Lymphatic System Organs & Functions
What is MALT?
(Mucosa-Associated Lymphatic Tissue) Protects respiratory and digestive tract
What are the two parts of the Lymphatic System?
1)Lymphatic vessels and 2)Lymphoid tissues and organs
What is lymph?
excess tissue fluid
What is the role of the thymus?
functions at peak level during childhood only; produces thymosin to program lymphocytes
How is Lymph made?
it is the interstitial fluid that is forced out at the beginning of the capillary beds and is not put back into the bloodstream.
Which leukocytes are present in lymph nodes?
lymphocytes (destroy specific invaders) and Macrophages (destroy non-specific invaders)
What does the fluid return through to get to the circulatory veins near the heart?
the right Lymphatic duct and the thoracic duct
What is the role of the tonsils?
trap and remove debris and foreign substances at pharynx
What is the role of the spleen?
Filters blood of bacteria and viruses, destroys worn out RBC's, forms blood in fetus, stores some blood
What is the job of lymph nodes?
They help protect to the body by removing foreign materials such as bacteria and tumor cells
What is the role of Lymphatic collecting vessels?
To transport Lymph from Lymph capillaries to nodes where it is filtered until it's return to the circulatory veins
What are the functions of the Lymphatic System?
To transport fluids back to blood and act as the bodies defense and resistance to disease. Returns excess interstitial fluid to Cardiovascular System Provides defense against infectious diseases and cancer Harbors leukocytes Absorbs dietary lipids from digestive tract
Lymphatic vessels Lymph nodes Spleen Tonsils (5) Thymus Appendix Peyer's patches Associated lymphoid tissues (SALT, MALT, GALT)
Transport lymph Leukocyte movement Primary organ of immunity "Filter" lymph (macrophages & phagocytosis) Monitor lymph for pathogens (lymphocytes & adaptive immunity) Destroys worn-out erythrocytes (macrophages in red pulp) Monitors blood for pathogens (Lymphocytes in white pulp) Reservoir for blood Provides immune activity around oral cavity Trap and digest bacteria and particulate matter T-Cell development Similar function to Peyer's patches Harbors beneficial bacteria for recolonizing colon Provides immune surveillance around small intestine Reduce bacterial numbers in GI tract Important for immune development Deep to skin and mucous epithelia Concentration of macrophages and lymphocytes in connective tissue Monitor for pathogen breach of skin and mucous membranes
What is the role of the Peyer's Patches?
Capture and destroy bacteria in intestines
What parts of lymph are returned in the blood?
Dissolved protein and water
List the organs involved in the Lymphatic System
Lymph Lymph nodes & vessels Spleen Thymus Tonsils SALT and MALT
What does MALT include?
Peyer's Patches, Tonsils, and other small groups of lymphatic tissue
What are harmful materials that enter Lymphatic vessels?
Proteins, cell debris, cancer cells, bacteria, and viruses
