Test Bank For Textbook Of Diagnostic Microbiology
7th Edition By Connie R. Mahon
Chapters 1 - 41
, Mahon: Textbook of Diagnostic Microbiology, 7th Edition Test Bank
Table of contents
Part 1: Introduction to Clinical Microbiology
Chapter 1. Bacterial Cell Structure, Physiology, Metabolism, and Genetics
Chapter 2. Host-Parasite Interaction
Chapter 3. The Laboratory Role in Infection Control
Chapter 4. Control of Microorganisms: Disinfection, Sterilization, and Microbiology Safety
Chapter 5. Performance Improvement in the Microbiology Laboratory
Chapter 6. Specimen Collection and Processing
Chapter 7. Microscopic Examination of Materials from Infected Sites
Chapter 8. Use of Colony Morphology for the Presumptive Identification of Microorganisms
Chapter 9. Biochemical Identification of Gram-Negative Bacteria
Chapter 10. Immunodiagnosis of Infectious Diseases
Chapter 11. Applications of Molecular Diagnostics
Chapter 12. Antibacterial Mechanisms of Action and Bacterial Resistance Mechanisms
Chapter 13. Antimicrobial Susceptibility Testing
Part 2: Laboratory Identification of Significant Isolates
Chapter 14. Staphylococci
Chapter 15. Streptococcus, Enterococcus, and Other Catalase-Negative, Gram-Positive Cocci
Chapter 16. Aerobic Gram-Positive Bacilli
Chapter 17. Neisseria Species and Moraxella catarrhalis
Chapter 18. Haemophilus, HACEK, Legionella and Other Fastidious Gram-Negative Bacilli
Chapter 19. Enterobacteriaceae
Chapter 20. Vibrio, Aeromonas, and Campylobacter Species
Chapter 21. Nonfermenting and Miscellaneous Gram-Negative Bacilli
Chapter 22. Anaerobes of Clinical Importance
Chapter 23. The Spirochetes
Chapter 24. Chlamydia, Rickettsia, and Similar Organisms
Chapter 25. Mycoplasma and Ureaplasma
Chapter 26. Mycobacterium tuberculosis and Nontuberculous Mycobacteria
Chapter 27. Medically Significant Fungi
Chapter 28. Diagnostic Parasitology
Chapter 29. Clinical Virology
Chapter 30. Agents of Bioterror and Forensic Microbiology
Chapter 31. Biofilms: Architects of Disease
Part 3: Laboratory Diagnosis of Infectious Diseases: and Organ System Approach to Diagnostic
Microbiology
Chapter 32. Upper and Lower Respiratory Tract Infections
Chapter 33. Skin and Soft Tissue Infections
Chapter 34. Gastrointestinal Infections and Food Poisoning
Chapter 35. Infections of the Central Nervous System
Chapter 36. Bacteremia and Sepsis
Chapter 37. Urinary Tract Infections
Chapter 38. Genital Infections and Sexually Transmitted Infections
Chapter 39. Infections in Special Populations
Chapter 40. Zoonotic Diseases
Chapter 41. Ocular Infections
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,Chapter 01: Bacterial Cell Structure, Physiology, Metabolism, and Genetics
Mahon: Textbook of Diagnostic Microbiology, 7th Edition Test Bank
MULTIPLE CHOICE
1. To survive, microbial inhabitants have learned to adapt by varying all of the following, except
a. growth rate.
b. growth in all atmospheric conditions.
c. growth at particular temperatures.
d. bacterial shape.
ANSWER: D
The chapter begins by discussing the way microbial inhabitants have had to evolve to survive
in many different niches and habitats. It discusses slow growers, rapid growers, and
replication with scarce or abundant nutrients, under different atmospheric conditions,
temperature requirements, and cell structure. Bacterial shape as a form of evolution is not
discussed.
OBJ: Level 2: Interpretation
2. Who was considered the father of protozoology and bacteriology?
a. Anton van Leeuwenhoek
b. Louis Pasteur
c. Carl Landsteiner
d. Michael Douglas
ANSWER: A
The book discusses Anton van Leeuwenhoek as the inventor of the microscope and the first
person to see the “beasties.” So they dubbed him the father of protozoology and bacteriology.
The other three individuals were not discussed.
OBJ: Level 1: Recall
3. Prokaryotic cells have which of the following structures in their cytoplasm?
a. Golgi apparatus
b. Ribosomes
c. Mitochondria
d. Endoplasmic reticulum
ANSWER: B
All the structures listed are found in eukaryotic cells, but ribosomes are the only ones that
apply to prokaryotic cells.
OBJ: Level 1: Recall
4. This form of DNA is commonly found in eukaryotic cells.
a. Linear
b. Circular
c. Plasmid
d. Colloid
.
.
, ANSWER: A
Circular and plasmid DNA are usually found only in bacteria, not eukaryotic cells. Colloid is
a property of protein molecules and is not associated with nucleotides.
OBJ: Level 1: Recall
5. The nuclear membrane in prokaryotes is
a. missing.
b. impenetrable.
c. a classic membrane.
d. a lipid bilayer membrane.
ANSWER: A
Prokaryotic cells do not have any membrane-bound structures in the cytoplasm including a
structured nucleus.
OBJ: Level 1: Recall
6. A microorganism that is a unicellular organism and lacks a nuclear membrane and true
nucleus belongs to which classification?
a. Fungi
b. Bacteria
c. Algae
d. Parasite
ANSWER: B
Fungi, algae, and parasites are unicellular eukaryotic organisms that contain a true nucleus.
Bacteria are prokaryotic and do not contain a true nucleus or nuclear membrane.
OBJ: Level 1: Recall
7. In the laboratory, the clinical microbiologist is responsible for all the following, except
a. isolating microorganisms.
b. selecting treatment for patients.
c. identifying microorganisms.
d. analyzing bacteria that cause disease.
ANSWER: B
Clinical microbiologists do not select the treatment for patients. They provide the doctor with
the name of the organism and the antibiotics that can kill the bacteria, but not in the final
selection of treatment protocols.
OBJ: Level 2: Recall
8. What enables the microbiologist to select the correct media for primary culture and optimize
the chance of isolating a pathogenic organism?
a. Determining staining characteristics
b. Understanding the cell structure and biochemical pathways of an organism
c. Understanding the growth requirements of potential pathogens at specific body site
d. Knowing the differences in cell walls of particular bacteria
ANSWER: C
, By understanding growth requirements, a microbiologist can maximize the chance of the
organism being isolated from a culture. The other three choices are used to identify a
bacterium once it has grown on media.
OBJ: Level 2: Interpretation
9. A clinical laboratory scientist is working on the bench, reading plates, and notices that a
culture has both a unicellular form and a filamentous form. What type of organism exhibits
these forms?
a. Virus
b. Fungi
c. Bacteria
d. Parasite
ANSWER: B
Viruses typically only have one form and would not grow on plate media. Bacteria have two
forms: a vegetative cell and spore form. Parasites may have trophozoite, cysts, egg, etc. Fungi
are the organism classification that may have both unicellular yeast forms and filamentous
hyphal forms in the same culture plate.
OBJ: Level 2: Interpretation
10. All of the following statements are true about viruses, except:
a. Viruses consist of DNA or RNA but not both.
b. Viruses are acellular but are surrounded by a protein coat.
c. Viruses can infect bacteria, plants, and animals.
d. Viruses do not need host cells to survive and grow.
ANSWER: D
Viruses need to have a host cell because they do not have the ability to reproduce or nourish
themselves without the host’s cellular mechanisms.
OBJ: Level 2: Interpretation
11. Diagnostic microbiologists apply placement and naming of bacterial organisms into all the
following categories, except
a. order.
b. family.
c. genus.
d. species.
ANSWER: A
Clinical microbiologists use the family, genus, and species taxonomic categories to identify
species that are important for diagnostic diseases.
OBJ: Level 1: Recall
12. Bacterial species that exhibit phenotypic differences are considered
a. biovarieties.
b. serovarieties.
c. phagevarieties.
d. subspecies.
.
.
, ANSWER: D
Biovarieties vary based on biochemical test results, serovarieties vary based on serologic test
results, and phagevarieties is a fictitious word.
OBJ: Level 2: Interpretation
13. What structure is described as a phospholipid bilayer embedded with proteins and sterols that
regulates the type and amount of chemicals that pass in and out of a cell?
a. Cell wall
b. Mitochondria
c. Endoplasmic reticulum
d. Plasma membrane
ANSWER: D
The cell wall is the outer covering made up of lipids. The mitochondria is a cellular organelle
that is considered the powerhouse of the cell (electron transport and oxidative phosphorylation
occur here). The endoplasmic reticulum is a cellular organelle where protein synthesis occurs.
OBJ: Level 1: Recall
14. What makes the interior of the plasma membrane potentially impermeable to water-soluble
molecules?
a. The hydrophobic tails of the phospholipid molecules are found there.
b. The hydrophilic tails of the phospholipid molecules are found there.
c. The ion channels are found there.
d. The cholesterol molecules in the plasma membrane are found solely in the interior
of the membrane.
ANSWER: A
The plasma membrane is designed so that the hydrophilic heads of the phospholipid
molecules are positioned to make contact with the intracellular and extracellular fluids. The
hydrophobic tails of the phospholipid molecules face away from the fluids and form the
interior of the plasma membrane. The tails of the phospholipid molecules are hydrophobic,
not hydrophilic. The ion channels extend through the cellular membrane. The cholesterol
molecules also extend through the plasma membrane.
OBJ: Level 2: Interpretation
15. The function of a cell wall is to
a. regulate the transport of macromolecules in and out of the cell.
b. provide rigidity and strength to the exterior of the cell.
c. provide reserve energy to the eukaryotic cell.
d. protect the eukaryote from predators.
ANSWER: B
The plasma membrane regulates the transport of macromolecules in and out of the cell, not
the cell wall. The mitochondria provide energy to the eukaryotic cell. Cell walls are not able
to protect a eukaryotic cell from predators.
OBJ: Level 1: Recall
.
.
,16. Name the numerous short (3 to 10 μm) projections that extend from the cell surface and are
used for cellular locomotion.
a. Flagella
b. Mitochondria
c. Cilia
d. Phospholipid
ANSWER: C
By definition, cilia are short projections extending from the cell surface and are used for
locomotion, whereas flagella are longer projections used for locomotion. Mitochondria are
cellular organelles responsible for electron transport and oxidative phosphorylation.
Phospholipids are polar molecules that form the plasma membrane.
OBJ: Level 1: Recall
17. A microbiology technologist performs a traditional bacterial stain on a colony from a wound
culture that is suspected to contain bacteria from the genus Clostridium. The unstained areas
in the bacterial cell observed by the technologist are called
a. cilia.
b. ribosomes.
c. endospores.
d. mitochondria.
ANSWER: C
Ribosomes are small circular areas used for protein synthesis that are not visible on a
traditional stain. Cilia are short projections on the outside of the plasma membrane used for
locomotion. Mitochondria are cellular organelles used for energy production.
OBJ: Level 2: Interpretation
18. This constituent of a gram-positive cell wall absorbs crystal violet but is not dissolved by
alcohol, thus giving the gram-positive cell its characteristic purple color.
a. Mycolic acid
b. Cholesterol
c. Carbolfuchsin
d. Peptidoglycan
ANSWER: D
Mycolic acid is part of the cell wall of the Mycobacterium and Nocardia spp., but does not
play a part in the Gram stain. Cholesterol is also part of the cell membrane, not the cell wall,
so it does not play a part in the Gram stain. Carbolfuchsin is a stain used in bacteriology.
OBJ: Level 2: Interpretation
19. Mycobacteria have a gram-positive cell wall structure with a waxy layer containing these two
compounds.
a. Glycolipids and mycolic acid
b. Glycolipids and phospholipids
c. Mycolic acid and lipopolysaccharides
d. Lipopolysaccharides and phospholipids
ANSWER: A
, Glycolipids are a part of the waxy layer, but phospholipids are part of the plasma membrane.
Mycolic acid is a part of the waxy layer, but lipopolysaccharides are part of a gram-negative
cell wall. Lipopolysaccharides are part of a gram-negative wall, and phospholipids are part of
a plasma membrane.
OBJ: Level 1: Recall
20. When performing a Gram stain on a gram-negative organism, the crystal violet is absorbed
into this outer cell wall layer, and then washed away with the acetone alcohol. What is the
main component of the outer layer of the cell wall?
a. Peptidoglycan
b. Mycolic acid
c. N-acetyl-D-muramic acid
d. Lipopolysaccharide
ANSWER: D
Peptidoglycan is a thinner layer under the lipopolysaccharide in a gram-negative organism,
whereas mycolic acid is the waxy layer present in a mycobacterium’s outer cell wall, and
N-acetyl-D-muramic acid is part of the peptidoglycan.
OBJ: Level 1: Recall
21. The three regions of the lipopolysaccharide include all the following, except
a. antigenic O-specific polysaccharide.
b. mycolic acid.
c. core polysaccharide.
d. endotoxin (inner lipid A).
ANSWER: B
Antigenic O-specific polysaccharide, core polysaccharide, and endotoxin are all part of the
lipopolysaccharide layer.
OBJ: Level 1: Recall
22. The outer cell wall of the gram-negative bacteria serves three important functions, which
includes all the following, except:
a. It provides an attachment site for the flagella, which will act in locomotion.
b. It acts as a barrier to hydrophobic compounds and harmful substances.
c. It acts as a sieve.
d. It provides attachment sites that enhance adhesion to host cells.
ANSWER: A
The outer cell wall of gram-negative bacteria acts as a barrier to hydrophobic compounds and
harmful substances, acts as a sieve, and provides attachment sites that enhance adhesion to
host cells. Flagella attach to the cell membrane, not to the cell wall.
OBJ: Level 1: Recall
23. Mycoplasma and Ureaplasma spp. must have media supplemented with serum or sugar as
nutrients and because
a. their cell walls contain only peptidoglycan.
b. they lack cell walls.
.
.
, c. the sterols in their cell walls are soluble in normal bacterial media.
d. their cell walls contain detoxifying enzymes.
ANSWER: B
These two genera have no cell walls, so the other choices are not appropriate. Serum and
sugar are needed nutrients and assist with osmotic balance of the media.
OBJ: Level 1: Recall
24. What is the purpose of a capsule?
a. Prevent osmotic rupture of the cell membrane
b. Make up the periplasmic space
c. Act as a virulence factor in helping the pathogen evade phagocytosis
d. Provide an attachment site for somatic antigens
ANSWER: C
The capsule acts as a virulence factor in helping the pathogen evade phagocytosis because
antibodies have difficulty attaching to the capsule of bacteria and therefore are unable to
prepare the organism for ingestion. The cell membrane is not prone to osmotic rupture when
inside a host; the periplasmic space is found between the peptidoglycan and the
lipopolysaccharide layers of the cell wall in gram-negative organisms; and somatic antigens
are found below the capsule.
OBJ: Level 1: Recall
25. The three basic shapes of bacteria include all the following, except
a. spirochetes.
b. cell wall deficient.
c. cocci.
d. bacilli.
ANSWER: B
Cell wall deficient is not one of the basic shapes of bacteria. It refers to the cell wall
composition, not the bacterial shape.
OBJ: Level 1: Recall
26. The Gram stain is a routine stain used in bacteriology to determine gram-positive and
gram-negative bacteria based on the
a. phenotypic characteristics of the organism.
b. composition of the bacterial cell wall.
c. composition of the bacterial cell membrane.
d. composition of the bacterial pili.
ANSWER: B
The composition of the bacterial cell wall is routinely used in bacteriology. The peptidoglycan
cell walls of the gram-positive bacteria retain the crystal violet (purple) stain, whereas crystal
violet stain is washed away because of the lipopolysaccharide (outer membrane) present in the
cell walls of the gram-negative cells. The outer membrane retains the Safranin (pink) with the
counter stain.
OBJ: Level 1: Recall
, 27. In what staining procedure does carbolfuchsin penetrate the bacterial cell wall through heat or
detergent treatment?
a. Gram stain
b. Acridine orange stain
c. Endospore stain
d. Acid-fast stain
ANSWER: D
Of all the stains listed, the acid-fast stain is the only one that requires heating or detergent
treatment so that the carbolfuchsin stain can penetrate the waxy wall of acid-fast bacteria.
Gram staining uses crystal violet stain; acridine orange is used in acridine orange stain; and
the endospore stain uses malachite green.
OBJ: Level 1: Recall
28. What stain is used for medically important fungi?
a. Methylene blue
b. Acridine orange
c. Acid-fast
d. Lactophenol cotton blue
ANSWER: D
Lactophenol cotton blue is the only fungi stain listed. Methylene blue is used to stain
Corynebacterium spp.; acridine orange is used to stain all types of bacteria, living or dead;
and acid-fast is used to stain Mycobacterium spp.
OBJ: Level 1: Recall
29. All the following are types of media, except
a. selective.
b. differential.
c. fastidious.
d. transport.
ANSWER: C
Fastidious refers to the nutrient requirements of bacteria, not a type of media. Selective media
have ingredients added to grow only selected bacteria. Differential media have chemicals
added to allow visualization of metabolic differences of bacteria. Transport media are used to
keep bacteria alive during transport to the laboratory.
OBJ: Level 1: Recall
30. Which of the following environmental factors influence the growth of bacteria in the
laboratory?
a. pH
b. Temperature
c. Gaseous composition of the atmosphere
d. All of the above
ANSWER: D
.
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