T-lymphocyte stimulation by specific antigens leads to a type of immunity called
Which of the following cells undergo clonal selection when their antigen receptors bind to an antigen?
CD4 T cells
CD8 T cells
All of the above
The cell that matures in the thymus gland
localizes in the skin tissues.
becomes a plasma cell.
is responsible for cell-mediated immunity.
Which of the following cells has specific antigen receptors, has to interact with antigen presenting cells in order to be activated, and kills host cells that are infected with viruses?
Helper T cells
Cytotoxic T cells
Natural Killer cells
is where lymphoid progenitor cells mature into immunocompetent T cells.
is where B cells mature into plasma cells.
selectively destroys B lymphocytes.
is involved in the humoral immune response.
The site on an antibody molecule that can be bound by a phagocyte is part of the
The portion of the immunoglobulin molecule that contains the antigen binding site can be described as all of the following, except
composed of parts of the light chain and the heavy chain.
is called the Fab fragment.
composed of variable domains.
is called the Fc fragment.
Which of the following are functions of the Fc fragment?
It can combine with phagocytes in opsonization.
It may activate the complement system in resistance mechanisms.
It might attach to certain cells in allergic reactions.
All of the above are correct.
All of the following are true of IgG except
it confers immunity to the fetus.
it is the important factor of the secondary antibody response.
it is the major circulating antibody.
it is critically important in allergic reaction.
The _______ antibody class is referred to as the maternal antibody
The first antibody produced in a primary antibody response is
Which of the following is NOT true about the secondary response to a particular antigen?
Faster than the primary response
. Higher antibody titer than the primary response
Memory cells are involved
Happens the first time the antigen stimulates the lymphocytes
Antibodies can protect against viral infection by binding to epitopes on the viruses which
kills the virus.
prevents the virus from attaching to host cells.
causes agglutination of the viral particles.
None of the above: antibodies offer no protection against viruses.
The neutralization of toxin molecules by antitoxins accomplishes all the following except
increases the activity between toxins and interleukins.
prevents toxin from binding to cells.
prevents toxic effects on cells.
lessens the ability of toxins to diffuse through the tissues.
Antibodies binding to antigens can trigger
activation of complement.
All the above are correct.
Macrophages are involved in
presenting antigen fragments to T cells.
destroying antigen-antibody complexes
Which one of the following is not an effect of complement activation?
Lysis of a bacterial cell through cytoplasmic leakage
Attraction of phagocytes
Enhanced T-lymphocyte activity through thymus gland interaction
Opsonization of bacterial surfaces
CD8 co-receptor proteins are found on
helper T cells.
cytotoxic T cells.
CD4 co-receptor proteins are found on
Which of the following molecules are found on the surface of all nucleated cells in the body?
MHC Class I molecules
MHC Class II molecules
Which of the following molecules are only found on the surface of antigen presenting cells?
Which one of the following is not associated with interleukin-1?
It is secreted by macrophages.
It activates helper T cells.
It stimulates antigen-antibody reactions.
It is produced in response to APC binding to T cell.
. The cells that are responsible for killing abnormal cells such as tumor cells are
Phagocytes such as macrophages.
Helper T cells.
Cytotoxic T lymphocytes.
Cytotoxic T cells release which of the following cytokines in cell to cell combat?
Lysozyme and histamine
Perforin and granzyme
Lysozyme and perforin
Granzyme and histamine
The only cells required in an antibody response to T-independent antigens are
natural killer cells.
antigens that bind directly to MHC protein on T cells.
extraordinarily large antigens on B cells.
haptens + carrier proteins.
None of the above are correct.
With the development of modern vaccines we have brought which of the following diseases to the point where we can now say it has been eradicated?
How does an individual gain naturally acquired active immunity?
Get the disease and recover from it.
Be exposed exposed to the disease, but have a subclinical case.
Be born with a natural immunity to the disease.
Both A and B are correct, but not C.
An individual generally acquires natural active immunity after
an injection of IgG.
an infusion of T lymphocytes.
a blood transfusion.
suffering an illness.
Active immunity develops after the
antigens enter the body and induce an immune response.
antiserum is injected into the body.
antibodies pass across the placenta to the fetus.
antibodies pass in the colostrum to the newborn.
Which of the following types of vaccines induce the strongest immune response, sometimes giving a lifelong immunity?
Live attenuated vaccine
Recombinant subunit vaccine
The intentional injection of an attenuated virus into a person will lead to
naturally acquired active immunity.
artificially acquired active immunity.
naturally acquired passive immunity.
artificially acquired passive immunity.
The Sabin oral polio vaccine is prepared with _______ polioviruses that stimulate the immune system.
. Attenuated viral vaccines are more difficult to use in developing countries than inactivated viral vaccines because
they require more booster shots.
they require refrigeration to retain their effectiveness.
it is difficult finding enough sterile needles for them.
it is difficult finding enough medical personnel to administer the vaccines.
Which of the following is a drawback to the use of inactivated vaccines?
Booster shots are required to maintain immunity for long periods of time.
They have to be kept refrigerated.
They have a short shelf life.
Immunity to the disease _______ may be stimulated by injection of a preparation of _______.
pertussis; attenuated viruses
meningitis; inactivated virus
measles; bacterial fragments
Which of the following is a single-dose vaccine?
Sabin polio vaccine
Diphtheria-tetanus-acellular pertussis (DTaP) vaccine
Salk polio vaccine
All of the above are single-dose vaccines.
Subunit vaccines are those that use
parts of antibody molecules as antigens.
fragments of phagocytes in solution.
parts of microorganisms such as pili and capsular polysaccharides.
preparations of haptens.
Conjugate vaccines contain toxoids because
toxoids are much easier to store.
polysaccharide antigens by themselves produce a weak immune response.
they are only used for diseases caused by toxins
the pathogen that they are designed to protect against has no other antigens.
Which of the following vaccines are conjugate vaccines where part of the capsular polysaccharides are added to a tetanus or diphtheria toxoid?
Recombinant subunit vaccines have been developed against
None of the above is correct.
Passive immunity can
involve an injection of antibodies.
be acquired by a child from its mother.
be administered with a convalescent serum.
A child receiving antibodies in the colostrum during nursing has acquired immunity that is
passive and active.
natural and artificial.
passive and natural.
artificial and passive.
Serum sickness may accompany the development in the body of
the complement cascade
artificial passive immunity.
natural active immunity.
When the immune system recognizes a foreign protein in a serum injection, immune complexes form and complement is activated, a person may develop a type of reaction called
immune complex disease.
Which one of the following is not a characteristic of convalescent serum?
It protects against an illness.
It is derived from the blood of a patient recovering from an illness.
It is used to treat an established disease.
It is made from a pool of sera from animals.
Herd immunity is affected by all the following factors except
immune system strength.
the number of vaccinated people in the population.
Which one of the following is not related to antibody titer?
The amount of antibodies present in the serum
The progress of a disease
The level of immunity in a patient
The degree of activity of T lymphocytes
A neutralization reaction may be observed in the laboratory by
noting the agglutination of red blood cells.
injecting the antigen-antibody mixture to an animal.
watching for precipitate formation.
observing the fixing of complement.
You are carrying out a serological test. You first mix a sample of diphtheria toxin with the patient's serum, inject it into a mouse, then watch to see whether the animal dies or survives. You have performed a(n)
complement fixation test.
Precipitation reactions between antigens and antibodies are characterized by
appearance of IgE in the immune system.
formation of a large lattice formed from antibodies and antigens.
inhibition of the complement system.
destruction of red blood cells.
The zone of equivalence is the
concentrations of antibodies and antigens which is ideal for precipitation.
area on an immunoelectrophoresis gel where the antibody is placed
optimum concentration of vaccine for an individual.
time at which active and passive immunity are equally effective in protecting against disease.
A neutralization test for diphtheria is called
In immunodiffusion, antigens and antibodies diffuse through a gel towards each other and
agglutinate when they reach each other.
neutralize each other.
form a visible precipitate at the zone of equivalence.
fluoresce at the zone of equivalence.
The test to detect Rh antibodies is the
All the following are required to perform a florescent antibody test for syphilis except
a sample of the patient's serum
fluorescein-labeled antiglobulin antibodies.
complement from a guinea pig.
An important advantage of the radioimmunoassay is the
adaptability to small laboratories.
low hazard level.
low cost per test.