Name:____________________________
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PATHOPHYSIOLOGY
EXAM 1
Spring 2011
MULTIPLE CHOICE (each correct answer is worth 2pts):
PLEASE READ THE ENTIRE QUESTION AND THEN CIRCLE THE LETTER
NEXT TO THE ONE BEST ANSWER.
1. The body's nonspecific defenses include:
a) skin
b) complement system
c) Acute Inflammatory Response (AIR)
d) all of the above (a, b, and c)
e) a and b
2. Which of the following statements is/are TRUE?
a) Metaplasia involves the replacement of one mature cell type with another mature cell
type that is less differentiated.
b) Dysplasia involves a proliferation of mature cells that are abnormal in size, shape, and
organization.
c) In dysplasia there is uncontrolled cell proliferation.
d) all of the above are true statements
e) Only a and b are true statements
3. Liquefactive necrosis ______.
a) results from the release of hydrolytic enzymes from necrotic cells
b) is the type of necrosis that occurs in neural tissue
c) results from the release of lactic acid from necrotic cells
d) both a and b correctly complete the sentence
e) both b and c correctly complete the sentence
4. Which of the following statements is/are TRUE of free radicals?
a) Free radicals are molecules which have an unpaired electron in one of their orbitals.
b) Superoxide dismutase is an example of a free radical that occurs naturally in
macrophages and may be used to kill pathogens.
c) Antioxidants convert free radicals to less toxic substances.
d) All of the above are true
e) Only a and c are true
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Name:____________________________
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5. In an experimental situation, a respiratory virus is injected into a rabbit and the rabbit is
allowed to make antibodies for the viral antigen. This rabbit is then exposed to a
population of rabbits to allow the pathogen to spread to members of the population. With
regard to the population of rabbits, this would be an example of:
a) innate immunization
b) active immunization
c) passive immunization
d) natural immunization
e) autoimmunization
6. Intracellular deposists of water, lipids, proteins, and/or pigments are examples of:
a) infiltrates
b) exudates
c) chemical injury
d) caseous necrosis
e) none of the above
7. The protein elements of the membrane attack complex are ______.
a) released from mast cells in response to tissue damage
b) synthesized by the liver.
c) secreted by macrophages that are activately phagocytosing pathogens
d) secreted by Tc cells.
e) none of the above
8. Which of the following are characteristically found in chronically inflamed tissue?
a) epitheliod cells
b) fibroblasts
c) lymphocytes
d) all of the above
e) only a and b
9. Coagulative necrosis _______.
a) is a combination of caseous and liquefactive necrosis
b) is most commonly seen in fatty tissues
c) usually results from the release of hydrolytic enzymes that cause proteins to denature
giving the necrotic tissue a white color.
d) none of the above correctly complete the sentence
e) both a and b correctly complete the sentence
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Name:____________________________
Last four digits of Student ID #:______
10. Macrophage chemotactic factor is secreted by:
a) Mast cells
b) Mononcytes
c) Neutrophils
d) B and T cells
e) Eosinophils
11. Steroidal anti-inflammatory drugs (SAIDS), like cortisone, act primarily by ______.
a) blocking the action of bradykinin on pain receptors.
b) Inhibiting the synthesis of prostaglandins, and thereby releaving pain.
c) inhibiting the secretion of interleukin 1 from macrophages, thereby reducing the
accumulation of these cells at the site of inflammation and preventing chronic
inflammation.
d) All of the above
e) Only a and c
12. MHC class I protein complexes are expressed ________.
a) on all cells in the body with a nucleus
b) on macrophages
c) on red blood cells
d) both b and c
13. Which of the following is/are TRUE of interleukin 1 (IL-1)?
a) It is involved in stimulating T helper cells to undergo differentiation and proliferation.
b) It is secreted by TH2 cells and is necessary for B cells to respond to antigen exposure.
c) It stimulates the liver to produce plasma proteins involved in the coagulation, kinin,
and complement systems.
d) All of the above are true of IL-1
e) Only a and c are true of IL-1
14. Which of the following is/are TRUE regarding a paper cut?
a) This type of wound heals by primary intention.
b) This type of wound does not evoke an acute inflammatory response.
c) This type of wound heals by secondary intention.
d) Both a and b are true
e) Both b and c are true
15. NSAIDS, such as aspirin, act by:
a) inhibiting the release of histamine
b) inhibiting the degranulation of mast cells
c) blocking the action of bradykinin
d) all of the above
e) None of the above
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Name:____________________________
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MATCHING: (each correct answer is worth 2pts):
From the list below (a-e), select the word that best matches the numbered item and
place the letter next to the numbered item. Some of the words in the list may not be
used, and some may be used more than once.
a)
IgA
b)
IgD
c)
IgE
d)
IgG
e)
IgM
__D__ 16. Comprise 80% of the free antibodies in the blood plasma .
__C__ 17. Antibodies that cause mast cells to degranulate when they bind antigen.
__A__ 18. Antibodies found in external body secretions.
__E__ 19. These antibodies are known to be responsible for the primary response of B
cells
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TRUE/FALSE. Circle T if the statement is true. Circle F if the statement is false.
For false statements you must cross out the word or words that make the statement
false and replace them with a word or words to make a true statement. You may
not add additional words to the sentence to make it true without crossing out words.
You may not cross out the entire statement in constructing a true statement. (Each is
worth 2 point)
east
Example: T F The sun rises in the west.
B or TH-----------------or----------------------I
T F 20. Cytotoxic T cells are activated by binding to MHC class II- antigen protein complexes.
macrophages chemotactic factor
T F 21. Actively phagocytosing neutrophils secrete leukotrienes.
T F 22. Dysplasia involves a proliferation of mature cells that are abnormal in size, shape, and
organization.
T F 23. A keloid scar is the result of over production of collagen by fibroblasts.
liquefactive
T F 24. Caseous necrosis is a combination of coagulative necrosis and fat necrosis.
T F 25. During the AIR, the overall affect of histamine is vasodilation.
DROP 26. Actively phagocytosing macrophages secrete growth factors that stimulate wound contracture.
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Name:____________________________
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ESSAY/SHORT ANSWER QUESTIONS:
27. Define the following terms: (Each is worth 2 points)
Edema:
Tissue swelling due to the accumulation of extracellular fluid.
Epithelialization:
The re-establishment of the epithelial cell covering over deeper tissues that occurs
duing wound healing.
Bradykinin:
The chemical agent that is the end result of the kinin plasma protein system, acts to
stimulate pain receptors and prolongs the effects of histamine released by mast cells.
Granuloma:
A collagen enclosed mass of chronically inflamed tissue that contains giant
macrophages, fibroblasts, and lymphocytes.
Ischemia:
Insufficient blood flow to tissues that may result in hypoxia and tissue damage
including cell death.
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Name:____________________________
Last four digits of Student ID #:______
28. Compare and contrast wet gangrene, dry gangrene, and gas
gangrene. (Worth 6 points)
Gangrene result from the necrosis of large groups of cells or
tissues. There are three types of gangrene , wet gangrene, dry gangrene,
and gas gangrene. In wet gangrenous tissue liquefactive necrosis occurs,
in which the necrotic cells release hydrolytic enzymes that digest the
surrounding tissues. It results from the interruption of the venous blood
flow out of the necrotic tissue. Wet gangrenous tissue appears moist,
black in color, and typically has a bad odor as a result of bacterial
infection. In dry gangrene the tissue undergoes coagulative necrosis, in
which the necrotic cells release lactic acid that denatures the proteins
being released from the lysing cells. It is caused by the interruption of
arterial blood flow to the tissue. Dry gangrenous tissue appears dark
brown or black in color and is very dry. Gas gangrene results from
invasion of necrotic tissue by one of the strains of the anaerobic
Clostridium bacteria. This bacteria produces enzymes that destroy
connective tissues and cell membranes producing hydrogen sulfide gas
that bubbles out of the necrotic tissue.
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Name:____________________________
Last four digits of Student ID #:______
29. Three types of hyperplasia were discussed in lecture (this does not include
atypical hyperplasia). Describe and give an example of each type of hyperplasia.
(worth 6 points)
The three types of hyperplasia are compensatory, hormonal, and
pathologic. In compensatory hyperplasia, cell proliferation occurs in
response to repeated damage or removal tissue. An example of
compensatory hyperplasia is the formation of callus on the hands or
feet in response to normal wear and tear of daily work activities.
Hormonal hyperplasia is cell proliferation in response to stimulation by
a hormone. An example is the normal proliferation of the endometrium
that occurs in the uterus as a result of the monthly estrogen cycle.
Pathologic hyperplasia is abnormal cell proliferation caused by
excessive hormonal stimulation. An example is seen if there is
oversecretion of estrogen. The oversecretion of estrogen causes
excessive hyperplasia of the endometrium, which results in excessive
bleeding during menses.
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Name:____________________________
Last four digits of Student ID #:______
30. Answer one (A or B) of the following: (3 extra credit points if you answer both
questions completely correct, no partial extra credit will be given. If you answer
both A and B, circle the letter of the question you want used as your primary
answer.)
A) Name and describe the three phases of wound healing. Include in your essay the
terms: fibroblast, macrophage, growth factors, angiogenesis, collagen, granulation
tissue, epithelialization, myofibroblast, wound contraction. (Worth 6 points)
Or
B) Describe the main events that lead to cell death following hypoxic injury to a cell,
indicating particularly which of the events are reversible and which are irreversible.
(Worth 6 points).
A) During the AIR, the most important cells with regard to wound healing are the
macrophages. At the site of tissue damage the macrophages secrete growth factors
that stimulate epithelial cell division, angiogenesis, and fibroblast chemotactic
factor. The fibroblast chemotactic factor attracts fibroblasts to the site of tissue
damage. These fibroblasts play the key role in the subsequent two phases of wound
healing.
During the reconstructive phase, fibroblasts secrete collagen that forms a
framework that replaces lost tissue. The fibroblasts and collagen together form what
is called granulation tissue or scar tissue. The angiogenesis that was initiated during
the AIR results in capillaries growing into the scar tissue giving it a pinkish color.
As the reconstructive phase progresses some of the fibroblasts differentiate into
myofibroblasts that have the ability to contract, much like muscle cells. The
contraction of the myofibroblast results in wound contracture in which the edges of
the wound are pulled together. Also during this phase, epithelialization occurs in
which the epithelial cells at the margins of the wound divide and spread under the
blood clot that covers the surface of the wound, re-establishing the epithelial lining
and sealing the deeper tissues from the environment.
During the maturation phase, the scar tissue that was formed during the
reconstructive phase is remodeled giving it increased tensile strength. The
capillaries that were established during the reconstructive phase degenerate leaving
an avasuclar scar tissue.
B) Cell death from hypoxia results from two causes:
Anaerobic metabolism---> increased lactic acid---> pH decreases-lysosomal
swelling and damage to membrane---> release of hydrolytic enzymes----> Death
Anaerobic metabolism--->decreased ATP production--->decreased function and
eventual failure of Na+/K+ and Na+/Ca++ pumps--->Disruption of ionic gradients for
Na+ and Ca++--->Na+ and Ca++ buildup inside cell disrupting osmotic gradient---
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>Water enters cell down osmotic gradient causing swelling--->swelling of cell
membrane disrupts normal selective permeability of the membrane further
disrupting normal gradients and allowing cell proteins and enzymes to leak out-->mitochondrial swelling and swelling of endoplasmic reticulum which causes
ribosomes to fall off, causes disruption of normal respiration and protein synthesis--> Death
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Name:____________________________
Last four digits of Student ID #:______
31. Starting with degranulation of mast cells, describe the acute
inflammatory response to tissue damage. In your essay you must correctly
use the terms: mast cells, NCF, ECF-A, MCF, histamine, leukotrienes,
macrophages, neutrophils, interleukin-1, plasma protein systems,
bradykinin, membrane attack complex (Worth 12 pts)
The acute inflammatory response is triggered by tissue damage resulting in
the release of histamine from mast cells in the tissue, this is referred to as
degranulation of the mast cells. The released histamine causes vasodilation
increasing blood flow to the tissue causing it to become red and increasing the
temperature of the tissue. Histamine also increases the permeability of the
capillaries in the inflammed tissue allowing plasma and blood cells to leak into the
tissue. The leakeage of plasma causes the tissue to swell (edema). In addition to the
release of histamine, additional chemical signals are released from mast cells, these
include the leukotrienes, prostaglandins, neutrophil chemotactic factor (NCF), and
eosinophil chemotactic factor (ECF-A). Leukotrienes have similar affects as
histamine in that they cause vasodilation and increased capillary permeability.
Leukotrienes also act as a chemotactic agent for neutrophils and eosinophils,
drawing these cells to the site of inflammation. The neutrophils are the first
phagocytic cells to arrive at the site of inflammation. They begin the initial attack on
invading pathogens and also begin cleaning up cellular debris. Eosinophils release
chemical agents, such as histaminase, that control the acute inflammatory response,
preventing an over-response. Eosinophils are also the main defense against parasites
that my attempt to gain access to the body through the damaged tissue. The leakage
of plasma proteins into the inflammed tissue activates the plasma protein systems,
which include the kinin system, complement system, and the clotting system. The
kinin system is a casacade that lead to the synthesis of bradykinin. Bradykinin acts
along with prostaglandins to stimulate pain receptors, it also has similar effects to
histamine except that it is longer lasting and so may be responsible for prolonging
the inflammatory response. The complement system is responsible for producing
membrane attack complex that inserts pores into the cell membrane of invading
pathogens causing them to swell and eventually burst. Some of the intermediates of
the complement cascade also have chemotactic properties that attract neutrophils to
the site of inflammation. The clotting system produces a network of fibrin fibers
that prevent blood loss, and also serve to keep pathogens and the cells that fight the
pathogens localized to the site of inflammation. The neutrophils that begin the
initial phagocytosis of invading pathogens release macrophage attracting factor
(MCF) that draws macrophages to the site. The macrophages are large, long lived
phagocytositic cells capable of phagocytosing thousands of pathogens before they
die. Actively phagocytosing macrophages release Interleukin-1 (IL-1), which has
systemic inflammatory effects. Systemically, IL-1 acts on the hypothalamus to reset
the body's temperature center resulting in fever. It also stimulates the liver to
synthesize and release plasma proteins. It also stimulates the maturation and release
of neutrophils from the bone marrow. In severe inflammation, the increased levels
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of IL-1 can lead to the release of premature neutrophils, called band cells. The
presence of band cells in the blood is indicative of a severe inflammation somewhere
in the body.
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Name:____________________________
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32. Discuss the roles and interactions of each of the following in the
immune response to a bacterial infection: macrophages, IL-1, IL-2, IL4, B cells, cytotoxic T cells, helper T cells, TH1 and TH2 cells, IgM and
IgG, MHC class I and class II antigen-protein complexes, CD4, CD8.
(Worth 8 points)
Macrophages are the primary antigen presenting cells. After
phagocytosing and digesting pathogen, the macrophages complex
antigens from the pathogen with MHC class 1 and 2 proteins and
express them on their cell membrane. The MHC class 2 protein-antigen
complexes are responsible for activating mature helper T cells. The
helper T cells bind to the MHC class 2-antigen complex with their T cell
receptor. The CD4 protein helps the T helper cell to bind by binding to
the MHC class 2 protein. The macrophage also releases IL-1, which
stimulates the helper T cell to respond to the binding of antigen by
differentiating and proliferating into activated helper T cells and
memory helper T cells. The activated helper T cells release IL-2, which
stimulates them to differentiate and proliferate into TH1 and TH2 cells.
The TH1 cells release IL-2, which stimulates mature cytotoxic T cells to
proliferate and differentiate into plasma cytotoxic T cells and memory
cytotoxic T cells. In order to respond to the IL-2, the cytotoxic T cell
must first have been presented with antigen by cells expressing MHC
class 1-antigen complex. The CD8 protein helps the cytotoxic T cell
bind to antigen by binding to the MHC class 1 proteins. The plasma
cytotoxic T cells attack infected cells, releasing toxins that kill the
infected cell. The TH2 cells secrete IL-4 that stimulates B cells that have
been activated by binding antigen with IgM expressed on their cell
surface, to proliferate and differentiate into plasma B cells and memory
B cells. The plasma B cells secrete IgG that fights the invading
pathogen.
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