Review 4 - Medical Micro
The dots on the map represent reported cases of a disease. This distribution in a(n) ______.
endemic
The conditions known as microbial antagonism may be defined as _____.
an unsuccessful microbial invasion due to the presence of preexisting microbes.
An axenic environment is one _____.
that is free of microbes.
The condition called parasitism is characterized as a(n) _____.
relationship between two organisms where one member harms the other.
Several days after a walk in the woods, Cheryl develops a localized rash. It is not painful and soon fades so she thinks nothing of it. Several months later she experiences increasing fatigue, low-grade fever, and pain in the joints. These symptoms persist for months before she seeks medical attention. This description is most consistent with a(n) _____ infection.
chronic
A new influenza strain appears and is spreading rapidly. What measures might be taken by public heath agencies to stop the spread?
Educate the public, promote vaccination, and treat those who are infected.
Organisms that are resident microbiota are best described as _____.
organisms that remain with the person throughout life.
The taxonomic approach to classifying diseases is based on the
type of microbe that causes the disease.
Microbes know as transient microbiota are
organisms that remain the body for a short time.
A true pathogen may also be described as
highly virulent?????
Which of the following combinations of pathogen and virulence factor is CORRECT?
Streptococcus pyogenes and protein M
Treatment with high doses of antibiotics may lead to which type of health care associated infection?
endogenous infection
Two children attend the same daycare, but one child is at the facility in the morning and the other child attends the facility in the afternoon. Both children have become ill with fifth disease within one day of each other. How might the pathogen have infected both children?
fomite transmission
Which of the following is the correct sequence of a disease process?
incubation, prodromal period, illness, decline, convalescence
The pattern of new cases reported in North America represented in this graph is consistent with ______ transmission.
mosquito vector
Which of the following pairings of microbe and disease was disproven using Koch's postulates?
Haemophilus influenzae and the flu
An example of direct contact transmission is
saliva exchanged during a kiss
What is the relationship between prevalence and incidence for an acute disease like influenza?
the incidence and prevalence are essentially equal
Which of the following types of epidemiology applies to Koch's postulates to study a disease?
experimental
Ten months after the 2010 earthquake in Haiti, there was a sharp increase in the number of cases of cholera. What was the most likely source of the disease?
waterborne
A strain of Neisseria gonorrhea has a mutation which has caused it to lose that ability to produce fimbriae and become less virulent as a consequence. What function has this pathogen lost?
the ability to adhere to cell of the body
The incidence of tuberculosis in the year 2000 in the United States was 12.43/100,000 cases. This means
there were 12.43 new cases of tuberculosis for every 100,000 people in the United States in the year 2000.
In early spring 2009, the CDC reported several dozen cases of novel H1N1 influenza ("swine flu") in the United States. By the summer, the number of confirmed cases was reported as over 40,000. The pattern of novel H1N1 cases in the United States represents a(n) ______ disease.
epidemic
A person is exposed to desert air containing fungus spores and develops valley fever as a result. Valley fever is an example of a ______ disease.
noncommunicable
Which of the following is considered a mechanical vector transmission?
cockroach transmission Shigella
Among the virulence factors produced by Staphylococcus aureus are hemolysin, coagulase, hyaluronidase, and enterotoxin. Which of these factors contribute(s) to the ability of S. aureus to invade the body.
hyaluronidase
Bacterial contaminants grow in food in a closed container. The food is heated after the container is opened, but a person develops food poisoning after eating it. The bacteria were producing
an exotoxin
Which of the following situations might cause normal microbiota to become opportunistic pathogens?
treatment of a cancer patient with radiation
Which of the following situations is NOT a way in which a baby acquires normal microbiota?
microbes cross the placenta during pregnancy
A person licks a needle before injecting a drug into a vein. The person later develops a bacterial infection of the blood. This is an example of
a member of the microbiota gaining access to an unusual location in the body.
Symptoms are
subjective characteristics of a disease that only the patient can feel
Infection occurs when
pathogens enter and multiply in body tissues
All infectious diseases
are caused by microorganisms or their products
Endogenous infectious agents arise from microbes that are
the patient's own normal flora
STORCH is an acronym that represents the most common
infections of the fetus and neonate
A student has their teeth cleaned. The hygienist nicks their gum tissue. The student develops endocarditis due to Streptococcus. What kind of pattern of infection is this?
Focal
A veterinary hospital had an outbreak of Salmonella infantis. Within the facility, how can Salmonella be spread?
All of the choices are correct
Some diseases can be vertically transmitted. That is understood to mean the disease is transmitted
from parent to offspring via milk, ovum, sperm, or placenta
Marion is going to the hospital for a triple bypass operation. She will have general anesthesia, intravenous catheter, surgical wounds, and a urinary catheter. Which nosocomial infection is she at greatest risk for contracting?
urinary tract
Joe contracted Hepatitis A by eating contaminated doughnuts from a local bakery. The source of the disease is ______ and the reservoir is ______.
the doughnut, humans
All of the following are signs of infectious disease, except
nausea
If the ID for gonorrhea is 1,000 cells and the ID for tuberculosis is 10 cells, which organism is more virulent?
Mycobacterium tuberculosis
Which of the following is correct about skatole?
It is a mixture of amines and gases that give feces its characteristic stench.
When would Koch's Postulates be utilized?
To determine the cause of a new disease in a microbiology research lab.
Nosocomial infections involve all of the following, except
they are only transmitted by medical personnel
During what process are hypochlorite and hydrogen peroxide produced to destroy bacteria and inhibit viral replication?
Phagocytosis
Which of the following nonspecific mediators inhibits virus replication and cellular division while increasing some lymphocyte action?
IFN
All of the following are correct about lymph, except
it is transported through the body by the same pump as blood, i.e., the heart
Joan's inflamed and painful joints are likely due to which of the following chemicals?
Prostaglandins
Maria was scratched on her arm by her cat and the site is experiencing rubor. This means
redness
Due to the way the lymph drains from lymph nodes, cell and products of immunity continually
enter the regular circulatory system
All of the following are types of granulocytes because they have prominent cytoplasmic granules when stained, except
Monocytes
Specificity and memory are associated with which body defense mechanism?
T cell and B cell responses
Which is mismatched?
prostaglandins - activate eosinophils and B cells
Which is incorrect about inflammation?
Pyrogens cause vasodilation and increased capillary permeability
All of the following are events of early inflammation, except
macrophages appear first and begin phagocytosis
Which structures are found along lymphatic vessels but are heavily clustered in the armpit, groin, and neck?
Lymph nodes
The reticuloendothelial system
All of the choices are correct.
All of the following pertain to platelets, except
the contain hemoglobin to transport oxygen and carbon dioxide.
Hemopoiesis is the
production of white blood cells, red blood cells, and platelets.
First line of defense may be described as
intact skin, mucous membranes, sebum, tears, and so forth.
The leukocytes called natural killer lymphocytes
are nonspecific leukocytes that secrete toxins onto the surface of virally infected cells.
Structures and products of pathogens that immune cells detect and respond to are called
PAMPs
Which of the following statements is TRUE of eosinophils?
They secrete toxins onto the surface of helminth parasites.
Wandering macrophages recognize microorganisms by means of
both TLR and NOD proteins.
Which of the following leukocyte functions do macrophages carry out?
phagocytosis of pathogens and debris
What feature of the skin creates a physical barrier to microbial invasion?
The outer layers are dead cells, tightly linked together, and are frequently shed.
The process shown in the figure will lead to
vasodilation
Fever is beneficial during viral infection because the higher temperature
increases the effectiveness of interferons.
Which complement protein is the key to activating the alternative pathway of complement activation?
C3
Which of the following substances stimulates the phagocytic activity of phagocytes?
gamma interferons
Which of the following statements regarding phagocyte recognition of pathogens is TRUE?
TLRs in the phagocyte cytoplasmic membrane bind surface structures of microbes.
Which of the following iron-binding proteins is NOT part of the body's iron storage and transport system?
siderophores
In addition to phagocytosis, neutrophils can kill bacteria by producing
both hypochlorite and nitric oxide.
Neutrophils produce ______, which can be triggered by sugar molecules on the surface of microbes to damage the microbes.
????
Receptors known as NOD proteins detect molecules associated with microbes
in the cytoplasm.
Which of the following cells can use nonphagocytic means to kill bacteria?
both eosinophils and neutrophils
Which of the following statements concerning the alternative complement system is TRUE?
Its activation is independent of antibodies
Which of the following is the key difference in the roles of the classical and alternative pathways of the complement system?
the range of microbe types that can be targeted
What is the functions of NK cells?
They identify and poison virus-infected cells.
Mucous membranes are quite thin and fragile. How can such delicate tissue provide defense against microbial invaders?
The mucus physically traps microbes, contains a variety of antimicrobial chemicals, and is shed constantly, along with the outermost layer of cells.
Which of the following is the BEST definition of "microbial antagonism"?
The presence of normal microbiota that protect the body by competing with pathogens in a variety of ways to prevent pathogens from invading the body.
Which of the following contributes to protecting the eyes from microbial invasion?
A mucus layer traps and removes microbes.
Tears contain lysozyme and salt and mechanically flush particles from the eyes.
Tears contain lysozyme and salt.
Tears and mucus combine to trap microbes and remove them.
Tears mechanically flush particles from the eyes.
Tears contain lysozyme and salt and mechanically flush particles from the eyes.
Protection from infection known as species resistance is a result of
both the absence of receptors and lack of suitable environment in the body.
What do the nasal cavity, mouth, and urinary systems have in common?
They are lined with mucous membranes.
The first and second lines of defense against microbial invasion are part of
innate immunity.
Mucus and sweat contain ______ which damage and kill bacteria.
antimicrobial peptides
A CD4+ T cell detects its epitope presented by an APC and receives IL-4 signals. It will differentiate to become a(n)
Th2 cell
How is the development of autoimmunity normally prevented?
T lymphocytes that respond to autoantigens in the thymus undergo clonal deletion.
IgE antibodies are best described as
a cause of basophil and eosinophil degranulation.
Which of the following best describes IgM antibodies?
The are the most common type of antibody in the blood during the initial phases of an immune response.
Vaccination triggers an immune response which produces ______ immunity.
artificial active
Leukocytes migrate to a site of infection in response to
chemokines
What is the result when a dendritic cell phagocytizes a microbe and processes it?
display of epitope - MHC i complexes on the surface of the cell
Which of the following cytokines helps regulate inflammation?
tumor necrosis factor (TNF)
What is the role of interleukins?
signaling between leukocytes
Type 1 helper T (Th1) cells produce ______ to stimulate increased phagocytosis.
gamma interferon
A sick child may have influenza or RSV. These virus infection have different treatment options, so the physician request antibody titer tests. The results are as follows: anti-influenza antibodies are primarily IgM, and anti-RSV antibodies are all IgA and IgG. Which of the following is the most appropriate interpretation?
The child currently has influenza and has previously been exposed to RSV.
What type of immunity is produced by the body when a person contracts a disease?
naturally acquired active immunity
The appendix and the Peyer's patches of the intestines are components of the
MALT (mucosa-associated lymphoid tissue)
The perforin-granzyme pathway involves
the synthesis of special cell-killing proteins that act on infected or abnormal cells.
The protozoan that causes malaria is an intracellular parsite of red blood cells (RBCs). An adaptive immune response to this parasite is problematic because
red blood cells do not produce MHC and therefore do not display the fact that they have been infected by presenting antigens.
Which of the following statements regarding the cell-mediated immune response is TRUE?
A single cytotoxic T lymphocyte can kill many target cells.
After an initial exposure to a pathogen, the phenomenon of ______ produces a faster, more effective response to subsequent exposures.
self-tolerance
Which of the following statements concerning plasma cells is TRUE?
They can produce large quantities of antibodies on a daily basis.
Which of the following recognizes and binds to MHC II antigens and helps stabilize the binding of epitopes to T cell receptors?
CD4
Which of the following molecules would contain T-independent antigens.
polysaccharides
The role of dendrites in the adaptive immune response is to
degrade exogenous antigens for presentation on MHC II molecules.
Which of the following components of antigen processing is MISMATCHED?
endogenous antigen: MHC II
What will be the direct result of the interaction shown in this figure? (This interaction is occurring in a lymph node.)
activation of a helper T lymphocyte
Major histocompatibility antigens are
glycoproteins found in the cytoplasmic membranes of most vertebrate animal cells.
Which of the following cytokines act as a signal between leukocytes?
interleukins
Which of the following statements concerning B cell receptors (BCRs) is FALSE?
They are formed in response to an encounter with an antigen.
Which of the following function(s) in agglutination?
IgA and IgG antibodies
The type of immunoglobulin illustrated here is
IgM
The white blood cells primarily responsible for adaptive immunity are
B lymphocytes and T lymphocytes
You step on something in the yard resulting in a puncture wound that does not bleed freely. Antigens from any microbes that entered the wound will most likely end up in the
lymph nodes of the groin (inguinal)
In what way is the lymphatic system similar to the circulatory system?
the composition of lymphatic fluid is similar to that of blood plasma.
Large accumulations of unactivated self-tolerant lymphocytes conducting surveillance for specific antigenic determinants are found in
the MALT and lymph nodes
Which of the following statements about lymphocytes is FALSE?
B and T lymphocytes can be differentiated under the microscope.
Adaptive immunity is sometimes also called acquired immunity. Which of the following statements provides a basis for the alternative name?
To become activated, lymphocytes require exposure to the antigenic determinant for which they are specific.
Which kind of T cell synthesizes perforins and granzymes to destroy bacteria, viral infected cells, and cancer cells.
TC
Which sequence of events is correct for a specific immune response?
Lymphocyte development, presentation of antigens, B cell challenge, antibody production.
All of the following are characteristics of an effective vaccine except
it should stimulate only the antibody (B-cell) response.
All of the following are advantages of attenuated vaccines over inactivated vaccines except
they can mutate back to a virulent strain.
All of the following are advantages of attenuated vaccines over inactivated vaccines except
they can be transmitted to other people.
Which of the following conditions have been conclusively proven to be linked to childhood vaccinations?
None of the choices are correct
Which of the immunizations would carry the greatest risk for immunocompromised patients?
Attenuated vaccines
The DTaP immunization
All of the choices are correct.
Antitoxins
contain antibodies to neutralize specific toxin.
Variolation involved using
dried, ground smallpox scabs.
Which of the following is a special binding substance that enhances immugenicity and prolongs antigen retention at the injection site?
Adjuvant
Toxoids
contain modified bacterial exotoxin molecules.
Vaccinia virus is often used in the technique to make
"Trojan horse" recombinant vaccine
Acellular vaccines and subunit vaccines
contain select antigenic components of a pathogen rather than whole cells or viruses.
Live, attenuated vaccines
All of the choices are correct.
Killed or inactivated vaccines are prepared by
treatment with formalin, heat, or radiation
High titers of specific antibodies are components of
specific immune globulin (SIG).
Edward Jenner's work involved
immunization using a related, less pathogenic organism to give protection against a more pathogenic one.
Cody is 4 months old and is given a DTaP injection by his pediatrician as part of the routine immunization schedule. What type of immunity will develop as a result of this?
Artificial active immunity.
Sam works in construction and stepped on a sharp nail. He can't remember the last time he had a tetanus shot. What type of immunity is the most important for him to receive?
Artificial passive immunity.
Herceptin is an example of a monoclonal antibody-based drug for
breast cancer
The process of clonal deletion is designed to
destroy clones of lymphocytes able to react to self molecules.
All of the following characterize the secondary response to an antigen except
it mostly IgM antibodies that are produced.
Which type of cell is severely depressed in AIDS patients?
Helper T cells
An example of natural passive immunity would be
a fetus acquiring maternal IgG to the chickenpox virus across the placenta.
An example of artificial passive immunity would be
giving a person immune serum globulins to chickenpox virus after exposure to the disease.
All of the following are characteristics of IgM, except
it is a dimer.
Which process involves antibodies cross-linking cells or particles into large aggregates?
Agglutination
Which process involves antibodies coating microorganisms in order to facilitate phagocytosis?
Opsonization
Which of the following does not belong with transformed cancer cells?
Capacity for limited division
All of the following cells participate in immune surveillance, except
plasma cells.
The heart of a baboon transplanted to a human would be a
xenograft
All of the following are examples of autoimmune diseases, except
Wiskott-Aldrich syndrome.
All of the following are correct about Type O blood, except
persons with this type of blood carry an O antigen on their RBC.
Which of these chemicals is a powerful inflammatory agent that also stimulates uterine contractions?
Prostaglandins
Which of the following is mismatched?
Inhalant - bee sting
What is the Arthus reaction?
An acute response to a second infection of vaccines at the same site.
A xenograft is a tissue exchange
between individuals of different species
Jose needs a kidney due to his diabetes. His sister is a close match and is willing to give him one of hers. What type of transplant is this?
Allograft
Which is incorrect about DiGeorge syndrome?
The major therapy is a bone marrow transplant.
Which of the following can cause secondary acquired immunodeficiencies in T cells and B cells?
All of the choices are correct
A secondary acquired immunodeficiency is
AIDS
Severe combined immunodeficiencies (SCIDs) are due to
a genetic defect in the development of both T cells and B cells
This can be a consequence of a genetic deficiency in B cell survival and maturity
hypogammaglobulinemia
Autoantibodies cause tissue injury in all the following diseases, except
tuberculin reaction
Treatment for agammaglobulinemia is
passive immunotherapy and continuous antibiotic therapy.
Histamine causes of all the following, except
increased sensitivity to light
Which of the following is incorrect about the role of mast cells and basophils in allergies?
They are found mainly in the lymph nodes.
Which is mismatched?
Hay fever - Type 4 hypersensitivity
Erythroblastosis fetalis can be prevented by
injecting the mother with antibodies against the Rh factor late in the pregnancy and after giving birth
The potential for hemolytic disease of the newborn occurs when
fetal Rh+ cells enter an Rh- mother.
A female who is Rh+
is in the majority of the population with regard to Rh status.
A person with O type blood
lacks A and B antigens
Atopy an anaphylaxis are hypersensitivities in the category
Type 1 only.
Tissue samples can be tested for pathogen using ______ assays.
direct fluorescent antibody
Precipitation assays involve the formation of immune complexes with ______ while agglutination tests involve agglutination of ______.
soluble antigens; insoluble antigens
A positive result in a(n) ______ assay results in a line of immune precipitate on an agar plate.
immunodiffusion
Anti-human antibodies (specific for human IgG antibodies) with fluorescent molecules covalently attached are used for
both indirect ELISA and indirect fluorescent antibody tests.
Serologic tests for diagnosis of disease may detect
either antigens or antibodies specific for certain antigens
Which property of antibodies is the basis for complement fixation tests?
The Fc portion can trigger the classical complement system upon antigen binding.
The complement fixation test uses red blood cells as the target for complement activation. Test serum containing antibodies is combined with a known amount of antigen in a tube, and then the RBCs and antibodies against the RBCs are added. A positive result for the complement fixation test would be
a cloudy solution in tube
In precipitation tests, maximum precipitation takes place when
the amount of the antibody and the amount of the antigen are at optimal proportions
Which of the following statements regarding ELISAs is TRUE?
They can be used to detect antibody or antigen.
Viral neutralization testing based on the fact that
viruses introduced into appropriate cell cultures have a cytopathic effect.
Titration is a serological procedure that
determines the amount of an antibody in the blood.
Which type of antibody assay is represented in this figure?
an indirect ELISA
During a visit to a hospital, a child receives the oral polio vaccine. He then returns to his distant village. Sometime later a polio outbreak occurs in the village, but the child and his siblings, who had not had the vaccine, are spared. What is the explanation for this event?
contact immunity
The saliva of a highly venomous reptile is found to contain multiple toxic compounds. What is a practical approach to providing people with protection from the deadly effects of a bite from this reptile?
Prepare antitoxins by immunizing a large animal with the toxins, and use extracted antibodies for treating exposed persons.
An infectious disease researcher isolates the pathogen responsible for an emerging disease. The microbe is grown in the lab for many generations. A preparation of the laboratory-grown microbe is treated with ionizing radiation and then tested for its potential as a vaccine. What type of vaccine is this?
inactivated whole
The figure represents the HIV infection cycle. What virus-specified proteins are required for the events indicated by 1 and 2? (Be sure they are in the correct sequence)
reverse transcriptase, protease
Severe malnutrition may lead to immunodeficiency by
preventing to proliferation B cells
Opportunistic infections typical of AIDS but rare otherwise include
Pneumocystis pneumonia and Kaposi's sarcoma
Antigen-antibody complexes trapped in tissues and triggering complement activation or mast cell degranulation are characteristic of
type III hypersensitivity
Which of the following statements concerning allografts is TRUE?
They induce strong type IV hypersensitivity reactions and must be treated with immunosuppressive drugs.
The disease known as ______ is a disorder in which phagocytes are inefficient at killing bacteria.
chronic granulomatous disease
The name systemic lupus erythematosus refers in part to the distinctive rash resulting from
antibody-antigen complexes accumulating in the skin
A child has a history of repeated severe infections and frequently has recurring infections with the same bacterial pathogen. A blood sample shows some lymphopenia and serological tests are negative. Based on this information, which of the following is the likeliest diagnosis for this child?
Bruton-type agammaglobulinemia
Monoclonal antibodies that bind the IL-2 receptor have been successfully used to reverse graft rejection. Why is this approach effective?
IL-2 stimulates the activity of CTL
A young woman comes into the clinic complaining of itchy, red skin and swelling on her arms and legs. She had not been any parks or wooded areas recently, but she had been shopping. A blood sample reveals elevated levels of granulocytes. What treatment is the physical likely to prescribe at this point?
antihistamines
A small amount of antigen is injected under the skin of a patient. After 30 minutes there is no apparent change at the injection site, but 36 hours later the patient reports that the area is red and swollen. This type of response is due to
type IV hypersensitivity
If circulating immune complexes are deposited in the glomeruli, the ensuing type III hypersensitivity reaction can result in
kidney damage
An agricultural worker experiences difficulty breathing, which becomes progressively worse. Tests show inflammation and damage of the lung tissue, but IgE antibodies and granulocytes are in the normal ranges. With which disorder of the immune system are these signs and symptoms consistent?
type III (immune complex-mediated) hypersensitivity
An accident victim receives a blood transfusion. Shortly thereafter, he begins to have difficulty breathing, develops a fever, and experiences nausea and vomiting. Which of the following is the most likely interpretation of these events?
The blood transfusion was mismatched and the recipient had previously been exposed to the foreign blood group antigens.
How is hemolytic disease of the newborn prevented?
administering anti-Rh IgG late in pregnancy and after pregnancy ends