Ch. 22 Homework
The cells directly responsible for cellular immunity are the ____ cells
B
In order for a lymphocyte to respond to an antigen, the antigen must
bind to specific receptors on the lymphocyte surface
Each is a physical barrier to infection
body hair epithelium secretions basement membranes
Stem cells that will form B cells or NK cells are found only in the
bone marrow
Microphages include
both neutrophils and eosinophils
The primary function of the lymphoid system is
defending the body against both environmental hazards and internal threats
Stress can affect the immune response by
depressing inflammatory response reducing the number of phagocytes inhibiting interleukin secretion increasing the level of glucocorticoids
In passive immunization,
either body receives antibodies produced by other humans or body receives antibodies produced by an animal
T cells and B cells can be activated only by
exposure to specific antigen at a specific site in a plasma membrane
Compared to blood capillaries, lymph capillaries exhibit
have no basement membrane are larger in diameter have walls of endothelial cells that overlap like shingles are frequently irregular in shape
Immunity that is genetically determined and present at birth is called _____ immunity
innate
A sample of John's blood shows a high level of pyrogens. This would indicate that John
is running a fever
The lymphoid system is composed of
lymphatic vessels the spleen lymph nodes lymph
Specific defenses depend on the activities of
lymphocytes
An inflammatory response is triggered when
mast cells release histamine and heparin
Immunity that results form exposure to an antigen in the environment is called _____ immunity
naturally acquired active
Immunity that results from exposure to an antigen in the environment is called _____ immunity
naturally acquired active
Immunity that results form antibodies that pass the placenta from mother to fetus is called ____ immunity
naturally acquired passive
The cells responsible for the production of circulating immunoglobulins are ____ cells
plasma
All of the following are true of the thymus gland
reaches its greatest relative size during the second year of life involutes after puberty produces T cells lies in the anterior mediastinum
Histamine increases blood flow and vascular permeability. This would account for
redness of the inflamed tissue heat of the inflamed tissue movement of defense proteins and cells into the interstitial space swelling of the inflamed tissue
Examples of physical barriers against pathogens include
sebaceous glands mucus epithelia epidermal layers
The body's nonspecific defenses include
skin complement interferon inflammation phagocytic cells physical barriers
The largest collection of lymphoid tissue in the body is found in the
spleen
Inflammation produces localized
swelling redness heat pain
A crime scene investigator found that a biological fluid sample contains a large amount of IgA-type antibody. This fluid is probably
tears
Leslie has had sore throat and the lymph glands in her neck are swollen. This would indicate that
the affected lymph glands contain an increased number of lymphocytes
Characteristics of specific defenses include
versatility tolerance memory specificity
_____ are antigen-presenting cells located in the epithelia of the skin
Dendritic cells
The only antibodies that normally cross the placenta are
IgG
_____ is the class of antibody first secreted in response to a new antigen
IgM
During a primary immune response, the
IgM titer is initially higher than the IgG titer
____ are fixed macrophages found in the liver
Kupffer cells
______ are fixed macrophages that are found in the central nervous system
Microglia
The cells that perform immunological surveillance are the ____ cells
NK
_____ are antibodies that make it easier for phagocytes to engulf their target cells
Opsonins
_____ are clusters of lymphoid nodules deep to the epithelial lining of the small intestine
Peyer patches
If the thymus shrank and stopped making thymosins, we would expect to see an immediate decrease in the number of
T cells
Inappropriate or excessive immune responses to antigens are
allergies
Newborns gain their immunity initially from
antibodies passed across the placenta from the mother
Autoantibodies
are directed against the body's own antigens
Lymphatic vessels are located in almost all portion of the body, except the
CNS
______ are large lymphoid nodules that are located in the walls of the pharynx
Tonsils
Helper T cells
Trigger B-cell division, plasma cell maturation, and antibody production Enhance production of memory and cytotoxic T cells Attract and stimulate the activity of NK cells Enhance nonspecific defenses
The term lymphadenopathy refers to
a chronic or excessive enlargement of lymph nodes