WITH RATIONALES GUARANTEED PASS
In which structure does B lymphocytes mature and undergo changes that commit them to
becoming B cells?
Thymus gland Regional
lymph nodes Bone
marrow
Spleen - ANSWER- ANS: C
RATIONALE: B lymphocytes mature and become B cells in specialized (primary) lymphoid
organs—the thymus gland for T cells and the bone marrow for B cells.
Neither regional lymph nodes nor the spleen are involved in changing B lymphocytes into B
cells.
An individual's acquired immunity is dependent on the function of which cells? (Select all that
apply.)
T lymphocytes B
lymphocytes
Macrophages
Opsonins
Neutrophils - ANSWER- ANS: A, B, C
RATIONALE: T lymphocytes, B lymphocytes, macrophages, and dendritic cells are involved in
acquired immunity. Opsonins are molecules that tag microorganisms for destruction by cells of
the inflammatory system; these cells are primarily neutrophils. Neutrophils are white blood cells.
The common hay fever allergy is expressed through a reaction that is mediated by which class of
immunoglobulins?
IgE
IgG
IgM
,T cells - ANSWER- ANS: A
RATIONALE: Type I reactions are mediated by antigen-specific IgE and the products of tissue
mast cells. The most common allergies (e.g., pollen allergies) are type I reactions. In addition,
most type I reactions occur against environmental antigens and are therefore allergic. Hay fever
allergy is not mediated by IgG, IgM, or T cells.
During an IgE-mediated hypersensitivity reaction, which leukocyte is activated?
a. Neutrophils
b. Monocytes
c. Eosinophils
d. T lymphocytes - ANSWER- ANS: C
RATIONALE: Of the options provided, only eosinophils are activated during IgE- mediated
hypersensitivity reactions.
During an IgE-mediated hypersensitivity reaction, what causes bronchospasm?
a. Bronchial edema caused by the chemotactic factor of anaphylaxis
b. Bronchial edema caused by binding of the cytotropic antibody
c. Smooth muscle contraction caused by histamine bound to H1 receptors
d. Smooth muscle contraction caused by histamine bound to H2 receptors - ANSWER-
ANS: C
RATIONALE: During an IgE-mediated hypersensitivity reaction, smooth muscle contraction
caused by histamine bound to H1 receptors results in bronchospasms. The bronchospasm is not
caused by edema or by histamine binding to H2 receptors.
A patient is having an IgE-mediated hypersensitivity reaction. What action by the healthcare
professional is best?
a. Give the patient an antihistamine.
b. Prepare to give the patient a blood transfusion.
c. Ask the patient is he/she is having pain at the site.
d. Apply warm, moist heat to the affected area. - ANSWER- ANS: A RATIONALE:
Histamine is the most potent mediator in an IgE-mediated hypersensitivity reaction (Type
1). Histamine bound to H2 results in the degranulation of mast cells with the release of
histamine. Blocking histamine receptors with antihistamines can control some type I
,responses. The healthcare professional would not need to give the patient blood; warm;
moist heat; or ask about pain.
A student asks about the mechanism that results in type II hypersensitivity reactions. What
description by the professor is best?
a. Antibodies coat mast cells by binding to receptors that signal its degranulation, followed by
a discharge of preformed mediators.
b. Antibodies bind to soluble antigens that were released into body fluids, and the immune
complexes are then deposited in the tissues.
c. Cytotoxic T lymphocytes or lymphokine-producing helper T 1 cells directly attack
and destroy cellular targets.
d. Antibodies bind to the antigens on the cell surface. - ANSWER- ANS: D RATIONALE:
The mechanism that results in a type II hypersensitivity reaction begins with antibody binding
to tissue-specific antigens or antigens that have attached to particular tissues. The cell can be
destroyed by antibody IgG or IgM and activation of the complement cascade through the
classical pathway.
How are target cells destroyed in a type II hypersensitivity reaction?
a. Tissue damage from mast cell degranulation
b. Antigen-antibody complexes deposited in vessel walls
c. Cytotoxic T lymphocytes attack the cell directly.
d. Natural killer cells - ANSWER- ANS: D
RATIONALE: The mechanism that results in a type II hypersensitivity reaction involves a
subpopulation of cytotoxic cells that are not antigen specific (natural killer [NK] cells).
Antibody on the target cell is recognized by Fc receptors on the NK cells, which releases toxic
substances that destroy the target cell. Tissue damage from mast cell degranulation occurs in
type I hypersensitivity reactions. Antigen-antibody complexes are active in type III
hypersensitivity responses.
Cytotoxic lymphocytes are involved in type IV hypersensitivity responses.
Graves disease (hyperthyroidism) is an example of which type II hypersensitivity reaction?
a. Modulation
b. Antibody-dependent cell-mediated cytotoxicity
c. Neutrophil-mediated damage
, d. Complement-mediated lysis - ANSWER- ANS: A
RATIONALE: The antibody reacts with the receptors on the target cell surface and modulates
the function of the receptor by preventing interactions with their normal ligands, replacing the
ligand and inappropriately stimulating the receptor or destroying the receptor. For example, in
the hyperthyroidism (excessive thyroid activity) of Graves disease, autoantibody binds to and
activates receptors for thyroid-stimulating hormone (TSH) (a pituitary hormone that controls the
production of the hormone thyroxine by the thyroid). Graves disease is not a result of cell-
mediated cytotoxicity, neutrophil-mediated damage, or complement- mediated lysis.
Immunoglobulin E (IgE) is associated with which type of hypersensitivity reaction? a. I
b. II c. III d. IV - ANSWER- ANS: A
RATIONALE: Hypersensitivity reactions have been divided into four distinct types: type I
(IgE-mediated) hypersensitivity reactions, type II (tissue-specific) hypersensitivity reactions,
type III (immune complex-mediated) hypersensitivity reactions, and type IV (cell-mediated)
hypersensitivity reactions.
A Rh-negative woman gave birth to a Rh-positive baby. When discussing Rho[D]
immunoglobulin with her, what information should the healthcare professional provide?
It provides protection against infection from poor immunity in the baby. It prevents
alloimmunity and hemolytic anemia of the newborn.
It provides necessary antibodies in case the mother doesn't breastfeed.
It causes the intestinal tract of the newborn to produce antibodies. - ANSWER- ANS: B
RATIONALE: Alloimmunity occurs when an individual's immune system reacts against
antigens on the tissues of other members of the same species. This can occur when a woman is
Rh-negative and gives birth to an Rh-positive baby, leading to hemolytic anemia of the
newborn. Rho[D] immunoglobulin does not provide protection against infection, provide
antibodies to a bottle-fed baby, or cause the intestine to produce antibodies.
Which mother does the healthcare professional prepare to administer Rh immune globulin (Rho-
GAM) to?
a. Is Rh-positive and the fetus is Rh-negative
b. Is Rh-negative and the fetus is Rh-positive
c. Has type A blood and the fetus has type O