Lymphoid Organ Anatomy Flashcards
lymph nodes anatomy
- 100s throughout body, grouped together (especially in groin + axilla region)
- found at junctions of lymphatic vessels
- encapsulated in fibrous connective tissue w/vessels coming in and out
incoming vessels
- afferent vessels
- majority of lymphatic vessels within lymph nodes
- create network of sinuses containing cells
outgoing vessels
- efferent vessels
- take lymph back out of node
nodules
- divide up interior of lymph nodes
- open spaces containing lymphocytes and macrophages
sinuses
- 3 sinuses in lymph nodes: cortical, subcapsular, medullary
- as lymph passes through them, rid lymph of infectious organisms and other debris
spleen
- located in upper left abdomen
- covered in thin, fragile fibrous connective tissue
- divided into lobules
blood pathway through spleen
blood enters via splenic artery –> filtered in spleen –> leaves via splenic vein –> hepatic portal vein –> liver
thymus gland
- located on anterior surface of heart
- secretes thymosin and thymopoietin hormones
thymosin
- hormone secreted by thymus gland
- enables T cells (T-lymphocytes) to mature and function as part of immune system (attack infected/cancerous body cells)
thymopoietin
- hormone secreted by thymus gland
- enables T cells (T-lymphocytes) to mature and function as part of immune system (attack infected/cancerous body cells)
tonsils
- aka palatine tonsils
- group of lymphoid organs @ lateral posterior throat
- gather and destroy bacteria inhaled in air or food
crypts
- channels invigating tonsils
- trap bacteria and foreign matter for tonsil tissue to destory
spleen functions (2)
- extracts old/defective blood cells and platelets
- removes debris/foreign matter/bacteria/viruses/toxins from blood
lobules
divisions in spleen containing macrophages + lymphocytes
thymus gland changes over lifetime
- prominent in newborns
- grows + most active throughout childhood
- stops growing during adolescence
- eventually withers to mass of fibrous fatty tissue by old age
