Question 1

Gram- negative septic shock results from the following events. What is the second step?

Accepted Answer

A)  Fever occurs. 
B)  Phagocytes ingest gram- negative bacteria. 
C)  LPS is released from gram- negative bacteria. 
D)  Body temperature is reset in the hypothalamus. 
E)  IL- 1 is released. 
A)  Fever occurs. 
B)  Phagocytes ingest gram- negative bacteria. 
C)  LPS is released from gram- negative bacteria. 
D)  Body temperature is reset in the hypothalamus. 
E)  IL- 1 is released. C

Question 2

Which of the following statements about exotoxins is generally not true?

Accepted Answer

A)  They are produced by gram- positive bacteria. 
B)  They are composed of proteins. 
C)  They are not destroyed by heat. 
D)  They have specific methods of action. 
E)  They are more potent than endotoxins. 
A)  They are produced by gram- positive bacteria. 
B)  They are composed of proteins. 
C)  They are not destroyed by heat. 
D)  They have specific methods of action. 
E)  They are more potent than endotoxins. C

Question 3

Cytopathic effects are changes in host cells due to

Accepted Answer

A)  Protozoan and helminthic infections. 
B)  Viral infections. 
C)  Bacterial infections. 
D)  Fungal infections. 
E)  All of the above. 
A)  Protozoan and helminthic infections. 
B)  Viral infections. 
C)  Bacterial infections. 
D)  Fungal infections. 
E)  All of the above. B

Question 4

Which of the following is not a membrane- disrupting toxin?

Accepted Answer

A)  Streptolysin O 
B)  Leucocidin 
C)  Hemolysin 
D)  A- B toxin 
E)  Streptolysin S 
A)  Streptolysin O 
B)  Leucocidin 
C)  Hemolysin 
D)  A- B toxin 
E)  Streptolysin S

Question 5

Which is a method of avoiding phagocytosis?

Accepted Answer

A)  Inducing TNF 
B)  Producing fimbriae 
C)  Inducing endocytosis 
D)  Producing toxins 
E)  All of the above 
A)  Inducing TNF 
B)  Producing fimbriae 
C)  Inducing endocytosis 
D)  Producing toxins 
E)  All of the above

Question 6

All of the following may be used for adherence except

Accepted Answer

A)  Cell membrane mannose. 
B)  Lipoproteins. 
C)  Glycoproteins. 
D)  Capsules. 
E)  Fimbriae. 
A)  Cell membrane mannose. 
B)  Lipoproteins. 
C)  Glycoproteins. 
D)  Capsules. 
E)  Fimbriae.

Question 7

The most frequently used portal of entry for pathogens is the

Accepted Answer

A)  Parenteral route. 
B)  Mucous membranes of the respiratory tract. 
C)  Mucous membranes of the gastrointestinal tract. 
D)  Skin. 
E)  All are used equally. 
A)  Parenteral route. 
B)  Mucous membranes of the respiratory tract. 
C)  Mucous membranes of the gastrointestinal tract. 
D)  Skin. 
E)  All are used equally.

Question 8

The symptoms of tetanus are due to

Accepted Answer

A)  Encapsulated Clostridium tetani. 
B)  An exotoxin produced by Clostridium tetani. 
C)  The growth of Clostridium tetani in a wound. 
D)  Hemolysins produced by Clostridium tetani. 
E)  All of the above. 
A)  Encapsulated Clostridium tetani. 
B)  An exotoxin produced by Clostridium tetani. 
C)  The growth of Clostridium tetani in a wound. 
D)  Hemolysins produced by Clostridium tetani. 
E)  All of the above.

Question 9

Endotoxins are

Accepted Answer

A)  Excreted from the cell. 
B)  Specific in their method of action. 
C)  Part of the gram- negative cell wall. 
D)  Associated with gram- positive bacteria. 
E)  None of the above. 
A)  Excreted from the cell. 
B)  Specific in their method of action. 
C)  Part of the gram- negative cell wall. 
D)  Associated with gram- positive bacteria. 
E)  None of the above.

Question 10

Which of the following is not used for attachment to a host?

Accepted Answer

A)  Ligands 
B)  M protein 
C)  Fimbriae 
D)  Capsules 
E)  None of the above. 
A)  Ligands 
B)  M protein 
C)  Fimbriae 
D)  Capsules 
E)  None of the above.

Question 11

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

Accepted Answer

A)  Polypeptide B would not be able to enter the cells. 
B)  Polypeptide A would enter the cells. 
C)  Polypeptide A would bind to target cells. 
D)  Vibrio would not produce cholera toxin. 
E)  None of the above. 
A)  Polypeptide B would not be able to enter the cells. 
B)  Polypeptide A would enter the cells. 
C)  Polypeptide A would bind to target cells. 
D)  Vibrio would not produce cholera toxin. 
E)  None of the above.

Question 12

Which of the following organisms doesn't produce an exotoxin?

Accepted Answer

A)  Clostridium botulinum 
B)  Corynebacterium diphtheriae 
C)  Staphylococcus aureus 
D)  Salmonella typhi 
E)  Clostridium tetani 
A)  Clostridium botulinum 
B)  Corynebacterium diphtheriae 
C)  Staphylococcus aureus 
D)  Salmonella typhi 
E)  Clostridium tetani

Question 13

Which of the following does not contribute to the virulence of a pathogen?

Accepted Answer

A)  Numbers of microorganisms that gain access to a host 
B)  Toxins 
C)  Cell wall 
D)  Enzymes 
E)  None of the above 
A)  Numbers of microorganisms that gain access to a host 
B)  Toxins 
C)  Cell wall 
D)  Enzymes 
E)  None of the above

Question 14

Poliovirus is ingested and gains access to tissues by which portal of entry?

Accepted Answer

A)  Parenteral 
B)  Skin 
C)  Mucous membranes 
D)  All of the above 
E)  None of the above 
A)  Parenteral 
B)  Skin 
C)  Mucous membranes 
D)  All of the above 
E)  None of the above

Question 15

Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth. This indicates that

Accepted Answer

A)  Bacteria that cause periodontal disease adhere to teeth. 
B)  Streptococci cause periodontal disease. 
C)  Streptococci get bacterial infections. 
D)  Streptococcal colonization is necessary for periodontal disease. 
E)  Bacteria that cause periodontal disease adhere to gums and teeth. 
A)  Bacteria that cause periodontal disease adhere to teeth. 
B)  Streptococci cause periodontal disease. 
C)  Streptococci get bacterial infections. 
D)  Streptococcal colonization is necessary for periodontal disease. 
E)  Bacteria that cause periodontal disease adhere to gums and teeth.

Question 16

A cell wall can increase a bacterium's virulence because cell wall lipid A

Accepted Answer

A)  Helps the bacterium attach. 
B)  Destroys host tissues. 
C)  Resists phagocytosis. 
D)  All bacteria have a cell wall and all are not pathogenic; therefore, cell walls do not contribute to virulence. 
E)  None of the above. 
A)  Helps the bacterium attach. 
B)  Destroys host tissues. 
C)  Resists phagocytosis. 
D)  All bacteria have a cell wall and all are not pathogenic; therefore, cell walls do not contribute to virulence. 
E)  None of the above.

Question 17

In response to the presence of endotoxin, phagocytes secrete tumor necrosis factor. This causes

Accepted Answer

A)  A fever. 
B)  A decrease in blood pressure. 
C)  The disease to subside. 
D)  A gram- negative infection. 
E)  None of the above. 
A)  A fever. 
B)  A decrease in blood pressure. 
C)  The disease to subside. 
D)  A gram- negative infection. 
E)  None of the above.

Question 18

All of the following are true about M protein except

Accepted Answer

A)  It is a protein. 
B)  It is found on fimbriae. 
C)  It is heat- and acid- resistant. 
D)  It is readily digested by phagocytes. 
E)  It is found on Streptococcus pyogenes. 
A)  It is a protein. 
B)  It is found on fimbriae. 
C)  It is heat- and acid- resistant. 
D)  It is readily digested by phagocytes. 
E)  It is found on Streptococcus pyogenes.

Question 19

Pseudomonas aeruginosa produces a two- part exotoxin. The most likely pathologic effect of this toxin is

Accepted Answer

A)  A red rash. 
B)  Tetani or lockjaw. 
C)  Flaccid paralysis. 
D)  The bacteria will be able to grow in phagocytes. 
E)  Inhibition of protein synthesis. 
A)  A red rash. 
B)  Tetani or lockjaw. 
C)  Flaccid paralysis. 
D)  The bacteria will be able to grow in phagocytes. 
E)  Inhibition of protein synthesis.

Question 20

Injectable drugs are tested for endotoxins by

Accepted Answer

A)  Filtering out the cells. 
B)  Looking for turbidity. 
C)  The Limulus amoebocyte lysate test. 
D)  Counting the viable bacteria. 
E)  None of the above. 
A)  Filtering out the cells. 
B)  Looking for turbidity. 
C)  The Limulus amoebocyte lysate test. 
D)  Counting the viable bacteria. 
E)  None of the above.

Exam 15: Microbial Mechanisms of Pathogenicity

Gram- negative septic shock results from the following events. What is the second step?

Which of the following statements about exotoxins is generally not true?

Cytopathic effects are changes in host cells due to

Which of the following is not a membrane- disrupting toxin?

Which is a method of avoiding phagocytosis?

All of the following may be used for adherence except

The most frequently used portal of entry for pathogens is the

The symptoms of tetanus are due to

Endotoxins are

Which of the following is not used for attachment to a host?

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

Which of the following organisms doesn't produce an exotoxin?

Which of the following does not contribute to the virulence of a pathogen?

Poliovirus is ingested and gains access to tissues by which portal of entry?

Bacteria that cause periodontal disease have adhesins for receptors on streptococci that colonize on teeth. This indicates that

A cell wall can increase a bacterium's virulence because cell wall lipid A

In response to the presence of endotoxin, phagocytes secrete tumor necrosis factor. This causes

All of the following are true about M protein except

Pseudomonas aeruginosa produces a two- part exotoxin. The most likely pathologic effect of this toxin is

Injectable drugs are tested for endotoxins by

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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