of oxygen but won’t grow at normal atmospheric levels of oxygen.

1. The toxic superoxide ion is converted to harmless oxygen by two enzymes,
2. catalase and hydrogen peroxidases.
3. superoxide dismutase and hydrogen peroxidase.
4. superoxide dismutase and catalase.
5. catalase and oxidase.
6. superoxide dismutase and oxidase.

1. An organism that can use gaseous oxygen in metabolism and has the enzymes to process toxic oxygen products is a/n
2. aerobe.
3. obligate aerobe.
4. facultative anaerobe.
5. microaerophile.
6. obligate anaerobe.

1. An organism that can exist in both oxygen and oxygen-free environments is a/n
2. aerobe.
3. obligate aerobe.
4. facultative anaerobe.
5. microaerophile.
6. obligate anaerobe.

1. An organism that cannot tolerate an oxygen environment is a/n
2. aerobe.
3. obligate aerobe.
4. facultative anaerobe.
5. microaerophile.
6. obligate anaerobe.

1. An organism that cannot grow without oxygen is a/n
2. aerobe.
3. obligate aerobe.
4. facultative anaerobe.
5. microaerophile.
6. obligate anaerobe.

1. What type of media is used to demonstrate oxygen requirements of microbes?
2. blood agar
3. thioglycollate
4. sulfite polymyxin sulfadiazine
5. sodium chloride

1. A halophile would grow best in
2. acid pools.
3. fresh water ponds.
4. hot geyser springs.
5. arid, desert soil.
6. salt lakes.

1. A barophile would grow best in
2. acid pools.
3. deep oceans.
4. hot geyser springs.
5. arid, desert soil.
6. salt lakes.

1. E. coli bacteria that normally live in the human large intestines and produce vitamin K that the body uses would be best termed a _____ relationship.
2. parasitic
3. saprobic
4. antagonistic
5. mutualistic

1. The production of antibiotics is a form of antagonism called
2. symbiosis.
3. satellitism.
4. antibiosis.
5. mutualism.
6. synergism.

1. When microbes live independently but cooperate and share nutrients, it is called
2. symbiosis.
3. satellitism.
4. antibiosis.
5. mutualism.
6. synergism.

1. When microbes are in a close nutritional relationship, and one benefits but the other is not harmed, it is called
2. symbiosis.
3. satellitism.
4. commensalism.
5. mutualism.
6. synergism.

1. A change in one partner, in a close relationship, that leads to a change in the other partner is
2. symbiosis.
3. coevolution.
4. antibiosis.
5. mutualism.
6. synergism.

1. The time interval from parent cell to two new daughter cells is called
2. binary fission.
3. growth curve.
4. generation time.
5. death phase.
6. culture time.

1. The phase of the bacterial growth curve in which the rate of multiplication equals the rate of cell death is the
2. lag phase.
3. log phase.
4. stationary phase.
5. death phase.
6. telophase.

1. The phase of the bacterial growth curve in which newly inoculated cells are adjusting to their new environment, metabolizing but not growing at an exponential rate, is the
2. lag phase.
3. log phase.
4. stationary phase.
5. death phase.
6. prophase.

1. The phase of the bacterial growth curve that shows the maximum rate of cell division is the
2. lag phase.
3. log phase.
4. stationary phase.
5. death phase.
6. prophase.

1. In the viable plate count method, a measured sample of a culture is evenly spread across an agar surface and incubated. Each _____ represents one _____ from the sample.
2. cell; cell
3. cell; colony
4. colony; cell
5. species; colony
6. generation; cell

1. When it is important to count the number of cells, determine cell size, and differentiate between dead and live cells, a/n ___ is used.
2. coulter counter
3. flow cytometer
4. SEM
5. methylene dye indicator
6. turbidity counter

True / False Questions

1. Phosphorus is one of the major elements needed in larger quantities by microorganisms.

1. Most microorganisms on earth can only live and survive in habitats that are similar to human body conditions.

1. Inorganic nitrogen must be converted to ammonia to be used by a cell.

1. Whether an organism is an autotroph or heterotroph depends on its source of nitrogen.

1. Whether an organism is a phototroph or a chemotroph depends on its source of energy.

1. Obligate saprobes can adapt to a living host.

1. A saprobe with a cell wall will utilize extracellular digestion.

1. Saprobes do not need a carbon source for growth and metabolism.

1. Lithoautotrophs use inorganic nutrients for carbon and energy sources.

1. Facilitated diffusion and active transport require a carrier protein to mediate the movement across the plasma membrane.

1. In a commensal relationship, the commensal benefits but the cohabitant is neither harmed nor benefited.

1. Anaerobes can be cultured in a CO2 environment.

1. The majority of microbes live and grow in habitats between pH 7 and 9.
2. Bacteria have an average generation time of 24 hours.

1. The time it takes for a freshly inoculated agar culture to develop visible colonies is primarily governed by the generation time of that species.

1. After binary fission, daughter cells will differ genetically.

1. A closed culture system is used to determine a population growth curve.

1. The degree of turbidity in a broth culture correlates to the amount of cell growth.

1. The direct cell count, using a cytometer, can calculate viable cell numbers from a sample without the use of dyes.

1. A Coulter counter can count viable cells as well as determine the size.

1. Bacterial biofilms stimulate the immune system differently than planktonic bacteria.

1. Planktonic bacteria are more susceptible to antibiotics as compared to biofilm microorganisms.

Multiple Choice Questions

1. This bacterium is photosynthetic, but without light it can use organic compounds to make energy. Its carbon source is a organic compound. The appropriate classification for this organisms would be:
2. photoheterotroph
3. photoautotroph
4. chemoautotroph
5. lithotroph

1. Which of the following environmental conditions would be inappropriate for isolation of extremophilic microorganisms?
2. mud, with 0% oxygen content
3. a yogurt container, pH 4.7
4. a compost pile with decaying vegatables and grass, temperature of 55 degree celsius
5. seawater, NaCl content of 3.5%

1. You want to experiment with microbial growth in various nutrients, so you inoculate a loopful of E. coli into a tube of honey. Which statement best describes what you expect to happen and why?
2. The bacterium grows incredibly well in the honey because fructose is such a great nutrient for bacteria.
3. The bacteria do not grow because they have been dehydrated by the honey.
4. The bacteria will not growth because the excessive sugar is directly toxic to the bacteria.
5. The bacteria do not growth because there is only sugar in the honey, without other nutrients present they cannot survive.

1. Which organism below has a problem in maintaining cellular electrolyte and fluid balance in its environment?
2. a protozoan in a fresh-water lake
3. a bacterium in a fresh-water lake
4. a bacterium in Great Salt Lake
5. all of the above have problems in maintaining electrolyte and fluid balance within the cell

1. What statement can one make about microbial growth within food in the refrigerator?
2. There is no growth of microorganisms in food in the refrigerator: the cold temperature kills or inactivates microbial cells.
3. The absence of light in this storage condition greatly reduces the growth of most microbial pathogens.
4. Most food does not have enough oxygen content for most microorganisms to thrive.
5. The growth of the microorganisms in the food depends on their optimal growth temperatures: some grow slow and others grow faster.

1. The milk that you bought from a grocery store a month ago got pushed to the back of the refrigerator hidden by other objects. Finding it a month later, unopened, you would like to now use it. Which statement is true?
2. The milk will still be fresh since it is a sterilized product.
3. Only thermoduric bacteria will be thriving in the milk.
4. The milk will still be fresh since the lactose sugar prevents the growth of any microorganisms.
5. The milk will be spoiled, making you realize you should be purchased raw milk for it would still be fresh since it contains no microorganisms.

1. A bacterium is inoculated into a tube of nutrient broth and incubated. After incubation, it appears turbid throughout, top to bottom, with the most amount of turbidty at the very top. This bacterium would be called a:
2. aerotolerant
3. microaerophile
4. obligate aerobe
5. facultative anaerobe
6. psychrotroph

1. You inoculate the bacterium into 3 tubes of nutrient broth medium containing salt–0.5% NaCl, 5% NaCl, and 15% NaCl. After incubation, you notice that the organism is growing very well in the 15%, and somewhat in the 5%. There is no growth in the third tube. This organism would be called:
2. haloduric
3. osmophobic
4. halophilic
5. barophilic

1. You have inoculated your Clostridium species into a tube of media. After incubation, you find that it is not growing and you then realize that this organism is an obligate anaerobe. What is the best explanation for this lack of growth?
2. Clostridium does not have enzymes to break down hydrogen peroxide.
3. There is not enough oxygen for use when hydrogen peroxide is present.
4. There is not enough water in the environment for Clostridium to grow.
5. Oxygen in the medium destroys the enzymes needed by Clostridium to undergo aerobic respiration.

1. After using the jelly on a sandwich, you close the jar and inadvertently place it on a room temperature shelf instead of in the refrigerator. When looking for the jelly a couple of weeks later and finding it on the shelf, you notice growth of a microorganism on the top of the jelly. What type of organism is likely to grow in this environment?
2. a bacterium
3. a protozoan
4. a fungus
5. a virus

1. What is the difference between mutualism and synergism?
2. In a synergistic relationship the organisms cannot survive without each other.
3. In a mutualistic relationship the organisms are dependant upon each other.
4. In a mututalistic relationship both organisms benefit, but in a synergistic relationship both organisms are harmed.
5. In a synergistic relationship both organisms benefit, but in a mutualistic relationship both organisms are harmed.

1. Which of the following statements is the best explanation of why communities of microorganisms in biofilms are synergistic.
2. The various microbial species in the biofilm interact with each other.
3. One microbial species may produce a metabolic end product that can be used as a substrate by another species.
4. The different microbial species can all grow together.
5. The various microbial species can change the environment to their growth advantage, allowing all to grow better.

1. The termite requires the protozoan Trichonympha in its gut to provide the enzyme cellulase for the termite’s use of cellulose in wood products. The protozoan uses the end products of the cellulose breakdown. This would be a _____ relationship.
2. commensualistic
3. mutualistic
4. parasitic
5. antagonistic

1. A loopful of bacteria containing 1000 bacterial cells is inoculated into a nutrient broth and incubated. The culture was in lag phase for 10 minutes and then went into exponential log phase growth for 5 hours. The generation time for the bacterium is 15 minutes. Which equation set up is the correct one to determine how many cells at the end of the 5 hours of log phase growth.
2. 1000 X 220
3. 1000 X 40
4. 1000 X 24
5. 1000 X 5 X 2 X 15

1. You have a tube of E. coli in nutrient broth that has been growing in a 37 degree C incubator. This culture is then inoculated into 3 tubes of media:

• Tube B is lactose broth, warmed to room temperature, inoculated, and then placed at 37oC.
• Tube C is nutrient broth taken right out of the refrigerator, inoculated, and then placed at 37oC.
• Tube D is nutrient broth, warmed to room temperature, inoculated, and then placed at 37oC.

The original tube of E. coli (called tube A) is placed back into the 37oC for incubation. In the next one-half hour, which culture will grow the fastest and why?

1. Tube A will grow fastest because it is the original culture and has already been growing.
2. Tube B will grow fastest because lactose is a good nutrient for all bacterial species.
3. Tube C will grow fastest because the medium has been stored cold, and is fresher than the other media used.
4. Tube D will grow fastest because the nutrients and the temperature are optimal for a fast lag phase.