Microbiology Exam 4 (chapter 14, 15, and 16)
Hyaluronidase and collagenase both allow bacteria to
invade a host's tissues
what will happen if an animal raised in axenic environment is exposed to a pathogenic microbe late in life
the animal will exhibit a very poor immune response to the pathogens
If a person turns their ankle, how would one determine if damage to the tissue in the ankle has occurred
the ankle is red, swollen, and warm to the touch
which of the following most accurately describes how a pathogenic bacterium might be affected by antibodies
the antibodies may block proteins necessary for binding the pathogen to the host, may opsonize the bacterium, or may agglutinate bacteria
Where are the complement proteins found in the body
the blood serum
Antibodies from cellular immune responses are used in
the classical pathway
which of the complement pathways was discovered first
the classical pathway
What is hemolysis
the destruction of RBC
Expected prevalence of a disease is
the expected occurrence of a disease based on past observations
In the last segment of the animation, how many regions of the world experience the pandemic during April of year four
Five
which of the following statements is true regarding hand washing
Frequent and proper hand washing should be routinely done by patients and by healthcare workers, both prior to and after interaction
What does the plasma membrane of a phagocyte attach to on a microorganism
Glycoproteins
Which molecule triggers apoptosis
Granzyme
Attenuated virus vaccines can be produced by which of the following processes
Growth in tissue culture cells for many generations
Immune cells that secrete cytokines and activate other immune cells are
Helper T-cells
How do helper T-cells and Cytotoxic T-cells work together?
Helper T-cells produce cytokines to activate other cells of the immune system
What is urticaria
Hives
What is the reservoir for this disease organism, Salmonella enterica serotype Typhi?
Human
Humans have species of resistance to feline immunodeficiency virus for which of the following reasons
Human cells do not have the chemical receptors required for attachment by feline immunodeficiency virus
Antibodies are a part of which type of immunity
Humoral
Which part of the adaptive immune response involves B cells
Humoral
What combination of mother/child blood types might develop into hemolytic disease of the newborn
If the mother is Rh- and the fetus is Rh+, this may lead to hemolytic disease of the newborn
What is the fate of activated cytotoxic t cells
They proliferate into a clone of cells specific to the same antigen; some of these cells then differentiate into long-lived memory t cells, while others mature to attack infected cells
How can surgeons help to limit nosocomial infections
They should perform surgeries and invasive procedures only when necessary
Clonal deletion occurs in the
Thymus
What is the role of epidemiology
To learn how to treat and prevent various disease
Tom has a genetic disorder in which he does not synthesize class 1 MHC proteins or functional NK cells. Which of the following statements would be true for Tom
Tom would not be able to destroy virally-infected cells
How should you describe this skin reaction to the bee sting
Type 1 hypersensitivity
If a T cell recognizes MHC in conjunction with autoantigens, it will either _____ or differentiate to become a regulatory T cell
Undergo apoptosis
How was this carrier identified?
Urine culture
Which of the following best describes why West Nile Virus is considered to be an emerging infectious disease?
West Nile Virus outbreaks have increased in numbers and affected areas since 1937
What features of West Nile virus make it an emerging disease of special concern?
West Nile virus is an arthropod-bourn virus transmitted by mosquitoes West Nile virus has a high mortality rate in immunosuppressed humans and infects many species of birds in southern Europe, the Mediterranean basin, and North America West Nile virus is maintained in nature through biological transmission between susceptible hosts by blood-feeding arthropods
When would endotoxins be released from a bacterial cell
When the cell dies
If a new bacterial pathogen entered a human body through an accidental needle stick, the first cell that would try to kill the pathogen would likely be
a phagocyte
Which of the complement pathways employs properdin
alternative pathway
which of the following are phagocytic cells descended form monocytes
alveolar macrophages and microglial cells
The figure represents a petri dish with a fungus, shown in darker grey, growing in the midst of bacterial lawn, shown in light gray. The relationship between the fungus and the bacteria would best be described as
amensal
All of the following might lead to a disease caused by an opportunistic pathogen except
an encounter with an infected animal
Which of the following would be considered a fomite?
an infected toy
The release of lipid A may lead to
Fever, blooding clotting, inflammation, and shock
Which of the following would be the first sign of infection that resulted in the release of endotoxin
Fever
This nurse's condition worsened after medical treatment. Which specific medication immunosuppressive?
Aerosol corticosteroids
When do helper T-cells develop into Th 1 or Th 2 cells
After proliferation into a clonal population
Approximately how many days is IgG present in the serum
10 days
Based on the data supplied, what was the approximate mortality rate for this outbreak?
14%
What effect might a buildup of bilirubin have on a fetus
A build of bilirubin may lead to severe neurological damage or death
Which of the following would be considered a vector
A fly carrying disease from fecal matter to food
Some bacteria secrete chemicals that prevent the phagocytic digestion of a bacterium by interfering with the fusion of ________ to the phagosomes
A lysosome
The primary immune response involves
A slow rise in the concentration of antibodies, followed by a gradual decline
Most human pathogens are weak outside of the body and die in a hostile environment. They survive outside the body only in areas that accommodate their survival needs. Pneumonia is a disease of the lungs. What is the most likely mode of transmission for pneumonia pathogens?
Airborne
During his research of West Nile Virus, Bill learned that this Virus is placed within a functional grouping known as arboviruses. What is meant by the term arbovirus
An arbovirus is an arthropod-borne virus An arbovirus is maintained in nature through biological transmission
Why might a transfusion of Rh+ blood cells into an Rh- individual be dangerous
An individual with Rh- type blood will produce antibodies against the Rh+ blood cells
What type of epidemiological study is exemplified in this case
Analytical
This child has had a moderate reaction to his first bee sting. If he were to be stung again, the signs and symptoms could be sever and life-threatening due to constricting of airways. What is this systemic reaction called, and what would the treatment of choice be
Anaphylaxis and epinephrine
An anamnestic response is
Another name for secondary response
When are anti-Rh antibodies developed by the adaptive immune system
Anti- Rh antibodies are produced after exposure to the Rh antigen
A response that is uniquely directed against pathogenic Bordetella pertussis would involve what component?
Antibodies
Which cells possess MHC class 2 proteins
Antigen-presenting cells
Which of the following OTC medications would provide the best relief of symptoms
Antihistamines
Th 2 cells produce cytokines that activate
B cells
Which vaccination may cause a false positive skin test for TB
BCG vaccine
What is the function of the CD8 receptor
Bind to MHC molecules
The bacterium S. Aureus is commonly found in the nasal cavity of healthy people. If inhaled into the lungs, however, it may cause pneumonia. S. Aureus is best described as
Both resident microbiota and opportunistic pathogens
Based on the animation, which of the following is cleaved by C1
C2 and C4
Based on the animation, which of the following is responsible for cleaving C3
C2aC4b
Histamines are released when mast cells are exposed to ____ which are fragments of complement proteins
C3a and C5a
in the classical pathway, which of the following directly activates cellular responses
C3a, C5a, and C5bC6C7
Based on the animation, which of the complement proteins can directly bind to the surface of a bacterial cell
C3b
which complement protein is used as an opsonin
C3b
Which event happens first during cytotoxic T-cell activation
CD8 binds to MHC molecules of infected cells
Virulence factors allow microbes to be pathogens. This means that a bacterium with more virulence factors _____.
Can more easily infect hosts and cause disease
The process by which phagocyte moves toward a chemical signal at the site of an infection is called
Chemotaxis
what complement result involves the use of phagocytes
Chemotaxis and opsonization
Which of the following would you likely see on the surface of a human dendritic cell following phagocytosis of a bacterium
Class 1 MHC with dendritic cell antigens and Class 2 MHC with engulfed bacteria
What would a virally infected skin epithelial cell have on its cell surface
Class 1 MHC with liver cell antigens
What purpose does clonal deletion serve
Clonal deletion destroys T cells with receptors complementary to the body's normal autoantigens
When aerosols containing pathogens spread disease from a distance of less than one meter, it is considered
Contact transmission
Which of the following is considered a major category of transmission of disease
Contact, vehicle, and vector transmission
If a person could not form C2, which result of complement would be affected
Cytolysis, chemotaxis, inflammation, and opsonization
Which type of cell directly attacks infected cells
Cytotoxic T-cells
HIV directly infests T-cells. Why is this problematic for cell-mediated immunity
Cytotoxic T-cells begin to attack the virally infected T-cells, reducing the number of T-cells in the body
Which of the following are likely to be found on an MHC-1 protein
Damaged mitochondrial fragment
What day does IgM first appear
Day 5
Leukocytes have the ability to cross the vessel wall out of the blood stream and into the tissues. This process is known as _____
Diapedesis
When does MHC-2 loading occur?
During the fusion of vesicles containing MHC-2 proteins with vesicles containing digested pathogens
In which location within the cell are epitopes bound to MHC class 1 proteins
ER
What makes agglutination by antibodies possible
Each antibody has at least 2 antigen-binding sites
How could this epidemic be stopped without firing the worker?
Educate the worker about personal hygiene and use of an outhouse or designated bathroom. Instruct him to thoroughly wash his hands with clean soap and water after using the facilities.
The brain tissue in the birds indicated the possibility of encephalitis. What is encephalitis, and why should this type of infection cause concern among health care professionals?
Encephalitis is an inflammation of the brain tissue. It is a concern to health care professionals because an infection in the brain means the virus has breached protective measures.
If a disease occurs at a fairly stable rate, it is said to be
Endemic
Which type of toxin, when secreted, may lead to the disruption of the cells within the gastrointestinal tract?
Enterotoxin
How would you classify this abrupt jump in cases of legionellosis in Louisiana
Epidemic
Toxins and bacterial parts are considered ___ antigen because they are present outside of the body's cells
Exogenous
Thymus cells are specialized to participate in clonal deletion because they have the ability to
Express all of the body's autoantigens
Match the key terms with their descriptions
Includes cilia, mucous membranes, dendritic cells: Innate Immunity Immunological response brought about by antibody production: Humoral Immunity Immunological response that kills infected host cells: Cellular immunity Use BCRs to recognize epitope. First step in clonal selection: Immature B cells Phagocytes that engulf anything foreign. Eventually display epitope to helper T cells using MHC 1&2: Dendritic Cells Lymphocytes that activate B cells and CTL's: Th Cells Differentiated B cells that are stored in lymph nodes to provide protection against future infections by the same pathogens: Plasma Cells Kills infected host cells: Cytotoxic T cells
What do we call the person determined to be the first case of a disease in an outbreak
Index case
Why is vasodilation important to tissue repair
It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage
Why is a release of endotoxin into the bloodstream potentially deadly?
It can lower blood pressure and cause the patient to go into shock
In the last segment of the animation, when does the first epidemic occur?
January of year three
An inflammatory response would result from which of the following
Jellyfish sting
Which of the following is the best mode of controlling the spread of West Nile infections?
Limit exposure to mosquitoes to prevent the transmission of West Nile virus.
Endotoxins are also known as
Lipid A
While investigating a newly discovered G- bacterium, you find that when the bacteria die, the host experiences severe fever and inflammation. You suspect that the bacterium has _____ in its outer wall membrane
Lipid A
T cells recognize epitopes only when they are bound to
MHC
Which proteins on the antigen-presenting call are recognized by the helper T-cell
MHC proteins
Which of the following cells is included as an antigen-presenting cell
Macrophages
What is the standard for TB surveillance in a hospital
Mantoux skin test required annually
Which cells are involved in a secondary response
Memory B cells and plasma cells
E. Coli living in the colon of a human is an example of a ... relationship
Mutualism
Why must physicians wait three months to skin test the babies and their mothers?
Mycobacterium TB is a slow-growing organism, and it takes the body time to mount a cell-mediated defense that can be detected by the skin test
What are the clinical signs and symptoms of typhoid fever?
Nausea and headache?
Is legionellosis contagious?
No
If a person lacked the ability to form C5, what direct result of complement could still occur
Opsonization
Which organism is responsible for the degradation of exogenous antigen within an antigen-presenting cell
Phagolysosome
Which structure do antigen presenting cells utilize to directly help them present bacterial antigens
Phagolysosome
Why would bleeding time be increased in this patient?
Platelet count is decreased
Apoptosis is the process of
Programmed cell death
Why did the skin turn red and swell up
Redness and swelling are due to the release of histamines during degranulation of mast cells and basophils
How does RhoGAM prevent hemolytic disease of the newborn
RhoGAM attaches to Rh antigen, leading to its removal before the mother's immune system mounts an adaptive response
There are four categories typically used to describe the occurrence of a disease. According to the data, 33 people in this one community were infected within a single week. Which category describes the occurrence of this disease?
Sporadic
In the thymus, T cells randomly generate different _____ with a particular shape
T cell receptors
Which receptor on the helper t-cell recognizes the specific antigen from an antigen presenting cell
TCR
Natural killer cells are activated by
Th 1
In the sixth segment of the animation, why is the disease epidemic in North America
The disease occurs at a higher rate than what would normally be expected in this region
Which organelle assists directly with the presentation of MHC-1 antigens
The endoplasmic reticulum
When might Rh antigens form the fetus be introduced into the mother's blood stream
The mother may be exposed during labor or delivery
Which is an example of vehicle disease transmission
The presence of Listeria on undercooked chicken served for dinner
Which of the following was the defining test that determined that this nurse has an active case of TB
The presence of acid-fast bacilli in the sputum sample
What is apoptosis
The process of programmed cell death
How is the secondary response different from the primary response in terms of antibody concentration in the blood
The secondary response is faster and produces more antibodies than the primary response
Increased permeability of the vessels leads to _____ and pain
edema
If mosquitoes are the mode of transmission for West Nile Virus, why did the students in Bill's virology class focus on finding the virus in the dead birds rather than collecting mosquitoes to examine?
The students tried to isolate the West Nile Virus from birds because they are an amplifying host for the virus, making it more likely that the virus can be isolated from these animals.
There are five sequential stages of disease that are shared among most infectious diseases. Match the disease stage with its definition.
The time between infection and occurrence of the first symptoms is termed the incubation period. A time of mild generalized symptoms occurring before more serious symptoms is called the prodromal period. The most severe stage of disease with serious symptoms and/or signs occurs during the illness. The body gradually returns to normal as symptoms begin to subside during the decline. The body recovers from the disease and returns to normal during the convalescence.
Which of the following are functions of lectins
They act as opsonins for phagocytosis, they attach to carbs on some bacterial and viral surfaces, and they activate C2 and C4
What direct effect do histamines and leukotrienes have on capillaries
They allow capillary walls to open and become leaky
First line defenses have what aspect in common with each other
They are physical barriers against invading pathogens
In reference to clonal deletion, what the clones
They are the offspring or potential offspring of lymphocytes
Alpha and beta interferons
are produced by infected fibroblasts and macrophages
what type of infections or immune reactions will the patient need to worry about until his CBC return to normal
bacterial infections
Why may some bacteria use extracellular enzymes to form blood clots
blood clot can hide bacteria from the immune system
What is the most expedient way to increase the blood cell and platelet counts of this right now
blood transfusion
When mast cells degranulate and release histamine, which of the following events may occur
both bronchial spasms and increased mucus productions
The complement cascade and its by-products contribute to
both triggering inflammation and attracting phagocytes to sites of infection
the process of blood clotting leads to the formation of ____ a potent mediator of inflammation
bradykinin
All of the following are ways that neutrophils can directly or indirectly kill cells except
by forming MAC's
which of the following can release histamines
cells from damaged tissues and the complement pathway
Pus is comprised of
dead phagocytes
What does anemia mean
decreased red blood cell numbers
Acute and chronic inflammations differ in that acute inflammation
develops quickly, ends quickly, and is typically beneficial
Which of the following phagocytic processes occurs last in the sequence
exocytosis
How does cytolysis occur via the complement pathway
formation of the MAC in invading cells, killing them
Most often, antigens are composed of
glycoproteins
The destruction of blood cells leads to the release of large amounts of ______, which is then degraded into bilirubin
hemoglobin
Fever is beneficial during viral infection because the higher temperature
increases the effectiveness of interferons
The process of diapedesis is important because ____
it allows white blood cells to leave the vessel system and attack pathogens in the tissues
Why is the alternative pathway of complement useful in the early stages of an infection
it does not rely on activation by antibodies
Rabies is an example of zoonosis that is hard to control because ____
its reservoir contains both domestic and sylvatic animals
White blood cells known as _______ are the main cells involved in the third line of defense
lymphocytes
Which of the cells listed below can present antigens on class 2 MHC proteins
macrophages
Basophils, platelets, and _____ are all capable of secreting histamines
mast cells
Which of the following is not an example of symbiosis
microbes crossing the placenta to the fetus
Where are MHC molecules located on a cell
on the surface of the cell
What aspect of this patient's immune function would be most directly impacted by this condition
phagocytosis
A major difference between exotoxins and endotoxins is that endotoxins are
physically part of the bacterial structure
What is the role of plasma cells in humoral immunity
plasma cells produce antibodies
Bacterial capsules work by
protecting the bacterium form engulfment
What cellular macromolecules make up the complement pathway
proteins
Which of the following groupings contain things that are all true indicators of inflammation?
redness, heat, edema, pain
The health of the patient
should be the primary concern of the healthcare worker
Which of the following characteristics of a catheter should be considered, to help minimize the spread of nosocomial infections
single-use
If a microbe were capable of preventing a phagosome from fusing with a lysosome, which of the following would occur
the microbe would survive inside the phagocyte
Emigration is
the migration of phagocytes through blood vessels to the site of tissue damage
Both the innate and adaptive defenses of the immune system work to prevent
the penetration and colonization by pathogens, and the diseases they cause
What is a phagolysosome
the structure that results from the fusion of a phagosome and a lysosome
What additional information would you request from those who survived the disease
their height and whether or not the mister were on when they shopped the produce aisle
What is a feature of the small fragments presented by MHC-1 proteins
they are small peptides, roughly 8-10 amino acids long
Which of the following statements about eosinophil function is correct
they attach to the surface of parasitic helminths and produce toxins that kill the parasite
What is the role of opsonins
they create "handles" that make it easier for the pseudopods of phagocytes to attach to the microbe invader
If a patient notices a healthcare worker not following suggested precautions
they should immediately bring it to the attention of the healthcare worker
what is the function of inflammation in response to a burn from a hot iron
to repair the damage tissue
Which of the following situations might cause normal microbiota to became opportunistic pathogens
treatment of a cancer patient with radiation
Inflammatory mediators such as bradykinin and histamine cause blood vessels to
vasodilate
Epidemiology is defined as the study of
where and when a disease occurs, and how it is transmitted
