lymphatics
network of vessels beginning in peripheral tissues and ending at
connections to veins
lymph
Interstitial fluid draining into lymphatic capillaries
lymphedema
Condition in which interstitial fluids accumulate and the affected
area gradually becomes swollen and grossly distended
thoracic duct
Large vessel collecting lymph from the body inferior to the diaphragm
and from the left side of the body superior to the diaphragm
cisterna chyli
An expanded, sac-like chamber at the base of the thoracic duct that
receives lymph
antigens
Chemicals, pathogens, proteins, or other foreign substances capable
of inducing the production of antibodies or stimulating an immune
response that ultimately destroys the substance or pathogen associated
with it.
T cell
80 percent of circulating lymphocytes which are responsible for
cell-mediated immunity and for the coordination and regulation of the
immune response
B cell
10 to 15 percent of circulating lymphocytes capable of
differentiating into plasmocytes (plasma cells), which produce antibodies
NK cell
5 to 10 percent of circulating lymphocytes that attack foreign cells,
body cells infected with viruses, and cancer cells that appear in
normal tissues; they continuously monitor peripheral tissues
(immunological surveillance)
tonsils
Large lymphoid nodules in the walls of the pharynx
spleen
Lymphoid organ important for the phagocytosis of red blood cells, the
immune response, and lymphocyte production
immunity
Ability to resist infection and disease, often caused by
microorganisms called pathogens; two forms--nonspecific (innate) and
specific (adaptive)
phagocyte
Cell that engulfs pathogens and cellular debris; the "first line
of cellular defense" against pathogenic invasion
interferon
Chemical messenger that coordinates the defenses against viral infections
complement system
Group of circulating porteins that helps antibodies destroy pathogens
mucosa-associated lymphoid tissue (MALT)
The extensive collection of lymphoid tissues linked with the
epithelia of the digestive, respiratory, urinary, and reproductive tracts
macrophage
Fixed or free phagocytic cell derived from the monocyte of
circulating blood
chemotaxis
Phenomenon of phagocytes being attracted to or repelled by chemicals
in surrounding fluids
diapedesis
Process of phagocytes leaving capillaries by squeezing between
adjacent endothelial cells
immunoglobulins (Igs)
Five classes of circulating antibodies determined by differences in
the structure of heavy-chain constant segments