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