Chapter 21 - Lymphatic System Flashcards
Lymphatic System Components
Lymphatic vessels & lymph
Lymphatic vessels include
Lymph capillaries -> lymphatic collecting vessels -> lymph trunks -> lymph ducts
It is a one-way system, only TOWARD the heart
lymph
fluid from loose CT that surrounds tissue
more fluid exits from the arteriole side than leaves from the venule side
lymph capillaries
collect the excess tissue fluid
single layer of endothelium
drains into lymphatic collecting vessels
located at most places blood capillaries occur EXCEPT bone, teeth, bone marrow, and CNS
Specialized ones in small intestine called lacteals
lacteals
specialized for fat absorption
chyle
fatty lymph
lymph collecting vessels
carry fluid to nodes, which filter and purify
have same 3 tunics as blood vessels and contain valves
superficial vessels travel with veins; deep vessels travel with arteries
have many valves
Movement of lymph is propelled by
skeletal muscle action
artery pulsations
tunic media
normal movements of trunk and limbs
Lymph nodes
remove pathogens from lymph
bean-shaped, often occur in clusters
If cancer gets into lymphatic system, the cells can be widely dispersed and tumors can develop at nodes
Microscopic anatomy of the node
Surrounded by fibrous capsule (dense CT) Trabeculae extend inward Afferent and efferent lymphatic vessels Hilus Lymph sinuses are located between afferent and efferent vessels Follicles (nodules)
Hilus
indented region in lymph nodes (efferent exit through)
Macrophages
consume foreign particles
Follicles (nodules)
masses of lymphoid tissue
Lymph Trunks
Formed by convergence of largest lymphatic collecting vessels
Drain large areas of the body
What are the large areas of the body that lymph trunks drain
lumbar trunks intestinal trunk bronchomediastinal trunks subclavian trunks jugular trunks
lumbar trunks
drain lower limbs, pelvic organs, anterior abdominal wall
intestinal trunks
drains stomach, intestines, digestive organs
bronchomediastinal trunks
drain thoracic viscera/wall
Subclavian trunks
drain upper limbs, inferior neck, superior thoracic wall
Jugular trunks
drain head and neck