Question 1

Colony morphology is defined as:

Accepted Answer

A)  Colony characteristics and form 
B)  Colony size and color 
C)  Colony smell and shape 
D)  Colony constitution and environmental conditions 
A)  Colony characteristics and form 
B)  Colony size and color 
C)  Colony smell and shape 
D)  Colony constitution and environmental conditions

Question 2

A technician is reading a sputum culture on the bench.There is growth on the BAP and CHOC plates,but no growth on the MAC plate.The colonies growing on the BAP have discolored the media to a green color around and under the colonies.What organism could this be?

Accepted Answer

A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Haemophilus influenzae 
D)  Streptococcus pneumoniae 
A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Haemophilus influenzae 
D)  Streptococcus pneumoniae

Question 3

A technician is reading the plates from a sputum culture.The culture is from a patient with cystic fibrosis.One organism dominates the blood agar,chocolate,and MacConkey plates.The MacConkey plate shows an organism with a green pigment and a metallic sheen.The probable identification for this organism is:

Accepted Answer

A)  Pseudomonas aeruginosa 
B)  Serratia marcescens 
C)  Chromobacterium violaceum 
D)  Prevotella melaninogenica 
A)  Pseudomonas aeruginosa 
B)  Serratia marcescens 
C)  Chromobacterium violaceum 
D)  Prevotella melaninogenica

Question 4

a-Hemolysis is:

Accepted Answer

A)  Complete clearing of erythrocytes in a blood agar plate around and under the colony 
B)  Partial lysing of erythrocytes in a blood agar plate around and under the colony 
C)  When organisms have no lytic effect on the erythrocytes in the blood agar plate 
D)  A pink "halo" around a colony 
A)  Complete clearing of erythrocytes in a blood agar plate around and under the colony 
B)  Partial lysing of erythrocytes in a blood agar plate around and under the colony 
C)  When organisms have no lytic effect on the erythrocytes in the blood agar plate 
D)  A pink "halo" around a colony

Question 5

When microbiologists encounter a sputum specimen,they know that the upper respiratory tract contains many indigenous organisms and to identify every organism in the culture would be a time-consuming,cost-prohibitive,and insurmountable task.So microbiologists must:

Accepted Answer

A)  Work quickly with commercially available kits to identify all organisms present in a sputum specimen for the best quality patient care available. 
B)  Work up only the gram-negative rods present in the culture. 
C)  Differentiate the potential pathogens from the "usual" inhabitants of the upper respiratory tract and direct the diagnostic workup only to potential pathogens. 
D)  Be able to ascertain whether the results generated by a commercial or automated system correlate with the suspected organism. 
A)  Work quickly with commercially available kits to identify all organisms present in a sputum specimen for the best quality patient care available. 
B)  Work up only the gram-negative rods present in the culture. 
C)  Differentiate the potential pathogens from the "usual" inhabitants of the upper respiratory tract and direct the diagnostic workup only to potential pathogens. 
D)  Be able to ascertain whether the results generated by a commercial or automated system correlate with the suspected organism.

Question 6

A technician is reading a vaginal culture on the bench.There is growth on the sheep blood agar (SBA)and chocolate (CHOC)plates,but no growth on the MacConkey (MAC)plate.The colonies growing on the SBA have produced a narrow,diffuse zone of b-hemolysis around and under the colonies.What organism could this be?

Accepted Answer

A)  Escherichia coli 
B)  Streptococcus agalactiae 
C)  Streptococcus pyogenes 
D)  Streptococcus pneumoniae 
A)  Escherichia coli 
B)  Streptococcus agalactiae 
C)  Streptococcus pyogenes 
D)  Streptococcus pneumoniae

Question 7

Colonies of Bacillus anthracis are described as:

Accepted Answer

A)  Curschmann's spiral 
B)  Mickey Mouse ears 
C)  Medusa's heads 
D)  Flower like 
A)  Curschmann's spiral 
B)  Mickey Mouse ears 
C)  Medusa's heads 
D)  Flower like

Question 8

All the following colors are commonly used to describe bacteria EXCEPT:

Accepted Answer

A)  Buff 
B)  White 
C)  Orange 
D)  Gray 
A)  Buff 
B)  White 
C)  Orange 
D)  Gray

Question 9

What organism forms a small,fuzzy-edged colony with an umbonate center on blood or chocolate agar?

Accepted Answer

A)  Eikenella corrodens 
B)  Staphylococcus aureus 
C)  Escherichia coli 
D)  Streptococcus pyogenes 
A)  Eikenella corrodens 
B)  Staphylococcus aureus 
C)  Escherichia coli 
D)  Streptococcus pyogenes

Question 10

Colonies of Staphylococcus aureus are usually described as:

Accepted Answer

A)  Opaque 
B)  Transparent 
C)  Translucent 
D)  Ground glass 
A)  Opaque 
B)  Transparent 
C)  Translucent 
D)  Ground glass

Question 11

This bacteria is said to have a fruity or grapelike smell.

Accepted Answer

A)  Staphylococcus aureus 
B)  Proteus mirabilis 
C)  Pseudomonas aeruginosa 
D)  Nocardia sp. 
A)  Staphylococcus aureus 
B)  Proteus mirabilis 
C)  Pseudomonas aeruginosa 
D)  Nocardia sp.

Question 12

All of the following characteristics are used to describe bacterial colony characteristics EXCEPT:

Accepted Answer

A)  Temperature 
B)  Hemolysis 
C)  Color 
D)  Elevation 
A)  Temperature 
B)  Hemolysis 
C)  Color 
D)  Elevation

Question 13

Swarming is:

Accepted Answer

A)  Many bacterial colonies crowded together at one place on the agar plate 
B)  When colonies on a blood agar plate have a "halo" around the bacterial colony 
C)  When a bacterial colony on a blood agar plate grows over the top of the erythrocytes it hemolyzed 
D)  A hazy blanket of growth on the surface of the agar that extends way beyond the streak lines 
A)  Many bacterial colonies crowded together at one place on the agar plate 
B)  When colonies on a blood agar plate have a "halo" around the bacterial colony 
C)  When a bacterial colony on a blood agar plate grows over the top of the erythrocytes it hemolyzed 
D)  A hazy blanket of growth on the surface of the agar that extends way beyond the streak lines

Question 14

A technician is reading stool culture plates.She is looking for enteric pathogens on the MacConkey (MAC)plate.What do they look like?

Accepted Answer

A)  Clear, colorless colonies 
B)  Large, bright pink colonies 
C)  Small, mucoid, green colonies 
D)  Small, orange colonies 
A)  Clear, colorless colonies 
B)  Large, bright pink colonies 
C)  Small, mucoid, green colonies 
D)  Small, orange colonies

Question 15

Streptococcus pneumoniae typically produces colonies that are said to resemble coins.The technical term for this colony shape is:

Accepted Answer

A)  Umbonate 
B)  Flat 
C)  Umbilicate 
D)  Raised 
A)  Umbonate 
B)  Flat 
C)  Umbilicate 
D)  Raised

Question 16

A technician is reading a sputum culture on the bench.There is growth on the sheep blood agar (SBA)and chocolate (CHOC)plates,but no growth on the MacConkey (MAC)plate.The colonies growing on the SBA have produced a wide,deep,clear zone of b-hemolysis around and under the colonies.What organism could this be?

Accepted Answer

A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Streptococcus pyogenes 
D)  Streptococcus pneumoniae 
A)  Escherichia coli 
B)  Staphylococcus aureus 
C)  Streptococcus pyogenes 
D)  Streptococcus pneumoniae

Question 17

The colonies of this organism form large,rough,greenish,hemolytic colonies on blood agar.What organism is it?

Accepted Answer

A)  Staphylococcus aureus 
B)  Escherichia coli 
C)  Streptococcus pyogenes 
D)  Bacillus cereus 
A)  Staphylococcus aureus 
B)  Escherichia coli 
C)  Streptococcus pyogenes 
D)  Bacillus cereus

Exam 8: Use of Colonial Morphology for the Presumptive Identification of Microorganisms

Colony morphology is defined as:

A technician is reading a sputum culture on the bench.There is growth on the BAP and CHOC plates,but no growth on the MAC plate.The colonies growing on the BAP have discolored the media to a green color around and under the colonies.What organism could this be?

a-Hemolysis is:

When microbiologists encounter a sputum specimen,they know that the upper respiratory tract contains many indigenous organisms and to identify every organism in the culture would be a time-consuming,cost-prohibitive,and insurmountable task.So microbiologists must:

Colonies of Bacillus anthracis are described as:

All the following colors are commonly used to describe bacteria EXCEPT:

What organism forms a small,fuzzy-edged colony with an umbonate center on blood or chocolate agar?

Colonies of Staphylococcus aureus are usually described as:

This bacteria is said to have a fruity or grapelike smell.

All of the following characteristics are used to describe bacterial colony characteristics EXCEPT:

Swarming is:

A technician is reading stool culture plates.She is looking for enteric pathogens on the MacConkey (MAC)plate.What do they look like?

Streptococcus pneumoniae typically produces colonies that are said to resemble coins.The technical term for this colony shape is:

The colonies of this organism form large,rough,greenish,hemolytic colonies on blood agar.What organism is it?

Bacterial Cell Structure, physiology, Metabolism, and Genetics

Host-Parasite Interaction

Laboratory Role in Infection Control

Control of Microorganisms

Performance Improvement in the Microbiology Laboratory

Specimen Collection and Processing

Microscopic Examination of Infected Materials

Biochemical Identification of Gram-Negative Bacteria

Immunodiagnosis of Infectious Diseases

Applications of Molecular Diagnostics

Antibiotic Mechanisms of Action and Resistance

Antimicrobial Susceptibility Testing

Staphylococci

Streptococcus, enterococcus, and Other Catalase-Negative Gram-Positive Cocci

Aerobic Gram-Positive Bacilli

Neisseria Species and Moraxella Catarrhalis

Haemophilus and Other Fastidious Gram-Negative Bacilli

Enterobacteriaceae

Vibrio,aeromonas,plesiomonas and Campylobacter Species

Nonfermenting and Miscellaneous Gram-Negative Bacilli

Anaerobes of Clinical Importance

Spirochetes

Chlamydia and Rickettsia

Mycoplasma and Ureaplasma

Mycobacterium Tuberculosis and Other Nontuberculosis Mycobacteria

Medically Significant Fungi

Diagnostic Parasitology

Clinical Virology

Agents of Bioterror

Biofilms: Architects of Disease

Upper and Lower Respiratory Tract Infections

Skin and Soft Tissue Infections

Gastrointestinal Infections and Food Poisoning

Infections of the Central Nervous System

Bacteremia and Sepsis

Urinary Tract Infections

Genital Infections and Sexually Transmitted Diseases

Infections in Special Populations

Zoonotic Diseases

Ocular Infections

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