Question 1

Which of the following statements is true concerning dark-field microscopy?

Accepted Answer

A) This type of microscopy is used in some laboratories to detect spirochetes. 
B) The condenser does not allow light to pass directly through the specimen but directs the light to hit the specimen at an oblique angle. 
C) This technique involves the alteration of microscopic technique rather than the use of dyes or stains to achieve contrast. 
D) All of the above are correct. 
A) This type of microscopy is used in some laboratories to detect spirochetes. 
B) The condenser does not allow light to pass directly through the specimen but directs the light to hit the specimen at an oblique angle. 
C) This technique involves the alteration of microscopic technique rather than the use of dyes or stains to achieve contrast. 
D) All of the above are correct. D

Question 2

The second step in the Gram stain is the application of the

Accepted Answer

A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer 
A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer C

Question 3

The third step in the Gram stain is the application of the

Accepted Answer

A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer. 
A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer. D

Question 4

Magnifications in excess of 100,000´ are achieved by which type of microscopy?

Accepted Answer

A) Bright-field microscopy 
B) Electron microscopy 
C) Dark-field microscopy 
D) Phase contrast microscopy 
E) All of the above are correct. 
A) Bright-field microscopy 
B) Electron microscopy 
C) Dark-field microscopy 
D) Phase contrast microscopy 
E) All of the above are correct.

Question 5

In microscopy, resolution can be defined as

Accepted Answer

A) the magnification power. 
B) the extent to which detail in the magnified object is maintained. 
C) the ability of objects to stand out from the background. 
D) All of the above are correct. 
A) the magnification power. 
B) the extent to which detail in the magnified object is maintained. 
C) the ability of objects to stand out from the background. 
D) All of the above are correct.

Question 6

The first step in the Gram stain is the application of the primary stain

Accepted Answer

A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer. 
A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer.

Question 7

After which step in the Gram stain are gram-positive bacteria FIRST distinguished from gram-negative?

Accepted Answer

A) Crystal violet 
B) Iodine mordant 
C) Gram's decolorizer 
D) Safranin 
A) Crystal violet 
B) Iodine mordant 
C) Gram's decolorizer 
D) Safranin

Question 8

Contrast in microscopy is most commonly achieved by

Accepted Answer

A) changing objectives for various specimens. 
B) increasing the resolution or resolving power. 
C) staining techniques. 
D) adding a blue filter to the light path. 
A) changing objectives for various specimens. 
B) increasing the resolution or resolving power. 
C) staining techniques. 
D) adding a blue filter to the light path.

Question 9

A mordant that is applied after the primary stain to chemically bond the alkaline dye to the bacterial cell wall is

Accepted Answer

A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer. 
A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer.

Question 10

The fourth step in the Gram stain is the application of the

Accepted Answer

A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer. 
A) safranin. 
B) crystal violet. 
C) Gram's iodine. 
D) Gram's decolorizer.

Question 11

The fluorochrome stain that can be used to detect mycobacteria is

Accepted Answer

A) calcofluor white. 
B) acridine orange. 
C) auramine. 
D) immunofluorescence. 
A) calcofluor white. 
B) acridine orange. 
C) auramine. 
D) immunofluorescence.

Question 12

Of the different types of staining and microscopy techniques, which is basically the most sensitive?

Accepted Answer

A) Chromogenic 
B) Fluorescent 
C) Phase contrast 
D) Light field 
A) Chromogenic 
B) Fluorescent 
C) Phase contrast 
D) Light field

Question 13

In the Kinyoun acid-fast staining method, ___________ replaces __________ in the primary stain solution.

Accepted Answer

A) increased phenol; heat 
B) heat; increased phenol 
C) mycolic acid; heat 
D) carbolfuchsin; phenol 
A) increased phenol; heat 
B) heat; increased phenol 
C) mycolic acid; heat 
D) carbolfuchsin; phenol

Question 14

The fluorochrome stain that can be used to study fungus is

Accepted Answer

A) calcofluor white. 
B) acridine orange. 
C) auramine. 
D) immunofluorescence. 
A) calcofluor white. 
B) acridine orange. 
C) auramine. 
D) immunofluorescence.

Question 15

The acid-fast stain is specifically designed for bacteria whose cell walls contain

Accepted Answer

A) teichoic acids. 
B) mycolic acids. 
C) peptidoglycan. 
D) disaccharide-pentapeptide subunits. 
A) teichoic acids. 
B) mycolic acids. 
C) peptidoglycan. 
D) disaccharide-pentapeptide subunits.

Exam 6: Role of Microscopy

Which of the following statements is true concerning dark-field microscopy?

The second step in the Gram stain is the application of the

The third step in the Gram stain is the application of the

Magnifications in excess of 100,000´ are achieved by which type of microscopy?

In microscopy, resolution can be defined as

The first step in the Gram stain is the application of the primary stain

After which step in the Gram stain are gram-positive bacteria FIRST distinguished from gram-negative?

Contrast in microscopy is most commonly achieved by

A mordant that is applied after the primary stain to chemically bond the alkaline dye to the bacterial cell wall is

The fourth step in the Gram stain is the application of the

The fluorochrome stain that can be used to detect mycobacteria is

Of the different types of staining and microscopy techniques, which is basically the most sensitive?

In the Kinyoun acid-fast staining method, ___________ replaces __________ in the primary stain solution.

The fluorochrome stain that can be used to study fungus is

The acid-fast stain is specifically designed for bacteria whose cell walls contain

Microbial Taxonomy

Bacterial Genetics Metabolism and Structure

Host-Microorganism Interactions

Laboratory Safety

Specimen Management

Traditional Cultivation and Identification

Nucleic Acid-Based Analytic Methods for Microbial Identification and Characterization

Immunochemical Methods Used for Organism Detection

Serologic Diagnosis of Infectious Diseases

Principles of Antimicrobial Action Resistance

Laboratory Methods and Strategies for Antimicrobial Susceptibility Testing

Staphylococcus, Micrococcus, and Similar Organisms

Streptococcus, Enterococcus, and Similar Organisms

Bacillus and Similar Organisms

Listeria, Corynebacterium, and Similar Organisms

Erysipelothirix, Lactobacillus, and Similar Organisms

Nocardia, Streptomyces, Rhodococcus, Oerskovia, and Similar Organisms

Enterobacteriaceae

Acinetobacter, Stenotrophomonas, and Other Organisms

Pseudomonas, Burkholderia, and Similar Organisms

Achromobacter, Rhizobium, Ochrobactrum, and Similar Organisms

Chryseobacterium, Sphingobacterium, and Similar Organisms

Alcaligenes, Bordetella Nonpertussis, Comamonas, and Similar Organisms

Vibrio, Aeromonas, Plesiomonas Shigelloides, and Chromobacterium Violaceum

Sphingomonas Paucimobilis and Similar Organisms

Moraxella

Eikenella Corrodens and Similar Organisms

Pasteurella and Similar Organisms

Actinobacillus, Kingella, Cardiobacterium, Capnocytophaga, and Similar Organisms

Haemophilus

Bartonella and Afipia

Campylobacter, Arcobacter, and Helicobacter

Legionella

Brucella

Bordetella Pertussis and Bordetella Parapertussis

Francisella

Streptobacillus Moniliformis and Spirillum Minus

Neisseria and Moraxella Catarrhalis

Overview and General Considerations

Laboratory Considerations

Mycobacteria

Obligate Intracellular and Nonculturable Bacterial Agents

Cell Wall-Deficient Bacteria: Mycoplasma and Ureaplasma

The Spirochetes

Laboratory Methods for Diagnosis of Parasitic Infections

Laboratory Methods in Basic Mycology

Laboratory Methods in Basic Virology

Bloodstream Infections

Infections of the Lower Respiratory Tract

Upper Respiratory Tract Infections and Other Infections of the Oral Cavity and Neck

Meningitis and Other Infections of the Central Nervous Systems

Infections of the Eyes, Ears, and Sinuses

Infections of the Urinary Tract

Genital Tract Infections

Gastrointestinal Tract Infections

Skin, Soft Tissue, and Wound Infections

Normally Sterile Body Fluids, Bone and Bone Marrow, and Solid Tissues

Laboratory Physical Design, Management, and Organization

Quality in the Clinical Microbiology Laboratory

Infection Control

Sentinel Laboratory Response to Bioterrorism New

Filters

In the Kinyoun acid-fast staining method, _ replaces in the primary stain solution.