Question 1

Ergot and aflatoxin are toxins sometimes found in grains contaminated with fungi.

Accepted Answer

A) True 
 B)False

Question 2

Twenty- five people developed symptoms of nausea, vomiting, and diarrhea three to six hours after attending a church picnic where they ate a ham and green bean casserole with cream sauce. The most likely cause of this case of food intoxication is

Accepted Answer

A)  cholera toxin. 
B)  staphylococcal enterotoxin. 
C)  botulinum toxin. 
D)  erythrogenic toxin. 
E)  aflatoxin. 
A)  cholera toxin. 
B)  staphylococcal enterotoxin. 
C)  botulinum toxin. 
D)  erythrogenic toxin. 
E)  aflatoxin.

Question 3

Table 15.2 $\begin{array} { | l | c | } 
\hline \text { Bacterium } & \text { ID } 50 \
\hline \text { E. coli O157:H7 } & 20 \
\hline \begin{array} { l } 
\text { Legionella } \
\text { pneumophila }
\end{array} & 1 \
\hline \text { Shigella } & 10 \
\hline \begin{array} { l } 
\text { Treponema } \
\text { pallicum }
\end{array} & 57 \
\hline
\end{array}$
-Which organism in Table 15.2 most easily causes an infection?

Accepted Answer

A)  Shigella 
B)  E. coli O157:H7 
C)  Treponema pallidum 
D)  Legionella pneumophila 
E)  The answer cannot be determined based on the information provided. 
A)  Shigella 
B)  E. coli O157:H7 
C)  Treponema pallidum 
D)  Legionella pneumophila 
E)  The answer cannot be determined based on the information provided.

Question 4

Nonpathogenic Vibrio cholerae can acquire the cholera toxin gene by

Accepted Answer

A)  conjugation. 
B)  infecting a pathogenic Vibrio cholerae. 
C)  transduction. 
D)  transformation. 
E)  phagocytosis. 
A)  conjugation. 
B)  infecting a pathogenic Vibrio cholerae. 
C)  transduction. 
D)  transformation. 
E)  phagocytosis.

Question 5

Which of the following mechanisms is used by gram- negative bacteria to cross the blood- brain barrier?

Accepted Answer

A)  inducing TNF 
B)  antigenic variation 
C)  producing fimbriae 
D)  producing toxins 
E)  inducing endocytosis 
A)  inducing TNF 
B)  antigenic variation 
C)  producing fimbriae 
D)  producing toxins 
E)  inducing endocytosis

Question 6

The IDS1U1B150S1U1B0is

Accepted Answer

A)  the dose that will kill 50 percent of the test population. 
B)  the dose that will cause an infection in some of the test population. 
C)  the dose that will kill some of the test population. 
D)  the dose that will cause an infection in 50 percent of the test population. 
E)  a measure of pathogenicity. 
A)  the dose that will kill 50 percent of the test population. 
B)  the dose that will cause an infection in some of the test population. 
C)  the dose that will kill some of the test population. 
D)  the dose that will cause an infection in 50 percent of the test population. 
E)  a measure of pathogenicity.

Question 7

\(\begin{array} { l | l | l } 
\text { Bacterium } & \text { Portal of Entry } & \text { ID50 } \
\hline \text { Stephylococcus aureus } & \text { Wound } & 50 for Staphylococcus aureus in wounds with and without the administration of ampicillin before surgery. Based on the data, the administration of ampicillin before surgery

Accepted Answer

A)  increases the risk of staphylococcal infection. 
B)  decreases the risk of staphylococcal infection. 
C)  replaces tetracycline. 
D)  has no effect on risk of infection. 
E)  The answer cannot be determined based on the information provided. 
A)  increases the risk of staphylococcal infection. 
B)  decreases the risk of staphylococcal infection. 
C)  replaces tetracycline. 
D)  has no effect on risk of infection. 
E)  The answer cannot be determined based on the information provided.

Question 8

Bacteria such as E. coli and Salmonella produce invasins that bind host cells, thus causing the cells to

Accepted Answer

A)  engulf the bacteria. 
B)  release TNF. 
C)  release cytokines. 
D)  produce iron- binding proteins. 
E)  destroy the bacteria. 
A)  engulf the bacteria. 
B)  release TNF. 
C)  release cytokines. 
D)  produce iron- binding proteins. 
E)  destroy the bacteria.

Question 9

The fimbriae of Neisseria gonorrhea and enteropathogenic E. coli are examples of

Accepted Answer

A)  adhesins. 
B)  receptors. 
C)  ligands. 
D)  adhesins and ligands. 
E)  adhesins, ligands, and receptors. 
A)  adhesins. 
B)  receptors. 
C)  ligands. 
D)  adhesins and ligands. 
E)  adhesins, ligands, and receptors.

Question 10

Which of the following contributes to the virulence of a pathogen?

Accepted Answer

A)  toxin production 
B)  evasion of host defenses 
C)  numbers of microorganisms that gain access to a host 
D)  numbers of microorganisms that gain access to a host and evasion of host defenses 
E)  numbers of microorganisms that gain access to a host, evasion of host defenses, and toxin production 
A)  toxin production 
B)  evasion of host defenses 
C)  numbers of microorganisms that gain access to a host 
D)  numbers of microorganisms that gain access to a host and evasion of host defenses 
E)  numbers of microorganisms that gain access to a host, evasion of host defenses, and toxin production

Question 11

All of the following are examples of entry via the parenteral route EXCEPT

Accepted Answer

A)  bite. 
B)  hair follicle. 
C)  surgery. 
D)  injection. 
E)  skin cut. 
A)  bite. 
B)  hair follicle. 
C)  surgery. 
D)  injection. 
E)  skin cut.

Question 12

The M protein enhances the virulence of Streptococcus by preventing phagocytosis.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following does NOT contribute to the symptoms of a fungal disease?

Accepted Answer

A)  toxins 
B)  allergic response of the host 
C)  capsules 
D)  cell walls 
E)  metabolic products 
A)  toxins 
B)  allergic response of the host 
C)  capsules 
D)  cell walls 
E)  metabolic products

Question 14

Siderophores are bacterial proteins that compete with the host's

Accepted Answer

A)  antibodies. 
B)  receptors. 
C)  red blood cells. 
D)  white blood cells. 
E)  iron- transport proteins. 
A)  antibodies. 
B)  receptors. 
C)  red blood cells. 
D)  white blood cells. 
E)  iron- transport proteins.

Question 15

Cholera toxin polypeptide A binds to surface gangliosides on target cells. If the gangliosides were removed,

Accepted Answer

A)  polypeptide A would bind to target cells. 
B)  polypeptide B would not be able to enter the cells. 
C)  polypeptide A would enter the cells. 
D)  Vibrio would bind to target cells. 
E)  Vibrio would not produce cholera toxin. 
A)  polypeptide A would bind to target cells. 
B)  polypeptide B would not be able to enter the cells. 
C)  polypeptide A would enter the cells. 
D)  Vibrio would bind to target cells. 
E)  Vibrio would not produce cholera toxin.

Question 16

Which of the following statements about exotoxins is generally FALSE?

Accepted Answer

A)  They are resistant to heat. 
B)  They are produced by gram- positive bacteria. 
C)  They are composed of proteins. 
D)  They are more potent than endotoxins. 
E)  They have specific methods of action. 
A)  They are resistant to heat. 
B)  They are produced by gram- positive bacteria. 
C)  They are composed of proteins. 
D)  They are more potent than endotoxins. 
E)  They have specific methods of action.

Question 17

Botulism is caused by ingestion of a proteinaceous exotoxin; therefore, it can easily be prevented by

Accepted Answer

A)  filtering food. 
B)  administering antibiotics to patients. 
C)  not eating canned food. 
D)  boiling food prior to consumption. 
E)  preventing fecal contamination of food. 
A)  filtering food. 
B)  administering antibiotics to patients. 
C)  not eating canned food. 
D)  boiling food prior to consumption. 
E)  preventing fecal contamination of food.

Question 18

All of the following are used by bacteria to attach to host cells EXCEPT

Accepted Answer

A)  ligands. 
B)  capsules. 
C)  M protein. 
D)  A- B toxins. 
E)  fimbriae. 
A)  ligands. 
B)  capsules. 
C)  M protein. 
D)  A- B toxins. 
E)  fimbriae.

Question 19

Symptoms of protozoan and helminthic diseases are due to

Accepted Answer

A)  tissue damage due to growth of the parasite on the tissues. 
B)  waste products excreted by the parasite. 
C)  products released from damaged tissues. 
D)  tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite. 
E)  tissue damage due to growth of the parasite on the tissues, waste products excreted by the parasite, and products released from damaged tissues. 
A)  tissue damage due to growth of the parasite on the tissues. 
B)  waste products excreted by the parasite. 
C)  products released from damaged tissues. 
D)  tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite. 
E)  tissue damage due to growth of the parasite on the tissues, waste products excreted by the parasite, and products released from damaged tissues.

Question 20

Which of the following statements is FALSE?

Accepted Answer

A)  Coagulase destroys blood clots. 
B)  Kinase destroys fibrin clots. 
C)  Hyaluronidase breaks down substances between cells. 
D)  Leukocidins destroy neutrophils. 
E)  Hemolysins lyse red blood cells. 
A)  Coagulase destroys blood clots. 
B)  Kinase destroys fibrin clots. 
C)  Hyaluronidase breaks down substances between cells. 
D)  Leukocidins destroy neutrophils. 
E)  Hemolysins lyse red blood cells.

Exam 15: Microbial Mechanisms of Pathogenicity

Ergot and aflatoxin are toxins sometimes found in grains contaminated with fungi.

Twenty- five people developed symptoms of nausea, vomiting, and diarrhea three to six hours after attending a church picnic where they ate a ham and green bean casserole with cream sauce. The most likely cause of this case of food intoxication is

Table 15.2 Bacterium ID 50 E. coli O157:H7 20 Legionella pneumophila 1 Shigella 10 Treponema pallicum 57 -Which organism in Table 15.2 most easily causes an infection?

Nonpathogenic Vibrio cholerae can acquire the cholera toxin gene by

Which of the following mechanisms is used by gram- negative bacteria to cross the blood- brain barrier?

The ID50is

Bacteria such as E. coli and Salmonella produce invasins that bind host cells, thus causing the cells to

The fimbriae of Neisseria gonorrhea and enteropathogenic E. coli are examples of

Which of the following contributes to the virulence of a pathogen?

All of the following are examples of entry via the parenteral route EXCEPT

The M protein enhances the virulence of Streptococcus by preventing phagocytosis.

Which of the following does NOT contribute to the symptoms of a fungal disease?

Siderophores are bacterial proteins that compete with the host's

Cholera toxin polypeptide A binds to surface gangliosides on target cells. If the gangliosides were removed,

Which of the following statements about exotoxins is generally FALSE?

Botulism is caused by ingestion of a proteinaceous exotoxin; therefore, it can easily be prevented by

All of the following are used by bacteria to attach to host cells EXCEPT

Symptoms of protozoan and helminthic diseases are due to

Which of the following statements is FALSE?

The Microbial World and You

Chemical Principles

Observing Microorganisms Through a Microscope

Functional Anatomy of Prokaryotic and Eukaryotic Cells

Microbial Metabolism

Microbial Growth

The Control of Microbial Growth

Microbial Genetics

Biotechnology and Recombinant Dna

Classification of Microorganisms

The Prokaryotes: Domains Bacteria and Archaea

The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

Viruses, Viroids, and Prions

Principles of Disease and Epidemiology

Innate Immunity: Nonspecific Defenses of the Host

Adaptive Immunity: Specific Defenses of the Host

Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

Microbial Diseases of the Skin and Eyes

Microbial Diseases of the Nervous System

Microbial Diseases of the Cardiovascular and Lymphatic Systems

Microbial Diseases of the Respiratory System

Microbial Diseases of the Digestive System

Microbial Diseases of the Urinary and Reproductive Systems

Environmental Microbiology

Applied and Industrial Microbiology

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