MICB 202 Study Guide - Final Guide: Sepsis, Hospital-Acquired Infection, Bacteremia

1. Select which of the following are mechanisms used by pathogens to avoid host defenses and to successfully colonize the host.

A. Producing siderphores to obtain iron from the host for growth

B. producing adhesins for damaging host cells

C. Avoiding IgA proteases for avoiding secretory IgA

D. Avoiding secretory IgA by rapid turnover of pili

E. Producing toxic substances to suppress host responses

2. People considered obese have a different normal flora in the gastrointestinal tract compared to people who are considered lean.

A. true

B. false

3. Which of the following is NOT a mechanism used by pathogens for avoiding or surviving phagocytosis?

A. Killing macrophages and neutrophils

B. Colonizing the phagocyte

C. inhibiting opsonization

D. Inhibiting phagocte chemotaxis

E. these are all methods of avoiding or surviving phagocytosis

4.Which of the following immune responses is best suited to prevent a virus from infecting a cell?

A. complement cascade

B. inflammation

C. Virus-specific antibodies

D. Fever

E. phagocytic cells

5. Which of the following is NOT a method used by pathogens for penetrating skin or mucous membranes?

A. Injection of effector proteins that induce endocytosis

B. Exploiting antigen-sampling processes

C. these are all mechanisms for penetrating skin or mucous membranes

D. Exploiting an injury

E. Production of endotoxin

6. Antibodies, which are produced as part of the adaptive immune response, can sometimes be damaging rather than beneficial. People suffering from an autoimmune disease called antiphospholipid antibody syndrome (APS) make antibodies that bind to phospholipids. Some of the signs and symptoms affected individuals experience are blood clots, stroke, heart attack, and kidney damage. What is the likely cause of these symptoms?

A. the anti-phospholipid antibodies cuse immune complexes that lodge in the affected organs

B. The person fails to make protective antibodies

C. The anti-phospholipid antibodies weaken certain organs that contain fat

D. the person makes antibodies that bind inappropriately to bacterial capsules, preventing phagocytosis of these cells

E. Cell damage caused by binding of these antibodies initates inappropriate coagulation events which inferfere with blood flow in affected organs.

7. Only Gram-positive bacteria produce exotoxins

A. true

B. False

8. Which of the following members of the normal microbiota inhibit the growth of Candida albicans?

A. Lactobacilus species

B. Staphylococci species

C. E. coli

D. Neisseria species

E. Propionibacterium species

9. Would an antibody response against the B subunit of an A-B toxin protect against the effects of the toxin?

A. yes. if antibodies bind to the B protion, the toxin can no longer bind to target cells and will thus not affect those cells

B. No, even if antibodies bindto the B portion of the toxin, it is the A portion that actually causes damage to the cell

C. This question cannot be answer. The immune system does not mount a strong response against proteins, so this situation is unlikely to occur.

D. Yes, if antibodies bind to the B protein, that portion of the toxin does not become activated, and thus does not damage the host cell

E. No, even if antiibodies bind to the B portion of the toxin, the toxin is still taken into the host cell by phagocytosis, damaging that cell

10. Please select the correct definition of balanced pathogenicity.

A. A host-parasite relationship in which the parasite persists in the host, causing maximal harm. The pathogen becomes more virulent while the host becomes increasingly susceptible.

B. A mechanism that allows bacteria to transfer gene products directly into host cells, inducing changes such as altering the cell's cytoskeleton structure

C. A generated balance in the microbiome that may be caused by taking antimicrobial medication. it generally helps the host maintain optimal health

D. A situation in which an abnormally high number of T-helper cells are stimulated, causing a massive release of cytokines.

E. A host-parasite relationship in which the parasite persists in the host while causing minimal harm. The pathogen becomes less virulent while the host becomes less susceptible

11. Bacteria may survive phagocytosis by

A. preventing encounters with phagocytes AND preventing fusion of two pathogosomes

B. avoiding recognition and attachment of lymphocytes AND lysinf the phagosomes

C. preventing fusion of the lysosome with the phagosome AND mimicking host molecules

D. lysing the phagosome AND mimicking host molecules

E. preventing fusion of the lysosome with the phagosome AND lysing the phagosome

1. Select which of the following are mechanisms used by pathogens to avoid host defenses and to successfully colonize the host.

A. Producing siderphores to obtain iron from the host for growth

B. producing adhesins for damaging host cells

C. Avoiding IgA proteases for avoiding secretory IgA

D. Avoiding secretory IgA by rapid turnover of pili

E. Producing toxic substances to suppress host responses

2. People considered obese have a different normal flora in the gastrointestinal tract compared to people who are considered lean.

A. true

B. false

3. Which of the following is NOT a mechanism used by pathogens for avoiding or surviving phagocytosis?

A. Killing macrophages and neutrophils

B. Colonizing the phagocyte

C. inhibiting opsonization

D. Inhibiting phagocte chemotaxis

E. these are all methods of avoiding or surviving phagocytosis

4.Which of the following immune responses is best suited to prevent a virus from infecting a cell?

A. complement cascade

B. inflammation

C. Virus-specific antibodies

D. Fever

E. phagocytic cells

5. Which of the following is NOT a method used by pathogens for penetrating skin or mucous membranes?

A. Injection of effector proteins that induce endocytosis

B. Exploiting antigen-sampling processes

C. these are all mechanisms for penetrating skin or mucous membranes

D. Exploiting an injury

E. Production of endotoxin

6. Antibodies, which are produced as part of the adaptive immune response, can sometimes be damaging rather than beneficial. People suffering from an autoimmune disease called antiphospholipid antibody syndrome (APS) make antibodies that bind to phospholipids. Some of the signs and symptoms affected individuals experience are blood clots, stroke, heart attack, and kidney damage. What is the likely cause of these symptoms?

A. the anti-phospholipid antibodies cuse immune complexes that lodge in the affected organs

B. The person fails to make protective antibodies

C. The anti-phospholipid antibodies weaken certain organs that contain fat

D. the person makes antibodies that bind inappropriately to bacterial capsules, preventing phagocytosis of these cells

E. Cell damage caused by binding of these antibodies initates inappropriate coagulation events which inferfere with blood flow in affected organs.

7. Only Gram-positive bacteria produce exotoxins

A. true

B. False

8. Which of the following members of the normal microbiota inhibit the growth of Candida albicans?

A. Lactobacilus species

B. Staphylococci species

C. E. coli

D. Neisseria species

E. Propionibacterium species

9. Would an antibody response against the B subunit of an A-B toxin protect against the effects of the toxin?

A. yes. if antibodies bind to the B protion, the toxin can no longer bind to target cells and will thus not affect those cells

B. No, even if antibodies bindto the B portion of the toxin, it is the A portion that actually causes damage to the cell

C. This question cannot be answer. The immune system does not mount a strong response against proteins, so this situation is unlikely to occur.

D. Yes, if antibodies bind to the B protein, that portion of the toxin does not become activated, and thus does not damage the host cell

E. No, even if antiibodies bind to the B portion of the toxin, the toxin is still taken into the host cell by phagocytosis, damaging that cell

10. Please select the correct definition of balanced pathogenicity.

A. A host-parasite relationship in which the parasite persists in the host, causing maximal harm. The pathogen becomes more virulent while the host becomes increasingly susceptible.

B. A mechanism that allows bacteria to transfer gene products directly into host cells, inducing changes such as altering the cell's cytoskeleton structure

C. A generated balance in the microbiome that may be caused by taking antimicrobial medication. it generally helps the host maintain optimal health

D. A situation in which an abnormally high number of T-helper cells are stimulated, causing a massive release of cytokines.

E. A host-parasite relationship in which the parasite persists in the host while causing minimal harm. The pathogen becomes less virulent while the host becomes less susceptible

11. Bacteria may survive phagocytosis by

A. preventing encounters with phagocytes AND preventing fusion of two pathogosomes

B. avoiding recognition and attachment of lymphocytes AND lysinf the phagosomes

C. preventing fusion of the lysosome with the phagosome AND mimicking host molecules

D. lysing the phagosome AND mimicking host molecules

E. preventing fusion of the lysosome with the phagosome AND lysing the phagosome

12. In two of Koch's postulates (#2 and #3), a pure culture of the organism is required. Which of the following would NOT be a possible consequence of using a contaminated culture?

A. these would all be consequences of using contaminated cultures

B. Even though there's a contaminating microbe present, as long as the original suspect microbe is also present, the disease should still manifest in test animals and the organism should still be recoverable from test animals. As such, there's really no consequence to using a contaminated culture

C. The problem is that one microbe may be toxic to other. It may have killed all of your suspect microbe in the culture. Therefore, you can't be sure that you're infecting your test animals with the microbe you suspect is causing the illness, or if it's only the sec. microbe.

D. you can't necessarily attribute the illness directly to the microbe in question; it may in fact be caused by the contaminating microbe

E. There's the possibility that the test animal might be acutely susceptible to the contaminating microbe, but completely resistant to the microbe you suspect causes the illness of interest. As such, when you introduce it into the test animal, it could confuse your final results.

Highlight or bold the answer you select for multiple choice or type in your answer in the blank space provided.

1. Which of the following is not true of the nervous system?

Consists of central and peripheral systems

(b) Central nervous system is composed of brain and spinal cord

(c) Ganglia are part of brain

(d) Meninges are membranes that cover brain and spinal cord

(e) Normally free of microbes

2. Which of the following is a common cause of meningitis in nonimmunized young children?

(a) Streptococcus pneumoniae

(b) Escherichia coli

(c) Staphylococcus

(d) Haemophilus influenzae

(e) None of the above

3. A complication of infection with this organism (Waterhouse-Friderichsen syndrome) can occur if the organism becomes widely distributed in the body, leading to endotoxin shock and death. The organism is:

(a) Haemophilus influenzae type A

(b) Neisseria meningitidis

(c) Haemophilus influenzae type B

(d) Streptococcus pneumoniae

(e) Listeria monocytogenes

4. Which of the following bacterial meningitis diseases currently is the most common type in the U.S., with increased incidences in infants and in the 15- to 24-year-old age group, and has three types or strains of the infectious microbe?

(a) Haemophilus meningitis

(b) Listeriosis

(c) Streptococcus meningitis

(d) Meningococcal meningitis

(e) a and c

5. Before development of a vaccine against this microbe, the disease it caused accounted for two-thirds of bacterial meningitis cases during the first year of life but is still the number one leading cause of mental retardation in patients who survive serious disease due to permanent central nervous system disorders. What is the microorganism?

(a) Haemophilus influenzae type B

(b) Haemophilus influenzae type A

(c) Neisseria meningitidis

(d) Streptococcus pneumoniae

(e) Listeria monocytogenes

6. Which of the following bacteria that may cause meningitis is Gram-positive and therefore does not cause endotoxin shock in infected individuals?

(a) Escherichia coli

(b) Neisseria meningitidis

(c) Listeria monocytogenes

(d) Haemophilus influenzae type B

(e) None of these

7. Avid swimmers and hot tub enthusiasts sometimes acquire an opportunistic infection caused by Naegleria fowleri that results in a meningoencephalitis. This organism is a (an):

(a) Protist

(b) Helminth

(c) Bacteria

(d) Amoeba

(e) a and d

8. Which of the following in NOT true about listeriosis?

(a) Foodborne transmission is the most common source of infection.

(b) It is a leading cause of bacterial meningitis today.

(c) It is responsible for many cases of fetal damage and death.

(d) It is sometimes acquired as a zoonosis.

(e) Individuals with impaired immune systems are highly susceptible to this disease.

9. Viral meningitis is usually always fatal if untreated, unlike bacterial meningitis, which is always self-limiting and nonfatal. True or false?

10. Which of the following is acid-fast and causes Hansen's disease?

(a) Mycobacterium tuberculosis

(b) Clostridium tetani

(c) Neisseria meningitidis

(d) Haemophilus influenzae

(e) Mycobacterium leprae

11. An immunofluorescent antibody test (IFAT) has replaced the older test for the presence of inclusions in neurons (Negri bodies) for the detection of infections caused by:

(a) Neisseria meningitidis

(b) Enteroviruses

(c) Mumps virus

(d) Rabies virus

(e) Haemophilus influenza

12. The viruses that cause encephalitis are most likely to be:

(a) Togaviruses

(b) Enteroviruses

(c) Mumps virus

(d) Rabies virus

(e) Hepatitis viruses

13. What do the following viral encephalitis diseases have in common: eastern equine encephalitis, western equine encephalitis, Venezuelan equine encephalitis, St. Louis encephalitis, West Nile fever?

(a) They are all caused by the same virus.

(b) They are have the horse as a common intermediate host.

(c) They are all transmitted into the body through the bite of an infected mosquito.

(d) Birds are never involved in the life cycle of the viruses that cause these diseases.

(e) Both a and d.

14. The only bacterium known to damage peripheral nerves is:

(a) Naegleria fowleri

(b) Mycobacterium leprae

(c) Streptococcus pneumoniae

(d) Neisseria meningitidis

(e) Haemophilus influenzae

15. All of the following are true about Clostridium tetani, the causative agent of tetanus, EXCEPT:

(a) They are spore-forming rods.

(b) They are part of the normal bowel microflora of horses, cattle, and humans.

(c) They produce a powerful exotoxin that mediates the disease.

(d) Their toxin elicits muscle stiffness, spasms, and paralysis in the victim.

(e) They require oxygen to survive.

16. A vaccine that was developed in 1933 has proven effective in reducing the incidence of disease caused by:

(a) Clostridium botulinum

(b) Mycobacterium leprae

(c) Clostridium tetani

(d) Streptococcus pneumoniae

(e) Listeria monocytogenes

17. The most common form of disease caused by Clostridium botulinum is:

(a) Infant

(b) Wound

(c) Lung, following exposure to aerosols

(d) Foodborne

(e) None of these

18. The endospores of this organism are the most heat-resistant known; it is:

(a) Clostridium tetani

(b) Clostridium botulinum

(c) Mycobacterium leprae

(d) Streptococcus thermicos

(e) Listeria monocytogenes

19. All of the following are true about Clostridium botulinum, the causative agent of botulism, EXCEPT:

(a) Their ability to form toxin depends on infection with a bacteriophage.

(b) They can produce one of eight different toxins, all of which cause human disease.

(c) They produce the most potent toxin known.

(d) Although their endospores are highly heat-resistant, their toxin can be inactivated by only a few minutes' boiling.

(e) All of the above are true.

20. All of the following are true about poliomyelitis EXCEPT:

(a) Most poliovirus infections are inapparent or mild and nonparalytic.

(b) Polio can be caused by three strains of picornaviruses.

(c) The Salk vaccine contains live, attenuated polioviruses while the Sabin vaccine contains formalin-inactivated polioviruses.

(d) Transmission is by the fecal-oral route and pharyngeal secretions.

(e) Poliomyelitis has afflicted man for thousands of years.