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Microbiology Exam #4
May 12, 2008
Name:____________________________________
Matching (22 pts)
Match the complement protein/fragment with its description.
____ C3b
A. Cleaves C5
____ C5a
B. Anaphylatoxin – recruits PMNs to the site of infection.
____ C5b6789
C. Opsonin – facilitates opsonization
____ C3 Convertase
D. Membrane attack complex
____ C5 Convertase
E. Produces fragments C3a and C3b
Match the immunoglobulin class with its description.
____ IgG
A. Most efficient immunoglobulin for stimulating complement.
____ IgM
B. Commonly found in the mucous membranes.
____ IgA
C. Most common immunoglobulin class in the bloodstream.
Match the term below with the most appropriate definition.
____ Epidemic
A. Constant incidence of disease in a specific area.
____ Pandemic
B. Global increase in incidence of a disease.
____ Endemic
C. Localized increase in incidence of a disease.
Multiple Choice (34 pts)
Select the ONE best answer
____ Which of the following antibody/antigen based techniques would provide the most rapid
diagnosis?
A.
B.
C.
D.
Microtiter dish ELISA assay
Western Blot assay
Agglutination assay
Polymerase Chain Reaction
____ A factor that has allowed new diseases to emerge and old ones to re-emerge is
A.
B.
C.
D.
E.
homeless shelters.
overuse or incorrect use of antibiotics.
cancer chemotherapy.
international travel.
All of the above have contributed.
____ Vaccines are successful in preventing disease due to
A. the production of large quantities of antibodies that remain in the bloodstream and
attach to subsequent invading microbes.
B. production of long-lived "memory" cells that can quickly respond to invading microbes.
C. production of additional neutrophils that can seek out and destroy invading microbes.
D. production of more complement proteins that can increase the bodies response to
subsequent invading microbes
____ Which of the following STDs can be treated and cured?
A.
B.
C.
D.
E.
Gonorrhoea
HIV
Herpes
none of the above
all of the above
____ Bacterial STDs are viewed as primarily a social problem rather than a health problem
because
A.
B.
C.
D.
E.
bacterial STDs are not as common as viral STDs.
bacterial STDs are not lethal.
bacterial STDs are treatable and preventable.
bacterial STDs are only a concern in third-world countries.
None of the above
____ A problem with the eradication of many infectious diseases is that
A.
B.
C.
D.
E.
diseases can have reservoirs other than humans.
vaccines are ineffective in many parts of the world.
vaccines are only effective against viral diseases
people misuse antibiotics leading to antibiotic resistant organisms.
All of the above
____ Exotoxins
A.
B.
C.
D.
are generally proteins.
are weakly immunogenic.
cause fever.
are much alike chemically.
____ Removing most of the microorganisms from the respiratory tract would
A.
B.
C.
D.
lead to better health.
have no effect on health.
lead to disease.
improve digestion.
____ The classical complement cascade begins when _______ is present.
A.
B.
C.
D.
antibody
antigen/antibody complex
a bacterium
C3b
____ A virus infected cell might be destroyed by
A.
B.
C.
D.
mast cells.
+
CD4 helper T cells.
+
CD8 cytotoxic T cells.
a memory cell.
____ PMN or neutrophils
A.
B.
C.
D.
E.
contain lysozomes.
can phagocytose.
migrate from blood to sites of infection.
arrive at infection sites before monocytes.
All of the above
____ The endosymbionts that enable Riftia to survive in the harsh environment around
hydrothermal vents are found in the
A.
B.
C.
D.
the gills
the plume
the sheath
the trophosome
____ Buchnera aphidicola is a bacterial endosymbiont of aphids. It provides the aphid with
amino acids such as tryptophan. How does B. aphidicola manage to by-pass the feedback
inhibition that normally prevents overproduction of amino acids?
A. The amino acid biosynthetic genes are present on a multicopy plasmid
B. They produce a modified form of tryptophan that can be used by the aphid but does not
feedback inhibit biosynthesis.
C. They no longer have the genes that repress tryptophan biosythesis.
D. They are located in specialized cells called bacteriocytes.
____ A ruminant can survive on cellulosic material because
A.
B.
C.
D.
bacteria aid in digestion.
it releases sugars from the material.
it uses methane as a hydrogen sink.
it produces amylase.
____ What is the purpose of inflamation?
A. Seal lacerations and plug broken blood vessels
B. Remove damaged cells and repair damaged tissue.
C. Restrain the population growth rate of pathogens by killing them or creating conditions
that limit their replication
D. All of the above
____ Which of the following is an example of a specific host defense?
A.
B.
C.
D.
Skin
Antibody
Tissue specificity
Cilia
____ Which part of an antibody is responsible for its specificity for a particular epitope?
A.
B.
C.
D.
E.
Fab
Fc
J chain
H chain
L chain
Short Answer (26 pts)
What is a toxoid?
Name two properties that distinguish endotoxins from exotoxins.
How do phagocytes such as PMNs destroy bacteria?
What are 2 roles for our natural microbiota?
Why are babies susceptible to infant botulism from eating honey but most adults are not?
How do the bacterial populations of the stomach and large intestine differ qualitatively and
quantitatively?
Name two advantages of automated diagnostic equipment such as the Vitek system.
Describe two reasons why nosocomial infections occur.
What is herd immunity?
What one thing about microbes that you learned in this class impressed you the most?
Short Essay (18 pts)
Answer 3 of the 4 questions below. 6 pts each.
6 bonus points possible for answering all 4.
Describe the steps leading to inflammation and the function of inflammation in host defenses.
Do you think anti-inflammatory medications help or hinder our defenses? Why or why not?
Describe how either an ELISA or agglutination assay is done. Compare the strengths and
weaknesses of each. Explain situations in which you might choose one technique over the other
in diagnosing an infectious disease.
Describe, in general terms, how the public health system works. Include the responsibilities of
physicians, local, state and national public health agencies. What impact do these agencies have
on the spread of infectious disease. Do you think they are doing an adequate job? Why or why
not?
Write as much as you can about a topic you studied extensively for this exam but you felt was not
covered sufficiently on this exam.