Herlihy The human body in health and illness ch

Herlihy The human body in health and illness ch 20 What is lymph? - A clear pale yellow fluid that resembles plasma . What is lymph composed of? - Water, electrolytes, waste from metabolizing cells, and proteins What do lymphatic vessels do? - Pick up tissue fluid and to transport it toward the heart What is the function of the lymphatic system? - Pick up tissue fluids and transport them to heart What are the 3 main functions of the lymphatic system? - • Return interstitial fluid to the blood • Absorbs fats and fat soluble vitamins • Helps the body defend itself against infections How does lymph flow? - Flows from the lymphatic capillaries towards the heart through a series of larger and larger lymphatic vessels until it reaches the two largest lymphatic ducts What are the four ways that lymph move? - Milking, movement of chest during respiration, rhythmic contraction of smooth muscle in lymph vessels, presence of valves How does movement of chest move lymph? - Contraction and relaxation of chest muscles changes intrathoracic pressure, pressure increase flow of lymph toward subclavian vein How do valves help lymph move ? - Valves prevent backflow of lymph. if lymph moves at all it will move toward the heart Where does the right lymphatic duct drain lymph? - Right subclavian vein Where does the thoracic duct drains lymph? - Left subclavian vein What is the difference between lymphatic organs and lymphatic nodules ? - Lymphatic organs are encapsulated masses of lymph tissue while lymphatic nodules are partially or non-encapsulated What are the lymphatic organs ? - lymph nodes, thymus gland, spleen What are the three larger clusters of lymph nodes called? - • cervical lymph nodes • axillary lymph nodes • inguinal lymph nodes What is the function of cervical lymph nodes? - Drain and cleanse lymph coming from head and neck. (Enlarged tinder cervical lymph nodes often accompany upper respiratory infections ) What is the function of axillary lymph nodes? - Drain and cleanse lymph coming from upper extremities, shoulders, and breast area (cancer cells that leave breast are often found in axillary lymph nodes) What is the function of inguinal lymph nodes ? - Drain and cleanse lymph from lower extremities and external genitalia What are lymph nodules made of ? - Lymphocytes and macrophages What are compartments of the lymph node called? - Lymph nodules In adults, how does the thymus gland chamge? - It shrinks as we age, and is replaced with adipose and connective tissue but still retains age related role in immune function What hormone does the thymus gland secrete? - thymosin What is the function of thymosins? - Promote maturation of T cells What is the largest lymphatic organ in the body? - spleen Where is the spleen located? - LUQ What is the function of the spleen ? - filters blood What 2 types of tissue does the spleen have? - White pulp and red pulp What does white pulp contain ? - lymphocytes and macrophages What does read pulp contain ? - Venous sinuses filled with blood, lymphocytes and macrophages Through which artery does blood enter the spleen? - Splenic artery What happens to microbes go that are cleansed from the blood in the spleen ? - Destroyed by leukocytes Why is the spleen nicknamed the graveyard of red blood cells? - because it destroys in phagocytizes old worn out RBCs and stores up to 30% of platelets