Ch16 - lymphatic system Flashcards
(25 cards)
Cells of the lymphatic system that are involved in immunity
B cells and T cells
function of lymphatic system
A circulatory system that picks up excess interstitial fluid and returns it to the cardiovascular system, maintaining blood volume and preventing edema
distinguish between thoracic duct and right lymphatic duct
largest vessels of the lymphatic system. Thoracic much larger and longer than the right duct. Thoracic originates in the abdomen as Cisterna Chyli, drains from the intestinal lumbar and intercostal trunks as well as from lower body, left upper limb and left side of the head and neck.
Right Duct originates in the thorax, drains from the right side of the head neck and right upper limb and right thorax.
lymphatic pathway
Lymphatic capillary»_space; Afferent lymphatic vessel»_space; Lymph node»_space; Efferent Lymphatic Vessel»_space; lymphatic trunk»_space; collecting duct»_space; subclavian vein
lymph
tissue fluid. (interstitial fluid) that has ented a lymphatic capillary.
plasma colloid osmotic pressure
capillary blood pressure filters water and mslal molecues from the plasma. plasma proteins are too large to pass through blood capillary walls, creating pressure that helps draw fluid back into the blood capillaries by osmosis
lymph formation
filtration from plasma exceeds resabsorption leading to net formation of
factors that promote lymph flow
valves in the lymphatic vessels, contraction of skeletal muscles that compress the vessels, pressure changes that occur during respiration, smooth muscle contraction in the walls of lymphatic trunks
Consequence of lymphatic obstruction
tissue fluid remains in the interstitial spaces in abnormal amounts, this causes swelling in the area - edema
major functions of lymph
carries pathogenic microorganism and foreign particles to the lymph nodes to be filtered out and acted upon.
also returns excess interstitial fluid and small proteins to blood stream
also plays a role in dietary fat absorption and transportation of fats to the blood stream
mucosa associated lymphoid tissue MALT
unencapsulated diffuse lymphatic tissue scattered throughout the digestive respiratory urinary and reproductive tracts. Lymphatic nodules that make up the tonsils and appendix are also included
lymphatic organs
lymph nodes
thymus
spleen
encapsulated lymphatic tissue
afferent
flows in
efferent
flows out
hilum
the exit from the lymph node
trabeculae
tissue surrounding lymph node surface that extends into the node and partially divides it into compartments.
lymphatic nodule
functional units of the lymph node; masses of lymphocytes (B cells) and macrophages in the cortex. also called lymphatic collicles
lymphatic sinuses
complex network of chambers and channels which the lymph circulates within the node.
macrophages are found within the sinuses
macrophage
large phagocytic cell - it eats things by engulfing them
Locations of lymph nodes
cervical region - drain skin of scalp face nasal and pharynx
axillary region - drain the upper limbs and wall of the thorax, mamary glands upper abdomen
supratrochlear region - medial side of elbow
inguinal region - recieve from lowerlimbs, external genetalia, and lower abdomen
pelvic cavity - receive from pelvic viscera
abdominal cavity - chains along main branches of mesenteric arteries and abdominal aorta
thoracic cavity- in the mediastinum along the trachea and bronchi
lymph node
filters foreign particles from the lymph and produce lymphocytes (Bcells) Also performs immune surveillance in which certain cells in the node monitor the body fluids.
Thymus
produces T lymphocytes (T cells) which provide immunity.
also thymosins which stimulate maturation of T lymphocytes
spleen
largest lymphatic organ - has venous sinuses filed with blood instead of lymph - has macrophages that remove foreign particles, damaged red blood cells, and cellular debris from the blood.
contains lymphocytes; blood reservoir.
lymphatic organs
encapsulate lymphatic tissue:
spleen thymus and lymph nodes
