ch 22 - lymphatic Flashcards
lymphatic system
Cell tissues and organs responsible for defending the body from environmental hazards and internal threats
immune system
all body cells and tissues are involved in immunity, including parts of the lymphatic, integumentary, skeletal, cardiovascular, respiratory, and digestive systems
immunity
the ability to resist infection and disease
pathogens
organisms that cause disease, such as viruses, bacteria, fungi and parasites
lymph
fluid similar to plasma but w/o plasma proteins
lymphatic vessels
carry lymph from peripheral tissues to veins
lymphoid tissues
Connective tissues dominated by lymphocytes
lymphoid organs
organs where lymphocytes may form, mature or become activated
lymphoid organs ex
lymph nodes, thymus, spleen
lymphatic vessels
carry lymph from peripheral tissues to the venous system
meningeal lymphatics
vessels found in dura mater that drains CSF to cervical lymph nodes, remove waste
Lymphatic capillaries
smallest lymphatic vessels, present at almost every tissue of the body
lymphedema
Obstruction of lymphatic vessels that prevent lymph drainage
superficial lymphatics
vessels in the subcutaneous layer, areolar layer of mucous membranes
deep lymphatics
larger vessels that accompany arteries and veins
superficial and deep lymphatics converge to form large lymphatic trunks that emoty into 2 major collecting vessels:
thoracic duct
right lymphatic duct
thoracic duct
collects lymph from all body regions below the diaphragm and left side of the body above the diaphragm
right lymphatic duct
collects lymph from right side of body superior to the diaphragm
lymphocytes
immune system cells that respond to specific invading pathogens
examples of lymphocytes
T cells
B cells
NK cells
lymphatic nodules
areolar tissue densely packed w/ lymphocytes
germinal center
central zone of the nodule which contains dividing lymphocytes
tonsils
large lymphoid nodules in the wall of the pharynx
pharyngeal tonsil
in the posterior wall of the nasopharynx
L + R palatine tonsils
at the posterior inferior margin of the oral cavity
lingual tonsils
deep to the pithelium, covering base of the tongue
tonsilitis
inflamamtion of tonsils, esp palatine
Mucosa-associated lymphoid tissue (MALT)
lymphoid tissues associated w/ the mucosa of the digestive, respiratory, urinary, and reproductive systems
Aggregated lymphoid nodules
Clusters of lymphoid nodules deep to intestinal epithelial lining
lymph nodes
small lymphoid organs found along lymphatic vessels
trabeculae
bundles of collagen fibers that extend from capsule into the interior of the lymph node
hilum
shallow indentation where blood vessels and nerves reach the lymph node
afferent lymphatics
carry lymph from peripheral tissues TO the lymph node
efferent lymphatics
carry lymph AWAY from the lymph node
cortex of lymphoid
outer region that contains B cells within germinal centers
paracortex of lymphoid
contains mostly T cells
medulla of lymphoid
inner region organzied into medullary cords
lymphadenopathy
refers to disease of the lymph nodes
each lobe of the thymus has
outer coretx of epithelial reticualr cells
inner emdulla of epithelial reticular cells in concentric layers called thymic (Hassall;s) corpuscles
epithelal reticular cells function
maintain blood thymus barrier
spleen
large lymphoid organ lateral to the stomach by the gastrosplenic ligament
spleen function
filters blod
stores iron
immune response to antigens
pulps of the spleen
red pulo contains RBCs
white pulp resembles lymphoid nodules
