lymphatic mastering
Each IgG has ________ binding sites for attachment to antigenic determinants.
2
Which of the following is NOT a step that ultimately leads to antibody production?
Activation of cytotoxic T cells by helper T cells
Which of the following statements is true? a. Memory B cells are typically established when the B cell binds to an antigen. b. Innate defenses are enough to keep a person healthly. c. Adaptive defenses include humoral immunity only. d. Adaptive defenses include both humoral and cellular immunity.
Adaptive defenses include both humoral and cellular immunity.
What is meant by the clonal expansion of a B cell?
An activated B cell divides into cells that give rise to memory B cells and plasma cells
The cells responsible for humoral immunity are the ________ cells.
B
The medulla of a lymph node contains ________ lymphocytes and macrophages.
B
Class I MHC proteins are recognized by which of the following cell types (that are destined to become T cells)?
CD8
What is the role of helper T cells in the adaptive immune response?
Helper T cells activate B cells and cytotoxic T lymphocytes to kill infected host cells
If an infected cell releases antigens into the extracellular fluid, which class of antibodies would be involved in the sensitization process of B cells?
IgD
Immunoglobulins that are found on the surface of B cells and that may activate antibody production are
IgD
________ are clusters of lymphatic nodules deep to the epithelial lining of the small intestine.
Peyer's patches
Which of the following is NOT a step used by cytotoxic T cells to kill infected host cells?
Recognition of infected host cell using its CD4 glycoprotein
If the thymus shrank and stopped making thymosins, we would expect to see an immediate decrease in the number of
T cells
Which of these is NOT a step in antibody-mediated immune defense?
T cells secrete immunoglobulins
Defense of the body against a particular pathogen is provided by
adaptive immunity
The production of autoantibodies generally causes
autoimmune diseases.
When an antigen is bound to a Class I MHC molecule, it can stimulate a ________ cell.
cytotoxic T
Cancer cells would be attacked by which of the following cells?
cytotoxic T cells
CD8 markers are to ________ T cells as CD4 markers are to ________ T cells.
cytotoxic; helper
Where in the lymph node do the T cells first encounter antigens presented by dendritic cells?
deep in the cortex
Antigen-presenting cells located in the epithelia of the skin are called
dendritic cells
In a(n) ________, either the immune system fails to develop normally or the immune response is blocked.
immunodeficiency disease
Another term for antibodies is
immunoglobulins
The first line of cellular defense against pathogens are the
phagocytes
What cells make antibodies?
plasma B cells
The process by which soluble antigens combine with antibodies to form insoluble immune complexes is called
precipitation
All of the following are characteristics of adaptive defenses except a. memory b. tolerance c. specificity d. versatility e. present at birth
present at birth
The release of endogenous pyrogen (or interleukin-1) by active macrophages would
produce a fever
Innate defenses include all of the following EXCEPT __________. a. production of antibodies b. phagocytes c. destruction of abnormal cells by NK cells d. fever
production of antibodies
Helper T cells do all of the following except
provide a rapid response to a future exposure to the antigen
Lymph nodes do all of the following except a. accumulate cancer cells. b. remove excess nutrients from the lymph. c. monitor the contents of lymph. d. remove debris and pathogens from the lymph. e. produce antibodies through B cells.
remove excess nutrients from the lymph
Cytotoxic T cells can attack target cells with which of the following chemical weapons?
secrete a cytokine that triggers apoptosis
When antigens bind to inactive B cells and are brought into the cell by endocytosis to be displayed on the Class II MHC proteins this results in ________ of the B cells.
sensitization
Which is not a way that antigen-antibody complexes may cause elimination of the antigen? a. neutralization b. activation of complement c. opsonization d. enhancing phagocytosis e. sensitization
sensitization
T cells and B cells destroy one antigen without affecting other antigens or normal tissues, this is termed
specificity
In general, lymphocytes
spend most of their time in lymphatic tissue
A crime scene investigator found that a biological fluid sample contains a large amount of IgA-type antibody. This fluid is probably
tears
Which of these statements about lymphocytes is FALSE? a. they mostly occur in lymphoid tissues b. some can produce antibodies c. they are phagocytic d. they occur as B, T, and NK types
they are phagocytic
Most of the lymph returns to the venous circulation by way of the
thoracic duct
There is a decrease in our ability to fight infection as we age. Which lymphoid organ may have a role in this decline?
thymus
Hormones that slow tumor growth are called
tumor necrosis factors
Cancer cells can be detected by NK cells when they show
tumor-specific antigens
Which major class of lymphocytes become cytotoxic T cells?
CD8 cells
An abnormal cell would be identified by the immune system because it showed
Class I MHC proteins with an antigen bound.
Place the following steps of phagocytosis in the order that they occur: 1. Endosome fuses with lysozome 2. Dendritic cell engulfs Rhinovirus 3. Epitopes are attached to MHC-II 4. Digestion of the Rhinovirus 5. MHC-II plus the attached epitope move to the outside of the dendritic cell
2, 1, 4, 3, 5
Correctly order the steps involved cellular immunity: 1. The Tc recognizes the infected host cell 2. The Tc interacts with epitope presented by MHC-I on the dendritic cell 3. The Tc secretes perforin and granzyme, causing apoptosis 4. The helper T cell activates the Tc cell
2, 4, 1, 3
The following are steps in the cell-mediated immune response. What is the correct sequence for these steps? 1. Several cycles of mitosis occur. 2. Antigen is engulfed and presented by a macrophage. 3. Cytotoxic T cells migrate to focus of infection. 4. T cells with specific receptors recognize the antigen. 5. T cells differentiate into cytotoxic T cells or T memory cells. 6. Cytotoxic T cells release perforin and/or lymphotoxin.
2, 4, 1, 5, 3, 6
If the disulfide bonds in IgG were broken, how many peptide chains would be set free?
4
An example of an immunodeficiency disease is __________.
AIDS
Identify the dominant cell type in the cortex of a lymph node cell
B cells
Which pair of molecules do NOT directly interact with one another?
BCR and TCR
Which of the following is true of both lymphatic capillaries and blood capillaries?
Both types are composed of endothelium
Stress suppresses the immune response through the action of __________.
glucocorticoids
The various classes of immunoglobulins are differentiated on the basis of their
heavy-chain constant segments
Cells that help regulate the immune response are ________ cells.
helper T
The human immunodeficiency virus (HIV) that causes the disease known as AIDS selectively infects ________ cells.
helper T
When an antigen is bound to a Class II MHC protein, it can activate a ________ cell.
helper T
Which class of T lymphocyte is killed by the AIDS virus?
helper T
B cells are primarily activated by the activities of
helper T cells
All of the following are characteristics of anaphylaxis except a. sensitized mast cells and basophils are stimulated upon each exposure to an allergen b. helper T cells are destroyed c. symptoms include capillary dilation, airway constriction, pain and itching d. the first exposure does not always lead to a reaction e. IgE antibodies are produced
helper T cells are destroyed
What type of immunity can be transferred by bodily fluids from one person to another, thus conferring immunity to the recipient?
humoral immunity
Milly has just received a kidney transplant and is taking cyclosporin A to help prevent graft rejection. This medication is one in a class of drugs known as ________ drugs.
immunosuppressive
Martha had a heart transplant. In order to keep her body from rejecting the transplant she takes
immunosuppressive drugs
Suppressor T cells act to
inhibit T and B cell activities.
Stress can affect the immune response in all of the following ways except by a. inhibiting glucocorticoid release b. increasing the level of cortisol c. reducing the number of phagocytes d. inhibiting interleukin secretion e. depressing the inflammatory response
inhibiting glucocorticoid release
The effects of activating the complement system include all of the following except a. chemotaxis b. inhibition of the immune response c. opsonization d. stimulation of inflammation e. destruction of target cell plasma membranes
inhibition of the immune response
mmunity that is genetically determined and present at birth is called ________ immunity.
innate
Tears and mucus membranes would be a part of which defense system?
innate external defenses
Which of the following is mismatched? a. innate immunity - NK cells b. adaptive immunity - specific antigens c. innate immunity - physical barrier d. innate immunity - B cells
innate immunity - B cells
Phagocytotic cells such as macrophages identify a variety of enemies by recognizing markers unique to pathogens. They would be classified as which type of defense system?
innate internal defenses
interferons a. bind to viruses and destroy them b. prevent viruses from entering a cell c. reduce macrophage chemotaxis to the infection d. prevent viruses from leaving a cell e. interfere with viral replication
interfere with viral replication
Which type of interferon attracts and stimulates NK cells as a way to enhance viral resistance to viral infection? (Figure 22-12)
interferon alpha
Cytokines that make a cell and its neighbors resistant to virus infection are called
interferons
Which of the following innate internal defenses work by interfering with viral replication?
interferons
Hormones that regulate the activity of B cells and T cells and enhance nonspecific defense are called
interleukins
Infection with the HIV virus occurs through
intimate contact with an infected person's body fluids
Which of the following descriptions is NOT a characteristic of adaptive immunity? a. specificity b. intolerance c. memory d. versatility
intolerance
Which of the following is not a characteristic of AIDS? a. is declining worldwide b. attacked the T helper (CD4) cells c. almost always eventually fatal d. is spread most often through sexual contact e. has killed at least 1/2 million people in the United States
is declining worldwide
A sensitized B cell typically is not activated until
it binds a helper T cell that releases cytokines
All of the following are true of the primary response of humoral immunity except that a. it peaks 1-2 weeks after the initial exposure b. it requires B cell differentiation into plasma cells c. it depends on memory B cells d. circulating antibodies undergo a gradual, sustained rise e. it depends on antigen triggering the appropriate B cell
it depends on memory B cells
physical barriers
keep hazardous organisms and materials outside the body
Lymphatic vessels provide a conduit for metastasizing cancer cells. Ideally, such cells are removed and destroyed by what structure, which thus prevents the spread of cancer?
lymph nodes
An accumulation of lymph in a region where lymphatic drainage has been blocked is called
lymphedema
Which cell type is essential to the immune response?
lymphocytes
Class II MHC molecules are found on which of the following?
lymphocytes and antigen-presenting cells
Which class of cells is particularly abundant in the red pulp of the spleen?
macrophages
Which of the following is not a lymphocyte? a. memory T cells b. plasma cells c. macrophages d. NK cells e. suppressor T cells
macrophages
An inflammatory response is triggered when
mast cells release histamine and heparin
________ cells enable the immune system to respond quickly and robustly if the same antigen is encountered a second time.
memory
The student who caught the cold caused by this specific Rhinovirus was exposed to the exact same Rhinovirus 18 months later. What component of the immune system will protect her from getting the same cold again?
memory B cells
The phagocytic antigen-presenting cells belong to the ________ group.
monocyte-macrophage
Various types of macrophages are derived from
monocytes
Plasma contains ________ special proteins that form the complement system.
more than 30
Immunity that results from exposure to an antigen in the environment is called ________ immunity.
naturally acquired active
Immunity that results from antibodies that pass through the placenta from mother to fetus is called ________ immunity.
naturally acquired passive
Specialized lymphatic capillaries called lacteals are
necessary for the transport of dietary lipids
The process by which antibodies bind to antigenic sites on viruses or toxins, rendering them incapable of binding to other cells, is called
neutralization
During a primary humoral response to antigens all of the following occur except a. neutrophils invade the surrounding areas, releasing chemotactic substances. b. the first immunoglobulins to appear in circulation are of the IgM type. c. B cells may differentiate into plasma cells immediately. d. B cells may undergo several rounds of mitosis before producing plasma cells and memory cells. e. antibody levels do not peak until 1 to 2 weeks after the initial exposure.
neutrophils invade the surrounding areas, releasing chemotactic substances.
An antigen-antibody complex can cause the elimination of an antigen by __________.
opsonization
The process by which the surface of a microorganism is covered with antibodies and complement, rendering it more likely to be phagocytized, is called
opsonization
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 immunization
The cells responsible for the production of circulating immunoglobulins are ________ cells.
plasma
Stem cells that can form all types of lymphocytes are concentrated in the
red bone marrow
Stem cells that will form B cells or NK cells are found only in the
red bone marrow
Lymphocytes a. decrease in number during infection b. respond to antigens c. are actively phagocytic d. destroy red blood cells e. are primarily found in red bone marrow
respond to antigens
Interleukins do all of the following except a. elevate body temperature b. stimulate B-cell activity, plasma cell formation, and antibody production c. stimulate inflammation d. stimulate collagen synthesis e. increase T-cell sensitivity to antigens exposed on macrophage membranes
stimulate collagen synthesis
HIV-infected individuals experience many more opportunistic infections of otherwise nonthreatening microbes because of a severe lack of functioning helper T cells and an associated immunosuppression. Which of the following statements about helper T cells is INCORRECT? a. Helper T cells have CD 4 markers, which are crucial in recognizing infected antigen-presenting cells. b. Helper T cells activate sensitized B cells, which then begin producing and secreting antibodies. c. Helper T cells secrete perforin and lymphotoxins to actively combat infected cells. d. All of the listed statements about helper T cells are correct.
Helper T cells secrete perforin and lymphotoxins to actively combat infected cells
Immunoglobulins that attach to and sensitize mast cells and basophils are
IgE
Which class of immunoglobulins sensitizes cells to allergens?
IgE
Immunoglobulins that are most abundant and are responsible for resistance against many viruses, bacteria, and bacterial toxins are
IgG
Pregnant women are encouraged to get flu shots so that the maternal ________ can pass through the placenta to the fetus.
IgG
immune surveillance
the destruction of abnormal cells by NK cells in peripheral tissues
Anti-A and Anti-B blood typing antibodies are of which class?
IgM
Both ways of inducing active immunity (vaccines and direct environmental exposure to an antigen) will ultimately result in the production of antibodies. Which class of the five classes of antibodies is the first to be secreted during the primary response after the initial exposure to the antigen?
IgM
Immunoglobulins, formed of five subunits, that are the first antibodies to be produced in response to infection, are
IgM
Which class of antibody forms a five-antibody starburst?
IgM
During the primary response, which antibody peaks sooner? During the secondary response, which antibody level is higher? (Figure 22-25)
IgM; IgG
Now that Ruthie has been infected with the chickenpox virus, what is the first step in the immune response that helps her fight off the virus?
the display of antigenic fragments in Class I and II MHC proteins in the plasma membranes of antigen-presenting cells
On what portion of an antigen do the antibodies bind?
the epitope Submit
The cells that perform immunological surveillance are the ________ cells.
NK
After the appearance of bacteria in the body, which immune cell is present for the shortest amount of time? (Figure 22-26)
NK cells
Sally has a tumor. In an effort to fight the cancerous cells her body increases the production of
NK cells
Natural killer (NK) cells __________. a. engage in immunological surveillance b. cause abnormal cells to undergo lysis c. recognize and kill cancer cells d. NK cells perform all of these roles
NK cells perform all of these roles
Which of the following is NOT a characteristic of Natural Killer (NK) cells?
NK cells recognize abnormal or cancer cells by a specific antigen on their cell membrane
Collections of lymphoid tissues, called MALT, are strategically placed throughout the respiratory, digestive, and genitourinary systems. Which one of these is located at the end of the small intestine?
Peyer's patches
Which of the following is not a secondary lymphoid tissue or organ? a. MALT b. thymus c. tonsils d. spleen e. lymph nodes
thymus
T is to ________ as B is to ________.
thymus-dependent; bone marrow-derived
Which of the following statements about lymph flow in a node is false?
The afferent lymphatic enters at the hilum
We study three types of immune disorders: immunodeficiency disorders, autoimmune disorders, and allergies. AIDS is an example of an immunodeficiency disorder. How is it different from a severe allergy or an autoimmune disorder, such as Type 1 diabetes?
The immune system of AIDS patients lacks the necessary coordination between cell-mediated and antibody-mediated immunity and is thus virtually nonfunctional
How do phagocytes recognize foreign cells or bacteria?
The phagocytes recognize molecules on pathogens not normally found on body cells.
Lymphatic organs differ from lymphatic tissues in what way?
They are surrounded by a fibrous capsule and lymphatic tissues are not
What feature do lymphatic vessels share with veins that allows lymph to flow in only one direction? (Figure 22-3)
valves
In IgG, the antigen binding site is formed by the
variable segments of both the light and heavy chains
Autoimmune disorders result from a failure of what property of immunity?
tolerance
________ exists when the immune system does not respond to a particular antigen.
tolerance
An infection and inflammation of the aggregated lymphatic nodules in the pharynx is called
tonsillitis
________ are large lymphatic nodules that are located in the walls of the pharynx.
tonsils
The term lymphadenopathy refers to
a chronic or excessive enlargement of lymph nodes
inflammation
a localized, tissue-level response that tends to limit the spread of an injury or infection
complement
a system of circulating proteins that assist antibodies in the destruction of pathogens
All of the following are true of the thymus gland except that it a. reaches its greatest relative size during the second year of life. b. lies in the anterior mediastinum. c. activates B cells d. .involutes after puberty. e. produces T cells.
activates B cells
Different mechanisms of cytotoxic T cell destruction include all of the following EXCEPT __________. a. stimulating apoptosis b. activation of CD4 marker response to antigen presentation c. disrupting cell metabolism d. secreting perforins
activation of CD4 marker response to antigen presentation
The process by which antibodies bind to the antigen on the surface of cells, forming large immune complexes, is called
agglutination
Which of the following types of cells display protein fragments produced by the cancer within them?
all nucleated cells
Antigens that trigger allergic reactions are called
allergens
Inappropriate or excessive immune responses to antigens are
allergies
Class II MHC proteins are present in the plasma membrane only when
an antigen-presenting cell has engulfed and is processing an antigen. Submit
What is the name of the unique area (specific region) that a lymphocyte recognizes and binds to?
an antigenic determinant
fever
an elevation of body temperature that accelerates tissue metabolism and body defenses
The body's innate defenses include all of the following except a. complement b. antibodies c. inflammation d. the skin e. interferon
antibodies
The complement system works closely with and complements the action of
antibodies
Which of the following can act as opsonins on bacteria, thus enhancing phagocytosis?
antibodies and complement proteins
Newborns gain their immunity initially from
antibodies passed across the placenta from the mother
The human body contains over 75 trillion cells, yet under normal conditions, the T cells only attack specific cells. Which of the following is NOT a trait associated with T cells?
antibody production
A measure of antibody level in the plasma is
antibody titer
A substance that provokes an immune response is called an
antigen
Steps in antigen presentation include which of these? a. antigens are digested b. antigen fragments appear on the antigen-presenting cell's surface c. phagocytic antigen-presenting cells engulf pathogens d. antigen presentation includes all of these steps
antigen presentation includes all of these steps
Class II MHC proteins are found on which of the following cell types?
antigen-presenting cells
The portions of an antigen to which antibodies bind are the
antigenic determinant sites
Immediate hypersensitivity reactions like hay fever may be treated by
antihistamines.
Compared to blood capillaries, lymph capillaries exhibit all of the following except that they
are smaller in diameter
Immunity that results from vaccination against influenza is classified as __________.
artificially acquired active immunity
What type of immunity develops after receiving a vaccine? (Figure 22-17)
artificially acquired active immunity
Frank was bitten by a rattlesnake and received anti-venom containing neutralizing antibodies. Frank received ________ immunity and he ________ long-term immunity as a result.
artificially acquired passive immunity; will not have
Immunizations against infectious diseases are one of the most successful medical advancements in the history of public health. A vaccine, containing weakened or dead forms of the antigen, is administered orally, intranasally, subcutaneously, or intramuscularly. The antigens are not virulent enough to cause the disease, but they provoke the adaptive immune response in the body. A vaccine is an example of which type of adaptive immunity?
artificially induced active immunity
When the immune response mistakenly targets normal body cells and tissues, a(n) ________ develops.
autoimmune disease
In order for a lymphocyte to respond to an antigen, the antigen must
bind to specific receptors on the lymphocyte surface
Which of the following is not a property of an IgG heavy chain?
binds antigen at both ends
in passive immunity, the
body receives antibodies produced by other humans or by an animal
T cells develop from stem cells in the
bone marrow
Which of the following are primary lymphoid organs?
bone marrow and thymus
microphages include
both neutrophils and eosinophils.
If a virus attacks a cell, which type of immunity would be activated?
cell-mediated immunity (cellular immunity)
interferons
chemical messengers that coordinate the defenses against viral infections
The attraction or repulsion of certain cells to chemicals in their environment is called
chemotaxis
Histamine increases blood flow and vascular permeability. This would account for all of the following changes that occur during inflammation except a. redness of the inflamed tissue b. swelling of the inflamed tissue c. movement of defense proteins and cells into the interstitial spaces d. chemotaxis of phagocytes e. heat of the inflamed tissue
chemotaxis of phagocytes
The thoracic duct originates from an expanded chamber called the
cisterna chyli
Which class of MHC proteins presents exogenous antigens?
class II MHC proteins Submit
A person who has AIDS contracts rare and often life-threatening infections because their helper T cell count is so low. Which of the following components of the immune response still respond to antigen despite the low helper T cell count?
clonal selection of B cells
The term immunological ________ refers to the ability to demonstrate an immune response upon exposure to an antigen.
competence
Each of the following is a physical barrier to infection except a. body hair b. basement membranes c. secretions d. epithelium e. complement
complement
Which of the innate defense mechanisms can lyse bacteria and mark cells for phagocytosis?
complement proteins
A ________ antigen is an antigen with at least two antigenic determinant sites.
complete
Lymphatic capillaries are not found in
cornea of the eye
A T cell can only become activated after being physically or chemically stimulated by the abnormal target cell in a process called
costimulation
Lymphocytes that destroy foreign cells or virus-infected cells are ________ cells.
cytotoxic T
The cells directly responsible for cellular immunity are the ________ cells.
cytotoxic T
The lymphocytes that enter tissues and directly attack antigens are __________ cells.
cytotoxic T
The movement of phagocytes through the capillary wall is called
diapedesis
The ________ lymphatics leave the lymph node at the hilum.
efferent
phagocytes
engulf pathogens and cell debris
T cells and B cells can be activated only by
exposure to a specific antigen at a specific site in a plasma membrane
Which one of Ruthie's symptoms is an example of an innate defense mechanism?
fever
In a routine examination, some blood is taken and analyzed. The results show a high IgM titer for the mumps virus but a low IgG anti-mumps titer. This would indicate the person
was recently infected with mumps.
All of the following are true of the secondary response of humoral immunity except that it a. weakens quickly because memory B cells only survive for a year or two b. depends on memory B cells c. results in much higher antibody titers than in the primary response d. results in much quicker rise in antibody titers e. produces more effective antibodies
weakens quickly because memory B cells only survive for a year or two.
Which of the following areas in a secondary lymphoid organ allows intimate contact between blood and the lymphocytes?
white pulp of the spleen