lymphatic system Flashcards
how does lymph travel
arterial blood–>capillaries—>lymphatic capillaries–>vessels–>nodules (follicles)–>lymphatic trunks and then duct–>venous system
what portion of blood travels through lymph
15% of interstitial fluids (capillaries) is picked up by the vessels and eventually returned to sinuses, the rest goes directly into venules
functions of lymphatic system
- picks up debris and waste
- LDL transport from GI (picked up by lymphatic capillaries)
- directly involved in immune function
which is the last part of the lymphatic system before fluid is drained back into venous circulation
lymphatic trunk
lymphatic nodules
- aggregates of cells with connective tissue capsule surrounding it
- 1mm-2cm, formed in groups that accompany major veins of the body (and are so named)
- lymph enters afferent vessels on convex side and flows b/t sinuses, where it is exposed to immune response if needed
- lymph exits through efferent vessels at the hilum
where is the thymus located
+function
anterior and superior medistina but is replaced by CT after puberty
site of T cell maturation
two lobes
where is the spleen located
L hypochondriac region
what passes through hilum of spleen?
- autonomic nerve fibers, splenic artery, splenic vein, and efferent lymph
- on medial surface (related to L. kidney and stomach)
lateral surface of spleen
- directly contacts diaphragm
- has superior and inferior borders
- behind rib 10
- filters old and damaged RBCs (which live 120 days)
which organs can take over for the spleen if removed?
liver and red bone marrow
how many tonsils do we have?
5-pharygeal (becomes CT after childhood), palatine and lingual pairs
-partially encapsulated
function of tonsils
produce antibodies and contain B lymphocytes
where do lymphatic trunks drain?
most into thoracic duct–>junction of L internal jugular and L subclavian veins
from where does the thoracic duct originate/
cisterna chyli in front of LI and LII vertebrae
-cisterna chyli receive lymph from intestinal and lumbar trunks
where does lymph drain into
- right side head and neck/upper limb goes to r lymphatic duct
- GI, lower limbs, thorax, and L side of body goes to thoracic duct