the lymph system and lymphoid organs and tissues
TRANSCRIPT
Overview
• lymphatic vessels
• lymph
• lyphoid cells and tissues
• lymphoid organso lymph nodeso spleeno thymuso tonsilso other lymphoid tissue
lymphatic vessels
• collects excess interstitial fluid
• returns fluid to blood
• one way systemo flows toward the heart
lacteals
- specialized lymph capillaries in lining of small intestine
- absorb fats
- chyle = fatty lymph that is milky white
- moves into lymph vessels
lymphatic vessels
lymphatic collecting vessels
- similar structure to veins
- more valves
- reconnect (anastamose) more often
lymphatic vessels
lymphatic ducts
- right
- thoracic
- cisterna chyli - enlarged sac where lumbar trunks meet
lymphatic vessels
• lyphangitiso when lymph vessel is
inflamed, blood vessels that feed them become congested with blood
lymphatic vessels
lymph transport
• no pump
• skeletal muscles
• muscles used to breatheo diaphragmo intercostal muscles
• smooth muscle in lymphatic trunks and thoracic duct
• valves prevent backflow
• arterial pumping
lymphoid tissue
• houses and provides a site for proliferation of lymphocytes
• surveillance point for lymphocytes and macrophages
lymphoid tissue
types
• diffuseo found in every
body organo scattered
• lymphoid follicleso solid spherical
bodieso germinal
center
clusters
- inguinal
- axillary
- cervical
functions
- filter lymph
- help activate the immune system
lymph nodes
spleen
• size of fist
• largest lymphoid organ
• site of lymphocyte proliferation
• site of immune surveillance
spleen
• cleans the bloodo stores and releases
breakdown products of RBCs
o stores blood plateletso site of RBC production
in fetus
thymus
• many thymic lobules
• cortex o rapidly dividing
lymphocytes
• medullao thymic corpuscles
development of regulatory T cells• prevent autoimmune
diseases
other lymphoid tissue
Peyer's patches
- aggregated follicles in the far end of the ileum and appendix
- immune function of GI tract