Chapter 20 - Mastering A&P
Fever is the maintenance of body temperature higher than
37.2 C & 99 F
The cells responsible for antibody-mediated immunity are the _______ cells
B
The medullary sinus of a lymph node contains _______ lymphocytes and plasma cells
B
The body's nonspecific defenses include all of the following except
B and T cells
T cells release cytokines to stimulate the activation of
B cells
Which lympocytes are responsible for antibody-mediated immunity?
B cells
When an antigen is bound to a Class II MHC protein, it can activate a ________ cell
CD4 T
_______ cells provide cell-mediated immunity
CD8 T
Lymphatic vessels are located in almost all portions of the body except
CNS
Immunoglobulins that primarily found in glandular secretions such as mucus, saliva, and tears are
IgA
Immunoglobulins that are found on the surface of B cells and may activate antibody production are
IgD
Immunoglobulins that attach to and sensitize mast cells and basophils are
IgE
Immunoglobulins that are most abundant and are responsible for resistance against many viruses, bacteria, and bacterial toxins are
IgG
Immunoglobulins, formed of five subunits, which are the first antibodies to be produced in response to infection are
IgM
Which is true regarding the thymus?
It produces several hormones that are important to the development of functional T cells
What is the final step in the path of blood flow through the spleen?
blood collects into small veins that merge to form trabecular veins
Complement:
is a system of circulating proteins that assists antibodies in the destruction of pathogens
Which leukocytes are abundant, mobile, and quick to phagocytize cellular debris or invading bacteria?
neutrophils
Which mechanism results in a coating of antibodies and complement proteins that increases the effectiveness of phagocytosis?
opsonization
Lymphocytes production involves
[all of the above] - bone marrow - thymus tissues - peripheral lymphoid tissues
In general, lymphocytes
[all of the above] - spend most of their time in lymphoid tissue - have one nucleus - have relatively long life spans
All of the following are true of the thymus gland except that it
activates B cells
Cytotoxic T cells attack target cells by doing what
activating genes that trigger apoptosis
The process nu which antibodies bind to the antigen on the surface of cells, forming large immune complexes, is called
agglutination
Lymphocytes that destroy foreign cells or virus-infected cells are _______ cells
cytotoxic T
Which of the following statements regarding lymph is false
lacteals are prominent lymphatic vessels in the cardiopulmonary system
The white pulp of the spleen is populated by
lymphocytes
_______ cells enable the immune system to respond quickly and robustly if the same antigen is encountered a second time
memory
The first line of cellular defense against pathogens are the
phagocytes
Lymphocytes
response to antigens
Lymph draining from your right shoulder flows into
right lymphatic duct
A crime scene investigator found that a biological fluid sample contains a large amount of IgA-type antibody. This fluid is probably
tears
Lymphocytes are produced and stored in all of the following except
the brain
The merging of _________ forms the right lymphatic duct
the right jugular, right subclavian, and right bronchomediastinal trunks
The lymphatic system is composed of all of the following except
the venae cavae
Which characteristic of lymphatic capillaries is correct?
they originate as pockets rather than forming continuous tubes
Most of the lymph returns to the venous circulation by way of the
thoracic duct
The thymus produces several complementary hormones called
thymosins
Stem cells that will form T cells develop in the
thymus
________ are large lymphoid nodules that are located in the walls of the pharynx
tonsils
Areas of the spleen that contain large aggregations of lymphocytes are known as
white pulp
Which lymphocytes migrate throughout the body, moving through peripheral tissues in search of abnormal cells?
NK cells
The cell that dominates the deep cortical region of a lymph nodes is the ______ cell
T
The cells directly for cell-mediated immunity are the ______ cells
T
Adaptive immunity is the result of the actions of
T and B cells
_______ will develop when the immune response mistakenly targets normal body cells and tissues
autoimmune disorders
The primary function of the lymphatic system is
defending the body against both environmental hazards and internal threats
Helper T cells do all of the following except
destroy target cells using perforins
The movement of phagocytes through the capillary wall is called
diapedesis
Autoantibodies are
directed against the body's own antigens
The various classes of immunoglobulins are differentiated on the basis of their
heavy-chain constant segments
Cells that help regulate the antibody-mediated immune response are _______ cells
helper T
The human immunodeficiency virus (HIV), which causes the disease known as AIDS, selectively infects _________ cells
helper T
B cells are primarily activated by the activities of
helper T cells
Suppressor T cells act to
inhibit T and B cell activities
Immunity that is genetically determined and present at birth is called _________ immunity
innate
Infection with the HIV virus occurs through
intimate contact with an infected person's body fluids
During a primary response to antigen exposure, all of the following occur except
neutrophils invade the surrounding areas, releasing chemotactic substances
Which lymph node structure(s) contain(s) B cells within germinal centers that resemble those of lymphoid nodules?
outer cortex
Which lymp node structure is dominated by T cells?
paracortex
In an experimental situation, a rabbit is exposed to a viral antigen to which it makes antibodies. These antibodies are then purified and injected into a human with the same viral disease. This is an example of
passive immunity
The cells responsible for producing antibody molecules are _______ cells
plasma
In response to tissue damage and infection, circulating proteins called pyrogens
produce a fever
Lymph nodes do all of the following except
remove excess nutrients from the lymph
The thoracic duct drains lymph from all of the following regions except the
right breast
B cells prepare for activation by presenting an antigen bound to Class II MHC proteins in a process called
sensitization
The lobules of the thymus are divided by partitions called
septa
Defense of the body against a particular pathogen is provided by
specific immunity
The largest single collection of lymphoid tissue in the adult body is located in the
spleen
The site on an antibody that is specifically tailored to fit a specific antigen called the
variable segment
All of the following are true of the secondary response to antigen exposure except that it
weakens quickly because memory B cells only survive for a year or two
The lymphocytes are most important in
fighting infection
Which class of leukocytes is particularly abundant in the red pulp of the spleen
free and fixed macrophages
If the thymus shrank and stopped functioning properly, we would expect to see an immediate decrease in the number of
T cells
Which cells are responsible for cell-mediated immunity
T cells
The binding of an antigen to an antibody can result in
all of the above - agglutination or precipitation - neutralization of the antigen - complement activation and opsonization
The role of antigen-presenting cells in immunity is to
all of the above - activate T cells - display antigen fragments - process antigens
Inflammation produces localized
all of the above - heat - swelling - pain - redness
Nonspecific defenses include
all of the above - physical barries - phagocytic cells - interferons - inflammation
Examples of physical barries against pathogens include
all of the above - sebaceous glands - epithelia - epidurmal layers - mucus
Characteristics of specific defenses include
all of the above - versatility - tolerance - memory - specificity
A substance that provokes an immune response is called an
antigen
n antibody binds to an antigen at a specific area called the
antigenic determinant site
Compared to blood capillaries, lymph capillaries exhibit all of the following, except that they
are smaller in diameter
Which of the following concerning Class I MHC proteins is false?
bind complement
Lymphatic vessels commonly occur in association with
blood vessels
In passive immunity, the
body receives antibodies produced by other humans or by an animal
The attraction of repulsion of certain cells to chemicals in their environment is called
chemotaxis
Histamine increases blood flow and vascular permeability. This would account of all of the following changes that occur during inflammation except
chemotaxis of phagocytes
The thoracic duct originates from an expanded chamber called the
cisterna chyli
Which is an expanded, saclike chamber that receives lymph from the inferior part of the abdomen, the pelvis, and the lower limbs?
cisterna chyli
Each of the following is a physical barrier to infection except
complement
Before specific defenses are activated, most antigens must
either infect cells or be processed by a phagocyte
After puberty, the thymus gradually shrinks and becomes more fibrous, in a process called
involution
A sample of John's blood shows a high level of pyrogens. This would indicate that John
is running a fever
All of the following are true of the primary response to antigen exposure except that
it is delayed by the memory cell stage
Class II MHC molecules are found only on which of the following?
lymphocytes and antigen-presenting cells
Antibodies may bind to superficial sites on bacteria or other toxins, making the toxin incapable of attaching itself to a cell. This mechanism is known as
neutralization
An inflammatory response is triggered when
mast cells release histamine and heparin
Various types of macrophages are derived from
monocytes
Immunity that results from exposure to an antigen in the environment is called _______ immunity
naturally acquired active
Immunity that results from antibodies that pass the placenta from mother to fetus is called _________ immunity
naturally acquired passive
T is to __________ as B is to
thymus-dependent; bone marrow-derived
A test to measure the antibody level a blood sample is called an
titer
_______ exists when the immune system does not respond to a particular antigen
tolerance
