Practice Questions Flashcards
(158 cards)
1
Q
1) Which of the following bacterial cell structures plays an important role in the creation of biofilms? A) glycocalyces B) flagella C) fimbriae D) pili E) both fimbriae and glycocalyces
A
E) both fimbriae and glycocalyces
2
Q
2) Short, hairlike structures used only by eukaryotic cells for movement are called A) pili B) flagella C) fimbriae D) pseudopodia E) cilia
A
E) Cilia
3
Q
3) Which of the following statements concerning osmosis is FALSE?
A) Osmosis requires a selectively permeable membrane.
B) During osmosis, water crosses to the side of the membrane with a lower solute concentration.
C) Cells placed in hypotonic solutions will gain water.
D) Cell shrinkage results when cells are placed in a hypertonic solution.
E) Osmosis stops when the system reaches equilibrium.
A
B) During osmosis, water crosses to the side of the membrane with a lower solute concentration.
4
Q
4)
The cells illustrated in Figure above are in a(n) \_\_\_\_\_\_\_\_ environment. A) hypotonic B) hypertonic C) isotonic D) fluid mosaic E) passive
A
A) hypotonic
5
Q
5) Which of the following is NOT true of prokaryotes?
A) Lack nucleus
B) Lack various internal structures bound with phospholipid membranes
C) Are typically 1.0 µm in diameter or smaller
D) Have a simple structure
E) Have 80S ribosomes
A
E) 80s ribosomes
6
Q
6) Eukaryotic ribosomes are composed of 50S and 30S subunits.
a) True
b) False
A
false
7
Q
7) Lysosomes result from the endocytosis of food particles by eukaryotic cells.
a) True
b) False
A
false
8
Q
8) Formation of a biofilm may contribute to bacteria’s ability to cause disease.
a) True
b) False
A
true
9
Q
9) In a(n) ——— solution, an animal cell can gain so much water that it may burst.
A) hypertonic
B) isotonic
C) hypotonic
A
hypotonic
10
Q
10) Lipid ——– is a part of the Gram-negative cell outer membrane that can produce fever, inflammation, and shock when it is released into the bloodstream.
A) LPS
B) NAM
C) A
D) NAG
A
A
11
Q
11) A ——– is a type of glycocalyx that is firmly attached to the cell.
A) capsule
B) slime layer
C) matrix
A
capsule
12
Q
12) Which of the following is true of metabolic processes:
A) Metabolism requires energy from light or catabolism of nutrients
B) Energy is stored in adenosine triphosphate (ATP)
C) Cells catabolize nutrients to form precursor metabolites
D) Precursor metabolites, energy from ATP, and enzymes are used in anabolic reactions
E) All of the above
A
All of the above
13
Q
13) Sulfanilamide is an antimicrobial drug that mimics the shape of an important substrate for a particular bacterial enzyme, thereby inhibiting the enzyme. This type of inhibition is known as A) allosteric inhibition. B) competitive inhibition. C) excitatory allosteric control. D) noncompetitive inhibition. E) feedback inhibition.
A
competitive inhibition
14
Q
14) A cell that uses an organic carbon source and obtains energy from light would be called a A) photoheterotroph. B) lithoautotroph. C) photoautotroph. D) chemoheterotroph. E) chemoautotroph.
A
photoheterotroph
15
Q
15) A(n) \_\_\_\_\_\_\_\_ organism require(s) oxygen for growth. A) anaerobic B) facultative anaerobic C) aerotolerant D) obligate aerobic E) aerotolerant and an anaerobic
A
d) obligate aerobic
16
Q
16) An organism that produces catalase enzyme is protected from the harmful effects of A) singlet oxygen. B) hydroxyl radical. C) peroxide anion. D) superoxide radical. E) molecular oxygen.
A
peroxide anion
17
Q
17) In the process of \_\_\_\_\_\_\_\_ microbes detect the presence and density of other microbes and modify their metabolic activity in response. A) quorum sensing B) antagonism C) mutualism D) symbiosis E) synergy
A
quorum sensing
18
Q
18) Organisms that can grow with or without oxygen present are
A) obligate aerobes.
B) facultative anaerobes.
C) aerotolerant anaerobes.
D) obligate anaerobes.
E) either facultative anaerobes or aerotolerant anaerobes.
A
either facultative anaerobes or aerotolerant anaerobes
19
Q
19) A microbiologist inoculates a growth medium with 100 bacterial cells/ml. If the generation time of the species is 1 hour, and there is no lag phase, how long will it be before the culture contains more than 10,000 cells/ml? A) 24 hours B) 7 hours C) 2 hours D) 3 hours E) 10 hours
A
7 hours
20
Q
20) A means of reproduction in which duplicate DNA molecules are separated by cell elongation, followed by formation of a septum to divide the cytoplasm is called A) budding. B) mitosis. C) logarithmic growth. D) cell division. E) binary fission.
A
binary fission
21
Q
21) The \_\_\_\_\_\_\_\_ of a population is the time it takes for the cells to double in number. A) binary fission B) exponential growth C) generation time D) arithmetic growth E) log phase
A
generation time
22
Q
22) \_\_\_\_\_\_\_\_ are complex communities of various types of microbes that adhere to surfaces. A) Aggregates B) Colonies C) Isolates D) Biofilms E) Media
A
biofilms
23
Q
right sequence:
The correct sequence for the phases indicated by the letters A, B, C and D is
A) death phase, log phase stationary phase, lag phase.
B) log phase, stationary phase, lag phase, death phase.
C) stationary phase, lag phase, log phase, death phase.
D) lag phase, log phase, stationary phase, death phase.
E) death phase, stationary phase, log phase, lag phase.
A
D) lag phase, log phase, stationary phase, death phase.
24
Q
24) When cells are metabolically active but not dividing, they are in the \_\_\_\_\_\_\_\_ phase. A) stationary B) log C) lag D) death E) exponential
A
lag
25
```
25) Metabolic activity is at maximum level in the ________ phase of growth.
A) lag
B) log
C) death
D) stationary
E) intermediate
```
log
26
```
26) A laboratory protocol lists the following ingredients: 1 g sucrose, 16.4 g Na2HPO4, 1.5 g (NH4)3PO4, 0.02 g CaCO3, KNO3, water to 1 liter and autoclave. This recipe is for a ________ medium.
A) defined agar
B) defined broth
C) complex broth
D) reducing agar
E) complex enrichment broth
```
defined broth
27
```
27) Microaerophiles are microbes that grow best at low
A) carbon dioxide levels.
B) pH values.
C) hydrostatic pressure
D) oxygen levels.
E) salt concentrations
```
oxygen levels
28
28) Organisms that require organic sources of carbon and energy are called ------.
A) chemoheterotrophs
B) chemoautotrophs
C) auxotrophs
chemoheterotrophs
29
29) A(n) -------- is a sample of microorganisms introduced into a growth medium.
A) culture
B) specimen
C) inoculum
inoculum
30
30) A pure culture is composed of cells that arise from a single -----.
A) cell
B) inoculum
C) sample
cell
31
```
31) Which of the following infectious agents is least resistant to destruction by chemical methods?
A) enveloped viruses
B) bacterial endospores
C) nonenveloped viruses
D) fungal spores
E) vegetative bacterial cells
```
enveloped viruses
32
```
32) Aseptic means
A) sterile.
B) free of all microbes.
C) clean.
D) sanitized.
E) free of pathogens.
```
free of pathogens
33
33) The dairy creamer used in restaurants is usually treated by
A) filtration.
B) ionizing radiation.
C) lyophilization.
D) ultra-high-temperature pasteurization.
E) autoclaving.
ultra high temp pasteurization
34
34) No chemical or antimicrobial agents inactivate prions.
A) True
B) False
False
35
35) Slow freezing is more damaging to microbial cells than quick freezing.
A) True
B) False
true
36
36) The process of freeze-drying microbes to preserve them is -----.
A) lyophilization
B) dessication
lyophilization
37
37) The amount of time needed to sterilize materials using moist heat is ---- than the time needed to sterilize using dry heat.
A) more
B) less
less
38
38) The ----- are the infectious agents most resistant to antimicrobial agents or processes.
A) endospores
B) cysts
C) prions
prions
39
39) The effectiveness of sterilization procedures is evaluated using ----- because of their resilience.
A) prions
B) cysts
C) endospores
endospores
40
```
40) A lipid membrane is present in which of the following?
A) naked viruses
B) enveloped viruses
C) prions
D) viroids
E) both prions and viroids
```
enveloped viruses
41
41) An antimicrobial that inhibits cell wall synthesis will result in which of the following?
A) Cells become more susceptible to osmotic pressure.
B) Cells cannot attach to their hosts.
C) Ribosomes lose their function.
D) The sterols in the cell wall become nonfunctional.
E) The replication of cells, including cancer cells, slows down.
cells become more susceptible to osmotic pressure
42
```
42) Beta-lactam antibiotics have an effect on which of the following types of cells?
A) animal cells
B) bacterial cells
C) fungal cells
D) virus-infected cells
E) both animal and fungal cells
```
bacterial cells
43
43) Which of the following is a target of drugs that inhibit protein synthesis?
A) the shape of the 30S ribosomal subunit
C) the enzymatic site of the 50S ribosomal subunit
D) movement of the ribosome from one codon to the next
E) the tRNA docking site
E) all of the above
all of the above
44
This figure represents a Petri plate. The gray area is where bacteria A is growing, the black area is where bacteria B is growing. The white area is a zone where neither organism is growing. What is the best interpretation of what is observed on the plate?
A) Bacteria B is producing an antibiotic that inhibits the growth of bacteria A.
B) Bacteria A produces a compound that inhibits the growth of bacteria B.
C) Bacteria A grows faster than bacteria B.
D) Bacterial colony B has depleted the nutrients in the area around the colony.
E) No conclusion can be made from this information.
A) Bacteria B is producing an antibiotic that inhibits the growth of bacteria A.
45
45) Which of the following is not a mechanism of antimicrobial action
A) inhibiting the synthesis of the cell wall.
B) inhibiting protein synthesis.
C) inhibiting nucleic acid synthesis.
D) inhibiting metabolic pathways.
E) disrupting the nuclear membrane.
disrupting nuclear membrane
46
46) Which of the following statements is true of selective toxicity?
A) Selective toxicity takes advantage of structural differences between host and pathogen.
B) To be effective, an antimicrobial agent must be more toxic to the patient than the pathogen.
C) Selective toxicity takes advantage of metabolic differences between host and pathogen.
D) Antimicrobial agents must target structural differences between host and pathogen and be more toxic to the patient than the pathogen.
E) Selective toxicity takes advantage of structural and/or metabolic differences between host and pathogen.
E) Selective toxicity takes advantage of structural and/or metabolic differences between host and pathogen.
47
```
47) The tetracyclines interfere with
A) protein synthesis.
B) cell wall synthesis.
C) cell membrane component synthesis.
D) nucleic acid synthesis.
E) folic acid synthesis.
```
protein synthesis
48
48) Drug-resistant populations of microbes arise when
A) exposure to drugs selectively kills sensitive cells, allowing overgrowth of resistant cells.
B) exposure to drugs causes mutations that produce resistance.
C) resistant cells become numerous in a population due to their greater vigor.
D) the patient becomes immune to the drug.
E) synergy between medications occurs.
A) exposure to drugs selectively kills sensitive cells, allowing overgrowth of resistant cells.
49
49) Nucleic acid analog drugs act by inhibiting ribosome function.
A) True
B) False
false
50
50) Because all cells engage in protein synthesis, there are few antimicrobial drugs that selectively inhibit this process.
A) True
B) False
false
51
51) Any drug that acts against a disease is called a(n) ------- agent.
A) analog
B) antibiotic
C) chemotherapeutic
chemotherapeutic
52
52) Selective ------ means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.
A) toxicity
B) action
C) treatment
toxicity
53
53) Nucleotide or nucleoside -------- are antimicrobial agents that mimic the chemical structure of DNA building blocks.
A) analogs
B) antisense
C) acids
analogs
54
54) Competition between beneficial microbes and potential pathogens is called microbial --------.
A) synergy
B) antagonism
antagonism
55
```
1) Which of the following are phagocytic cells found in the epidermis?
A) neutrophils
B) natural killer lymphocytes
C) erythrocytes
D) dendritic cells
E) T cell lymphocytes
```
dendritic cells
56
```
2) Response to specific pathogens that can improve with subsequent exposure is
A) the first line of defense.
B) the second line of defense.
C) the third line of defense.
D) microbial antagonism.
E) innate immunity.
```
the third line of defense
57
```
3) Which of the following cells increase in number during a helminth infection?
A) basophils
B) macrophages
C) neutrophils
D) eosinophils
E) lymphocytes
```
eosinophils
58
4) Which of the following areas of the body have mucous membranes?
A) mouth
B) nasal cavity
C) urinary system
D) mouth and nasal cavity
E) mouth, nasal cavity, and urinary system
E) mouth, nasal cavity, and urinary system
59
5) Protection from infection known as species resistance is a result of
A) the lack of suitable environment in the body.
B) the absence of receptors required for microbial attachment.
C) the presence of phagocytes in the tissues.
D) the salty, acidic condition of normal skin.
E) both the absence of necessary receptors and lack of suitable environment in the body.
E) both the absence of necessary receptors and lack of suitable environment in the body.
60
```
6) Which of the following statements regarding the surface of the skin is false?
A) It has sebum as a coating.
B) It has normal microbiota.
C) It has goblet cells.
D) It is salty.
E) It is acidic.
```
it has goblet cells
61
7) Which of the following contributes to protecting the eyes from microbial invasion?
A) Tears contain lysozyme and salt.
B) A mucus layer traps and removes microbes.
C) Tears mechanically flush particles from the eyes.
D) Tears contain lysozyme and salt and mechanically flush particles from the eyes.
E) Tears and mucus combine to trap microbes and remove them.
D) Tears contain lysozyme and salt and mechanically flush particles from the eyes.
62
8) The complement cascade and its by-products contribute to
A) attracting phagocytes to sites of infection.
B) triggering inflammation.
C) triggering release of interferons.
D) triggering inflammation and release of interferons.
E) both triggering inflammation and attracting phagocytes to sites of infection.
E) both triggering inflammation and attracting phagocytes to sites of infection.
63
```
9) Which of the following leukocytes have granules in their cytoplasm that stain blue with methylene blue?
A) eosinophils
B) monocytes
C) lymphocytes
D) neutrophils
E) basophils
```
basophils
64
```
10) Which cell matures into a macrophage?
A) monocyte
B) lymphocyte
C) basophil
D) eosinophil
E) neutrophil
```
monocyte
65
11) Which of the following are among the activities of neutrophils?
A) formation of neutrophil extracellular traps
B) phagocytosis
C) enzyme production that leads to the formation of nitric oxide
D) formation of neutrophil extracellular traps and phagocytosis
E) formation of neutrophil extracellular traps, phagocytosis, and production of nitric oxide
E) formation of neutrophil extracellular traps, phagocytosis, and production of nitric oxide
66
12) Fever is beneficial during viral infection because the higher temperature
A) denatures viral proteins.
B) increases vasodilation, bringing more leukocytes to the site of infection.
C) results in virus being shed in sweat.
D) prevents viral infection of fibroblasts.
E) increases the effectiveness of interferons.
E) increases the effectiveness of interferons.
67
13) Which of the following characteristics is shared by the skin and mucous membranes?
A) They are both constantly shedding and replacing cells.
B) They both have cilia.
C) The outer layers are composed of dead cells.
D) Sebum may be present.
E) Lysozymes are always present.
A) They are both constantly shedding and replacing cells.
68
14) Opsonization is
A) the coating of a pathogen by complement to facilitate phagocytosis.
B) the sticking of monocytes to the wall of the blood vessels at the site of infection.
C) damage resulting in cell lysis.
D) nonspecific leukocyte secretion of toxins onto the surface of virally infected cells.
E) phagocyte receptors detecting PAMPs.
A) the coating of a pathogen by complement to facilitate phagocytosis.
69
15) Which of the following statements is true of eosinophils?
A) They are in intact skin, sebum, tears, etc.
B) They produce the coating of a pathogen by complement.
C) They secrete toxins onto the surface of helminth parasites.
D) They decline during allergic reaction.
E) They release antibodies in response to microbes.
secrete toxins on the surface of the helminth parasite
70
16) Antigens are
A) specific molecules, or parts of molecules, that the body recognizes as foreign.
B) proteins the body produces against invading substances.
C) cells that protect the body against invaders.
D) proteins on the surface of our cells to which pathogens attach.
E) enzymes secreted to destroy a pathogen's cell wall.
A) specific molecules, or parts of molecules, that the body recognizes as foreign.
71
```
17) Which of the following is an exogenous antigen?
A) a bacterium inside a cell
B) a virus inside a cell
C) a bacterium outside a cell
D) a noninfected human cell
E) none of the above
```
bacterium outside a cell
72
```
18) The white blood cells primarily responsible for adaptive immunity are
A) NK lymphocytes and neutrophils.
B) B lymphocytes and T lymphocytes.
C) macrophages and eosinophils.
D) macrophages and neutrophils.
E) neutrophils and dendritic cells.
```
B and T lymphocytes
73
```
19) The antibody immune response is attributed to the action of
A) monocytes.
B) T lymphocytes.
C) B lymphocytes.
D) neutrophils.
E) macrophages.
```
B lymphocytes
74
20) Which of the following statements about T lymphocytes is FALSE?
A) T lymphocytes produce antibody molecules.
B) T lymphocytes directly attack cells and produce the cell-mediated immune response.
C) T lymphocytes are called such because they mature in the thymus.
D) T lymphocytes have TCRs that recognize antigen only if it is bound to MHC.
E) There are three types of T lymphocytes.
T lymphocytes produce antibody molecules
75
What will be the direct result of the interaction shown in this figure? (This interaction is occurring in a lymph node.) CD4 and MCHII
A) activation of a cytotoxic T lymphocyte
B) activation of a helper T lymphocyte
C) clonal deletion of a T lymphocyte
D) activation of a B lymphocyte
E) clonal deletion of a B lymphocyte
activation of a helper T lymphocytes
76
```
22) Class II MHC are found on
A) the skin.
B) red blood cells.
C) cytoplasmic membranes of nucleated cells.
D) muscle.
E) antigen-presenting cells.
```
antigen-presenting cells
77
23) What type of immunity is produced by the body when a person contracts a disease?
A) innate immunity
B) naturally acquired passive immunity
C) artificially acquired active immunity
D) artificially acquired passive immunity
E) naturally acquired active immunity
naturally acquired active immunity
78
24) What is the result when a dendritic cell phagocytizes a microbe and processes it?
A) activation of the dendritic cell to become a plasma cell
B) display of epitope-MHC I complexes on the surface of the cell
C) suppression of the immune response to the microbe
D) display of microbial fragments with CD8 glycoproteins
E) display of microbial epitope-MHC II complexes on the cell surface
E) display of microbial epitope-MHC II complexes on the surface of the cell
79
1) Which of the following can grow in a Petri plate on a laboratory table?
a) An anaerobic bacterium
b) An aerobic bacterium
c) Viruses on an agar surface
d) All of the above
B) aerobic bacterium
80
2) “In the laboratory, sterile inoculating loop is moved across the agar surface in a culture dish, thinning a sample and isolating individual.” This statement describes which of the following?
a) Broth culture
b) Pour plate
c) Streak plate
d) Dilution plate
streak plate
81
3) Superoxide dismutase ___________.
a) Causes hydrogen peroxide to become toxic
b) Detoxifies superoxide radicals
c) Neutralizes singlet oxygen
d) Is missing in aerobes
B) detoxified superoxide radicals
82
4) The most reactive of the four toxic forms of oxygen is _________.
a) The hydroxyl radical
b) The peroxide anion
c) The superoxide radical
d) Singlet oxygen
a) the hydroxyl radical
83
5) Microaerophiles that grow best with a high concentration of carbon dioxide in addition to a low level of oxygen are called?
a) Aerotolerant
b) Capnophiles
c) Facultative anaerobes
d) Fastidious
b) capnophiles
84
6) Which of the following is not a growth factor for various microbes?
a) Cholesterol
b) Water
c) Vitamins
d) Heme
b) water
85
7) Organisms that preferentially may thrive in icy waters are described as _______.
a) Barophiles
b) Thermophiles
c) Mesophiles
d) Psychrophiles
psychrophiles
86
8) Barophiles ________.
a) Cannot cause disease in humans
b) Live at normal barometric pressure
c) Die if put under high pressure
d) Thrive in warm air
A) cannot cause disease in humans
87
9) Which of the following terms best describes an organism that cannot exist in the presence of oxygen?
a) Obligate aerobe
b) Facultative aerobe
c) Obligate anaerobe
d) Facultative anaerobe
C) obligate anaerobe
88
10) In a defined medium, ___________.
a) The exact chemical composition of the medium is known
b) Agar is available for microbial nutrition
c) Blood may be included
d) Organic chemicals are excluded
A) the exact chemical composition is known
89
11) Which of the following is most useful in representing population growth on a graph?
a) Logarithmic reproduction of the growth curve
b) A semilogarithmic graph using a log scale on the y-axis
c) An arithmetic graph of the lag phase followed by a logarithmic section for the log, stationary, and death phases
d) None of the above would best represent a population growth curve
B) semilogarithmic graph of the log scale on the y axis
90
12) Which of the following methods is best for counting fecal bacteria from a stream to determine the safety of the water for drinking?
a) Dry weight
b) Turbidity
c) Viable plate counts
d) Membrane filtration
D) membrane filtration
91
13) A Coulter counter is a(n) ________.
a) Statistical estimation using 15 dilution tubes and a table of numbers to estimate the number of bacteria per milliliter
b) Indirect method of counting microorganisms
c) Device that directly counts microbes as they pass through a tube in front of an electronic detector
d) Device that directly counts microbes that are differentially stained with fluorescent dyes
c) Device that directly counts microbes as they pass through a tube in front of an electronic detector
92
14) Lyophilization can be described as __________.
a) Freeze-drying
b) Deep-freezing
c) Refrigeration
d) Pickling
A) freeze-drying
93
15) Quorum sensing is _________.
a) The ability to respond to changes in population density
b) A characteristic allowing secretion of matrix
c) Dependent on direct contact among cells
d) Associated with colonies in broth culture
A) ability to respond to changes in population density
94
1) In practical terms in everyday use, which of the following statements provides the definition of sterilization?
a) Sterilization eliminates organisms and their spores or endospores
b) Sterilization eliminates harmful microorganisms and viruses
c) Sterilization eliminates prions
d) Sterilization eliminates hyperthermophiles
a) Sterilization eliminates organisms and their spores or endospores
95
2) Which of the following substances or processes kills microorganisms on laboratory surfaces?
a) Antiseptics
b) Disinfectants
c) Degermers
d) Pasteurization
B) disinfectant
96
3) Which of the following best describes the disinfecting of cafeteria plates?
a) Pasteurization
b) Antisepsis
c) Sterilization
d) Sanitation
D) sanitation
97
4) The microbial dealth rate is used to measure the efficiency of ________.
a) A detergent
b) An antiseptic
c) Sanitization techniques
d) All of the above
D) all of the above
98
5) Which of the following statements is true concerning the selection of an antimicrobial agent?
a) An ideal antimicrobial agent is stable during storage
b) An ideal antimicrobial agent is fast acting
c) Ideal microbial agents do not exist
d) All of the above are correct
D) all of the above
99
6) The endospores of which organism can be used as a biological indicator of sterilization?
a) Bacillus stearothermophilus
b) Salmonella enterica
c) Mycobacterium tuberculosis
d) Staphylococcus aureus
a) Bacillus stearothermophilus
100
7) A company that manufactures an antimicrobial cleaner for kitchen counters claims that its products is effective when used in a 50% water solution. By what means may a scientist best verify this statement?
a) Disk-diffusion test
b) Phenol coefficient
c) Filter paper test
d) In-use test
D) in use test
101
8) Which of the following items functions most like an autoclave?
a) A boiling pan
b) Incinerator
c) Microwave oven
d) Pressure cooker
D) pressure cooker
102
9) The preservation of beef jerky from microbial growth relies on which method of microbial control?
a) Filtration
b) Lyophilization
c) Desiccation
d) Radiation
C) desiccation
103
10) Which of the following types of radiation is more widely used as an antimicrobial technique?
a) Electron beams
b) Visible light waves
c) Radio waves
d) Microwaves
A) electron beams
104
11) Which of the following substances would most effectively inhibit anaerobes?
a) Phenol
b) Silver
c) Ethanol
d) Hydrogen peroxide
D) hydrogen peroxide
105
12) Which of the following adjectives best describes a surgical procedure that is free of microbial agents?
a) Disinfected
b) Sanitized
c) Degermed
d) Aseptic
D) aseptic
106
13) Biosafety level 3 includes ________.
a) Double sets of entry doors
b) Pressurized suits
c) Showers in entry way
d) All of the above
A) double sets of doors
107
14) A sample of E. coli has been subjected to heat for a specified time, and 90% of the cells have been destroyed. Which of the following terms best describes this event?
a) Thermal death point
b) Thermal death time
c) Decimal reduction time
d) None of the above
C) decimal reduction time
108
15) Which of the following substances is least toxic to humans?
a) Carbolic acid
b) Glutaraldehyde
c) Hydrogen peroxide
d) Formalin
C) hydrogen peroxide
109
16) Which of the following chemicals is active against bacterial endospores?
a) Copper ions
b) Ethylene oxide
c) Ethanol
d) Triclosan
B) ethylene oxide
110
17) Which of the following disinfectants acts against cell membranes?
a) Phenol
b) Peracetic acid
c) Silver nitrate
d) Glutaraldehyde
A) phenol
111
18) Which of the following disinfectants contains alcohol?
a) Iodophor
b) Quat
c) Formalin
d) Tincture of bromine
D) tincture of bromine
112
19) Which antimicrobial chemical has been used to sterilize spacecraft?
a) Phenol
b) Alcohol
c) Heavy metal
d) Ethylene oxide
D) ethylene oxide
113
20) Which class of surfactant is most soluble in water?
a) Quaternary ammonium
b) Alcohols
c) Soaps
d) Peracetic acids
A) quaternary ammonium
114
1) Diffusion and dilution tests that expose pathogens to antimicrobials are designed to determine ________.
a) The spectrum of action of a drug
b) Which drug is most effective against a specific pathogen
c) The amount of a drug to use against a particular pathogen
d) Both C and B
D) both c and b
115
2) In a Kirby-Bauer susceptibility test, the presence of a zone of inhibition around disks containing antimicrobial agents indicates_________.
a) That the microbe does not grow in the presence of agents
b) That the microbe grows well in the presences of agents
c) The smallest amount an agent that will inhibit the growth of the microbe
d) The minimum amount of an agent that kills the microbe in question
A) that the microbe does not grow in the presence of agents
116
3) The key to successful chemotherapy is ________.
a) Selective toxicity
b) A diffusion test
c) The minimum inhibitory concentration test
d) The spectrum of action
A) selective toxicity
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4) Which of the following statements is relevant in explaining why sulfonamides are effective?
a) Sulfonamides attach to sterol lipids in the pathogen, disrupt the membranes, and lyse the cells
b) Sulfonamides prevent incorporation of amino acids into polypeptide chains
c) Humans and microbes use PABA differently in their metabolism
d) Sulfonamides inhibit DNA replication in both pathogens and human cells
C) humans and microbes use PABA differently in their metabolism
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5) Cross resistance is _________.
a) The deactivation of an antimicrobial agent by a bacterial enzyme
b) Alteration of the resistant cells so that an antimicrobial agent cannot attach
c) The mutation of genes that affect the cytoplasmic membrane channels so that antimicrobial agents cannot cross into the cell’s interior
d) Resistance to one antimicrobial agent because of its similarity to another antimicrobial agent
D) resistance to one antimicrobial agent because of its similarity to another antimicrobial agent
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6) Multiple-drug-resistant microbes _________.
a) Are resistant to all antimicrobial agents
b) Respond to new antimicrobials by developing resistance
c) Frequently develop in hospitals
d) All of the above
C) frequently develop in hospitals
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7) Which of the following is most closely associated with a beta-lactam ring?
a) Penicillin
b) Vancomycin
c) Bacitracin
d) Isoniazid
A) penicillin
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8) Drugs that act against protein synthesis include _________.
a) Beta-lactams
b) Trimethoprim
c) Polymyxin
d) Aminoglycosides
D) aminoglycosides
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9) Which of the following is false concerning antiviral drugs?
a) Macrolide drugs block attachment sites on the host cell wall and prevent viruses from entering
b) Drugs that neutralize the acidity of phagolysosomes prevent viral uncoating
c) Nucleotide analogs can be used to stop microbial replication
d) Drugs containing protease inhibitors retard viral growth by blocking the production of essential viral proteins
a) Macrolide drugs block attachment sites on the host cell wall and prevent viruses from entering
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10) PABA is ___________.
a) A substrate used in the production of penicillin
b) A type of B-lactamases
c) Molecularly similar to cephalosporins
d) Used to synthesize folic acid
D) used to synthesize folic acid
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1) In which type of symbiosis do both members benefit from their interaction?
a) Mutualism
b) Parasitism
c) Commensalism
d) Pathogenesis
A) mutualism
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2) An axenic environment is one that __________.
a) Exists in the human mouth
b) Contains only one species
c) Exists in the human colon
d) Both A and C
B) contains only one species
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3) Which of the following is false concerning microbial contaminants?
a) Contaminants may become opportunistic pathogens
b) Most microbial contaminants will eventually cause harm
c) Contaminants may be a part of the transient microbiota
d) Contaminants may be introduced by a mosquito bite
b) Most microbial contaminants will eventually cause harm
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4) The most frequent portal of entry for pathogens is _________.
a) The respiratory tract
b) The skin
c) The conjunctiva
d) A cut or wound
A) respiratory tract
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5) The process by which microorganisms attach themselves to cells is ______
a) Infection
b) Contamination
c) Disease
d) Adhesion
D) adhesion
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6) Which of the following is the correct sequence of events in infectious diseases?
a) Incubation, prodromal period, illness, decline, convalescence
b) Incubation, decline, prodromal period, illness, convalescence
c) Prodromal period, incubation, illness, decline, convalescence
d) Convalescence, prodromal period, incubation, illness, decline
a) Incubation, prodromal period, illness, decline, convalescence
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7) Which of the following are most likely to cause disease?
a) Opportunistic pathogens on a weakened host
b) Pathogens lacking the enzyme kinase
c) Pathogens lacking the enzyme collagenase
d) Highly virulent organisms
D) highly virulent organisms
131
8) The nature of bacterial capsules ____________.
a) Causes widespread blood clotting
b) Allows phagocytes to readily engulf these bacteria
c) Affects the virulence of these bacteria
d) Has no effect on the virulence of bacteria
c) Affects the virulence of these bacteria
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9) When pathogenic bacterial cells lose the ability to make adhesions, they typically _________.
a) Become avirulent
b) Produce endotoxin
c) Absorb endotoxin
d) Increase in virulence
A) become avirulent
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10) A disease in which a pathogen remains inactive for a long period of time before becoming active is termed a?
a) Subacute disease
b) Acute disease
c) Chronic disease
d) Latent disease
D) latent disease
134
11) Which of the following statements is the best definition of a pandemic disease?
a) It normally occurs in a given geographic area
b) It is a disease that occurs more frequently than usual for a geographical area or group of people
c) It occurs infrequently at no predictable time scattered over a large area or population
d) It is an epidemic that occurs on more than one continent at the same time
d) It is an epidemic that occurs on more than one continent at the same time
135
12) Which of the following types of epidemiologist is most like a detective?
a) Descriptive epidemiologist
b) Analytical epidemiologist
c) Experimental epidemiologist
d) Reservoir epidemiologist
b) Analytical epidemiologist
136
13) Consider the following case. An animal was infected with a virus. A mosquito bit the animal, was contaminated with the virus, and proceeded to bite and infect a person. Which was the vector?
a) Animal
b) Virus
c) Mosquito
d) Person
C) mosquito
137
14) A patient contracted athlete’s foot after long-term use of a medication. His physician explained that malady was directed to the medication. Such infections are termed ___________.
a) Healthcare-associated infections
b) Exogenous infections
c) Iatrogenic infections
d) Endogenous infections
d) Endogenous infections
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15) Which of the following phrases describes a contagious disease?
a) A disease arising from fomites
b) A disease that is easily passed from host to host in aerosols
c) A disease that arises from opportunistic members of normal microbiome
d) Both A and B
b) A disease that is easily passed from host to host in aerosols
139
1) Phagocytes of the epidermis are called ___________.
a) Microglia
b) Goblet cells
c) Alveolar macrophages
d) Dendritic cells
D) dendritic cells
140
2) Mucus-secreting membranes are found in ___________.
a) The urinary system
b) The digestive cavity
c) The respiratory passages
d) All of the above
D) all of the above
141
3) The completement system involves __________.
a) The production of antigens and antibodies
b) Serum proteins involved in nonspecific defense
c) A set of genes that distinguish foreign cells from body cells
d) The elimination of undigested remnants of microorganisms
B) serum proteins involved in nonspecific defense
142
4) The alternative complement activation pathway involves ____________.
a) Factors B, D and P
b) The cleavage of C5 to form C9
c) Binding to mannose sugar
d) Recognition of antigens bound to specific antibodies
A) factors B, D, and P
143
5) Which of the complement fragments is inflammatory?
a) C3a
b) C4a
c) C5a
d) All of the above
D) all of the above
144
6) The type of interferon present late in an infection is ___________.
a) Alpha interferon
b) Beta interferon
c) Gamma interferon
d) Delta interferon
C) gamma interferon
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7) Interferons ___________.
a) Do not protect the cell that secretes them
b) Stimulate the activity of macrophages
c) Cause muscle aches, chills, and fever
d) All of the above
D) all of the above
146
8) Which of the following is not targeted by a toll-like receptor?
a) Lipid A
b) Eukaryotic flagellar protein
c) Single-stranded RNA
d) Lipoteichoic acid
B) eukaryotic flagellar protein
147
9) Toll-like receptors (TLRs) act to ___________.
a) Bind microbial proteins and polysaccharides
b) Induce phagocytosis
c) Cause phagocytic chemotaxis
d) Destroy microbial cells
A) bind microbial proteins and polysaccharides
148
which of the following bind iron?
a) Lactoferrin
b) Siderophores
c) Transferrin
d) All the above
D) all of the above
149
1) Antibodies Function to ….
a) Directly destroy foreign organ grafts
b) Mark invading organisms for destruction
c) Kill intracellular viruses
d) Directly promote cytokine synthesis
e) Stimulate t cell growth
B) mark invading organisms for destruction
150
2) MHC class 11 molecules bind to …. And trigger ….
a) Endogenous antigens; cytotoxic T cells
b) Exogenous antigens; cytotoxic t cells
c) Antibodies; B cells
d) Endogenous antigens; helper t cells
e) Exogenous antigens; helpers t cells
E) exogenous antibodies; helper t cells
151
3) Rejection of foreign skin graft is an example of……
a) Destruction of virus infected cells
b) Tolerance
c) Antibody mediated immunity
d) A secondary immune response
e) A cell mediated immune response
E) cell mediated immune response
152
4) An autoantigen is …
a) An antigen from normal microbiota
b) A normal body component
c) An artificial antigen
d) Any carbohydrate antigen
e) Nucleic acid
B) a normal body component
153
5) Among the key molecules that control cell mediated cytotoxicity are ….
a) Perforin
b) Immunoglobulins
c) Complement
d) Cytokines
e) Interferons
D) cytokines
154
6) Which of the following lymphocyte predominates in blood?
a) T cells
b) B cells
c) Plasma cells
d) Memory cells
e) All are about equally prevalent
A) t cells
155
7) The major class of immunoglobulin found on the surface of the walls of the intestine and airways in secretory ……
a) IgG
b) IgM
c) IgA
d) IgE
e) IgD
C) IgA
156
8) Which cell express MHC class 1 molecules in a patient?
a) Red blood cells
b) Antigen presenting cells only
c) Neutrophils only
d) All nucleated cells
e) Dendritic cells only
D) all nucleated cells
157
9) In which of the following site in the body can be cells be found?
a) Lymph nodes
b) Spleen
c) Red bone marrow
d) Intestinal wall
e) All of the above
E) all of the above
158
10) Tc cells recognize epitopes only when the latter are held by …
a) MHC proteins
b) B cells
c) Interleukin 2
d) Granzyme
A) MHC proteins
