Question 1

Which statement regarding the pathogenesis of necrotizing fasciitis is INCORRECT?

Accepted Answer

A)  The causative agent produces SPE A, a superantigen that causes helper T cells to release large amounts of cytokines, leading to toxic shock. 
B)  SPE B is a protease produced by S. pyogenes that causes tissue death and breakdown, leading to fluid accumulation in the area and intense swelling. 
C)  A hyaluronic acid capsule and M protein allow the causative agent to evade the immune responses. 
D)  M protein-fibrinogen complexes causes neutrophils to release inflammatory molecules that increase vascular permeability and lead to a blood pressure drop. 
E)  The causative agent sheds antibodies that attach to fibrinogen and recruit natural killer cells that destroy muscle fascia through ADCC. 
A)  The causative agent produces SPE A, a superantigen that causes helper T cells to release large amounts of cytokines, leading to toxic shock. 
B)  SPE B is a protease produced by S. pyogenes that causes tissue death and breakdown, leading to fluid accumulation in the area and intense swelling. 
C)  A hyaluronic acid capsule and M protein allow the causative agent to evade the immune responses. 
D)  M protein-fibrinogen complexes causes neutrophils to release inflammatory molecules that increase vascular permeability and lead to a blood pressure drop. 
E)  The causative agent sheds antibodies that attach to fibrinogen and recruit natural killer cells that destroy muscle fascia through ADCC.

Question 2

Which statement regarding the treatment of tetanus is False?

Accepted Answer

A)  TIG antibodies bind to circulating toxin molecules, neutralizing their effects and providing passive immunity. 
B)  TIG neutralizes tetanospasmin that is already attached to nerve tissue, preventing damage to that nerve. 
C)  An antibacterial medication such as metronidazole is given to kill any actively multiplying bacterial cells. 
D)  The patient is given muscle relaxants and supportive care, including being placed on a ventilator if needed. 
E)  The person is given tetanus vaccine that results in the production of anti-tetanospasmin antibodies. 
A)  TIG antibodies bind to circulating toxin molecules, neutralizing their effects and providing passive immunity. 
B)  TIG neutralizes tetanospasmin that is already attached to nerve tissue, preventing damage to that nerve. 
C)  An antibacterial medication such as metronidazole is given to kill any actively multiplying bacterial cells. 
D)  The patient is given muscle relaxants and supportive care, including being placed on a ventilator if needed. 
E)  The person is given tetanus vaccine that results in the production of anti-tetanospasmin antibodies.

Question 3

Early work with Clostridium tetani and Corynebacterium diphtheriae demonstrated

Accepted Answer

A)  the importance of thoroughly cooking food. 
B)  the potential threat from spore-forming bacteria. 
C)  the usefulness of anti-viral medications. 
D)  that disease can be caused by bacterial toxins. 
E)  that all bacteria form spores. 
A)  the importance of thoroughly cooking food. 
B)  the potential threat from spore-forming bacteria. 
C)  the usefulness of anti-viral medications. 
D)  that disease can be caused by bacterial toxins. 
E)  that all bacteria form spores.

Question 4

The fungal disease that may be associated with gardening is

Accepted Answer

A)  candidiasis. 
B)  actinomycosis. 
C)  tinea capitis. 
D)  sporotrichosis. 
E)  histoplasmosis. 
A)  candidiasis. 
B)  actinomycosis. 
C)  tinea capitis. 
D)  sporotrichosis. 
E)  histoplasmosis.

Question 5

The disease most feared to develop after an animal bite is

Accepted Answer

A)  tetanus. 
B)  rabies. 
C)  gas gangrene. 
D)  streptobacillary rat bite fever. 
E)  necrotizing fasciitis. 
A)  tetanus. 
B)  rabies. 
C)  gas gangrene. 
D)  streptobacillary rat bite fever. 
E)  necrotizing fasciitis.

Question 6

Streptobacillus moniliformis is unusual in that it spontaneously forms L-forms.

Accepted Answer

A) True 
 B)False

Question 7

How may lung damage or pneumonia occur in a person with tetanus?

Accepted Answer

A)  Spasms of major chest muscles may be so severe that the lungs are damaged. 
B)  Tetanospasmin is an A-B toxin that binds to lung epithelial cells, killing them. 
C)  C. tetani releases alpha-toxin that causes the alveoli of the lungs to collapse. 
D)  The person may inhale regurgitated (vomited) stomach contents. 
E)  Tetanospasmin causes the release of degradative enzymes in the lungs. 
A)  Spasms of major chest muscles may be so severe that the lungs are damaged. 
B)  Tetanospasmin is an A-B toxin that binds to lung epithelial cells, killing them. 
C)  C. tetani releases alpha-toxin that causes the alveoli of the lungs to collapse. 
D)  The person may inhale regurgitated (vomited) stomach contents. 
E)  Tetanospasmin causes the release of degradative enzymes in the lungs.

Question 8

Why is it difficult to treat P. aeruginosa wound infections?

Accepted Answer

A)  The organism is resistant to multiple different antibiotics. 
B)  P. aeruginosa forms biofilms, which protect the bacteria. 
C)  The organism is resistant to multiple different antibiotics AND P. aeruginosa forms biofilms, which protect the bacteria. 
D)  The organism is resistant to multiple different antibiotics AND P. aeruginosa forms endospores which are extremely hardy and difficult to destroy. 
E)  P. aeruginosa forms endospores which are extremely hardy and difficult to destroy. 
A)  The organism is resistant to multiple different antibiotics. 
B)  P. aeruginosa forms biofilms, which protect the bacteria. 
C)  The organism is resistant to multiple different antibiotics AND P. aeruginosa forms biofilms, which protect the bacteria. 
D)  The organism is resistant to multiple different antibiotics AND P. aeruginosa forms endospores which are extremely hardy and difficult to destroy. 
E)  P. aeruginosa forms endospores which are extremely hardy and difficult to destroy.

Question 9

Formation of biofilms attached to fibronectin and fibrinogen coating plastic devices like catheters and heart valves is a virulence mechanism of

Accepted Answer

A)  Staphylococcus. 
B)  Streptococcus. 
C)  Clostridium. 
D)  Pseudomonas. 
E)  Escherichia. 
A)  Staphylococcus. 
B)  Streptococcus. 
C)  Clostridium. 
D)  Pseudomonas. 
E)  Escherichia.

Question 10

Why are signs and symptoms not quickly resolved in a person with tetanus when they are given antibiotics?

Accepted Answer

A)  Clostridium tetani is an acid-fast organism; it thus has a waxy cell wall that prevents antibiotics from entering the cell. 
B)  Antibiotics will prevent the production of additional tetanospasmin but will not repair nerves already damaged by the toxin. 
C)  The antibiotics are given prophylactically, to prevent secondary infections. Nerves damaged by tetanospasmin need time to repair. 
D)  Clostridium tetani is resistant to most antibiotics; treatment thus involves several weeks of combined antibiotic therapy. 
E)  Clostridium tetani is an acid-fast organism; it thus has a slow generation time, so it takes several weeks for an antibiotic to be effective in killing the cells. 
A)  Clostridium tetani is an acid-fast organism; it thus has a waxy cell wall that prevents antibiotics from entering the cell. 
B)  Antibiotics will prevent the production of additional tetanospasmin but will not repair nerves already damaged by the toxin. 
C)  The antibiotics are given prophylactically, to prevent secondary infections. Nerves damaged by tetanospasmin need time to repair. 
D)  Clostridium tetani is resistant to most antibiotics; treatment thus involves several weeks of combined antibiotic therapy. 
E)  Clostridium tetani is an acid-fast organism; it thus has a slow generation time, so it takes several weeks for an antibiotic to be effective in killing the cells.

Question 11

A striking feature of Clostridium tetani that differentiates it from other pathogenic species of Clostridium is its ability to

Accepted Answer

A)  produce a greenish pigment. 
B)  grow in strictly anaerobic conditions. 
C)  grow in strictly aerobic conditions. 
D)  produce endospores. 
E)  form terminally located, spherical spores. 
A)  produce a greenish pigment. 
B)  grow in strictly anaerobic conditions. 
C)  grow in strictly aerobic conditions. 
D)  produce endospores. 
E)  form terminally located, spherical spores.

Question 12

The toxin implicated in C. perfringens toxicity is

Accepted Answer

A)  tetanospasmin. 
B)  exoenzyme S. 
C)  alpha toxin. 
D)  endoenzyme T. 
E)  beta toxin. 
A)  tetanospasmin. 
B)  exoenzyme S. 
C)  alpha toxin. 
D)  endoenzyme T. 
E)  beta toxin.

Question 13

Which of the following does not usually result from a wound infection?

Accepted Answer

A)  Delayed healing. 
B)  Aerobic conditions. 
C)  Abscess formation. 
D)  Bacterial spread. 
E)  These all result from delayed wound healing. 
A)  Delayed healing. 
B)  Aerobic conditions. 
C)  Abscess formation. 
D)  Bacterial spread. 
E)  These all result from delayed wound healing.

Question 14

You are looking after your sister's cat Singa. While playing one evening, Singa accidentally bites you instead of the toy mouse you are holding. The bite wound is very small but is in the fleshy part of your hand. You wash the wound, which is not bleeding much, and put a band aid on it. The next day, your whole hand is red, swollen, and painful, and some lymph nodes in your arm are enlarged and tender. You call your sister, who is an RN. She urges you to go to the doctor, telling you that animal bites can sometimes be infected, and that if that is the case, you will need treatment before the infection gets any worse.
-The PA tells you that a disease called cat scratch disease can also be contracted through a cat bite. The organism that causes this disease is ________, and that the disease is characterized by ________.

Accepted Answer

A)  Bartonella henselae; peliosis hepatis 
B)  Pasteurella multocida; local lymph node enlargement 
C)  Bartonella henselae; local lymph node enlargement 
D)  Pasteurella multocida; rash and joint pain 
E)  Streptobacillus moniliformis; vomiting, diarrhea and rash 
A)  Bartonella henselae; peliosis hepatis 
B)  Pasteurella multocida; local lymph node enlargement 
C)  Bartonella henselae; local lymph node enlargement 
D)  Pasteurella multocida; rash and joint pain 
E)  Streptobacillus moniliformis; vomiting, diarrhea and rash

Question 15

Why is it not surprising that staphylococci are the most common cause of wound infections?

Accepted Answer

A)  Many people carry staphylococci as part of their normal microbiota. 
B)  Staphylococci are resistant to most common disinfectants. 
C)  Unlike other pathogens, the organism evades the immune system very effectively. 
D)  Staphylococci are encapsulated. 
E)  Staphylococci are Gram-negative and contain LPS. 
A)  Many people carry staphylococci as part of their normal microbiota. 
B)  Staphylococci are resistant to most common disinfectants. 
C)  Unlike other pathogens, the organism evades the immune system very effectively. 
D)  Staphylococci are encapsulated. 
E)  Staphylococci are Gram-negative and contain LPS.

Question 16

Which is True about protein A, produced by S. aureus?

Accepted Answer

A)  It binds to the Fc region of antibody AND it enhances binding of phagocytes. 
B)  It binds to the Fc region of antibody AND it hides bacteria from phagocytes. 
C)  It hides bacteria from phagocytes AND it digests antibodies. 
D)  It enhances binding of phagocytes AND it digests antigens. 
E)  It binds to the Fab region of antibody AND it hides bacteria from phagocytes. 
A)  It binds to the Fc region of antibody AND it enhances binding of phagocytes. 
B)  It binds to the Fc region of antibody AND it hides bacteria from phagocytes. 
C)  It hides bacteria from phagocytes AND it digests antibodies. 
D)  It enhances binding of phagocytes AND it digests antigens. 
E)  It binds to the Fab region of antibody AND it hides bacteria from phagocytes.

Question 17

The infectious agent(s) that may arise in a wound from a human bite is/are

Accepted Answer

A)  Escherichia coli. 
B)  Bacteroides species. 
C)  Bartonella henselae. 
D)  Staphylococcus aureus. 
E)  Bacteroides species AND Staphylococcus aureus. 
A)  Escherichia coli. 
B)  Bacteroides species. 
C)  Bartonella henselae. 
D)  Staphylococcus aureus. 
E)  Bacteroides species AND Staphylococcus aureus.

Question 18

Why is it not surprising that Staphylococci are the leading cause of wound infections?

Accepted Answer

A)  This genus is readily present as a part of the normal microbiota on most people's skin, so it could easily enter wounds. 
B)  Members of this genus are all particularly virulent and highly capable of causing numerous infections. 
C)  Staphylococci cannot be eradicated from the skin due to multidrug resistance in most members of the genus. Drugs simply don't kill them. 
D)  Staphylococci acquire antibiotic resistance very readily, making them hard to eliminate by pre-surgical antibacterial soaps. As such, they commonly infect surgical wound sites. 
E)  Staphylococci form endospores, so even with appropriate control measures, there is a high risk that spores will enter a wound and cause infection. 
A)  This genus is readily present as a part of the normal microbiota on most people's skin, so it could easily enter wounds. 
B)  Members of this genus are all particularly virulent and highly capable of causing numerous infections. 
C)  Staphylococci cannot be eradicated from the skin due to multidrug resistance in most members of the genus. Drugs simply don't kill them. 
D)  Staphylococci acquire antibiotic resistance very readily, making them hard to eliminate by pre-surgical antibacterial soaps. As such, they commonly infect surgical wound sites. 
E)  Staphylococci form endospores, so even with appropriate control measures, there is a high risk that spores will enter a wound and cause infection.

Question 19

Would babies need to be immunized against lockjaw (tetanus) if their mother had been immunized against the disease?  Why or why not?

Accepted Answer

A)  No, because the mother's IgG antibodies would be passed along through the placenta before birth, protecting the baby from the infection. 
B)  Yes, because even though maternal IgG antibodies might be passed along through the placenta, they will not last forever. The baby will need to create its own antibody response to be protected against future tetanus. 
C)  No, because maternal IgG antibodies would be passed along in the breast milk, protecting the baby from infection. 
D)  Yes, because the maternal response to the tetanus vaccine is to produce IgE antibodies, and IgD antibodies are the predominant type in breast milk. Therefore, even if the baby is breast-fed, it won't receive the mother's protective antibodies. 
E)  Yes, because although the mother will make IgG antibodies in response to the vaccine, these antibodies cannot cross the placenta, so the baby is not protected at all. 
A)  No, because the mother's IgG antibodies would be passed along through the placenta before birth, protecting the baby from the infection. 
B)  Yes, because even though maternal IgG antibodies might be passed along through the placenta, they will not last forever. The baby will need to create its own antibody response to be protected against future tetanus. 
C)  No, because maternal IgG antibodies would be passed along in the breast milk, protecting the baby from infection. 
D)  Yes, because the maternal response to the tetanus vaccine is to produce IgE antibodies, and IgD antibodies are the predominant type in breast milk. Therefore, even if the baby is breast-fed, it won't receive the mother's protective antibodies. 
E)  Yes, because although the mother will make IgG antibodies in response to the vaccine, these antibodies cannot cross the placenta, so the baby is not protected at all.

Question 20

Staphylococci are the leading cause of wound infections.

Accepted Answer

A) True 
 B)False

Exam 23: Wound Infections

Which statement regarding the pathogenesis of necrotizing fasciitis is INCORRECT?

Which statement regarding the treatment of tetanus is False?

Early work with Clostridium tetani and Corynebacterium diphtheriae demonstrated

The fungal disease that may be associated with gardening is

The disease most feared to develop after an animal bite is

Streptobacillus moniliformis is unusual in that it spontaneously forms L-forms.

How may lung damage or pneumonia occur in a person with tetanus?

Why is it difficult to treat P. aeruginosa wound infections?

Formation of biofilms attached to fibronectin and fibrinogen coating plastic devices like catheters and heart valves is a virulence mechanism of

Why are signs and symptoms not quickly resolved in a person with tetanus when they are given antibiotics?

A striking feature of Clostridium tetani that differentiates it from other pathogenic species of Clostridium is its ability to

The toxin implicated in C. perfringens toxicity is

Which of the following does not usually result from a wound infection?

Why is it not surprising that staphylococci are the most common cause of wound infections?

Which is True about protein A, produced by S. aureus?

The infectious agent(s) that may arise in a wound from a human bite is/are

Why is it not surprising that Staphylococci are the leading cause of wound infections?

Would babies need to be immunized against lockjaw (tetanus) if their mother had been immunized against the disease? Why or why not?

Staphylococci are the leading cause of wound infections.

Humans and the Microbial World

The Molecules of Life

Microscopy and Cell Structure

Dynamics of Microbial Growth

Control of Microbial Growth

Microbial Metabolism: Fueling Cell Growth

The Blueprint of Life, from DNA to Protein

Bacterial Genetics

Biotechnology

Identifying and Classifying Microorganisms

The Diversity of Bacteria and Archaea

The Eukaryotic Members of the Microbial World

Viruses, Viroids, and Prions

The Innate Immune Response

The Adaptive Immune Response

Host-Microbe Interactions

Immunological Disorders

Applications of Immune Responses

Epidemiology

Antimicrobial Medications

Respiratory System Infections

Skin Infections

Digestive System Infections

Blood and Lymphatic Infections

Nervous System Infections

Genitourinary Tract Infections

Microbial Ecology

Environmental Microbiology: Treatment of Water, Wastes, and Polluted Habitats

Food Microbiology

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