Chapter 21 Flashcards
lymphatic system
transports fluid that has escaped from the blood vessels, back to the bloodstream
immune system
contains and destroys disease-causing organisms
lymphatic system
–a system of vessels that run throughout the body
vessels collect lymph from the loose CT around blood capillaries and carry it to the great veins at the root of the neck
-lymph only flows towards the heart (one-way system)
functions of the lymphatic vessels
return excess tissue fluid to the blood
return leaked proteins to the blood
carry absorbed fat from the intestine to the blood
play a part in the immune system
types of lymphatic
lymph capillaries lymphatic collecting vessels lymph nodes lymph trunks lymph ducts (direction of flow)
lymph capillaries
first receive lymph from loose CT around capillaries
lacteals: special lymph capillaries located in the microvilli of the small intestine that receive digested fats
lymphatic collecting vessels
receive lymph from the (lymph) capillaries
contain numerous valves to ensure the one-way flow of lymph
lymph nodes
bean-shaped organs scattered along the lymphatic collecting vessels
large clusters in the cervical, axillary, and inguinal regions
contain a reticular fiber network that houses a variety of macrophages
the macrophages cleanse the lymph of pathogens
5 major lymph trunks
lumbar trunks: lower limbs and pelvic organs
intestinal trunks: fatty lymph from the digestive organs
bronchomediastinal trunks: thoracic viscera and wall
subclavian trunks: upper limbs and inferior neck
jugular trunks: head and neck
lymph ducts
form from the uniting of lymph trunks
empty into the veins of the neck
individuals have one or two:
thoracic duct: present in all individuals, empties into the junction of the left internal jugular and left subclavian veins
right lymphatic duct: present in about 20% of people
