lymphatic system defined in 1951 yearlymphatic system - lymphatic system;
lymphatic system - System of fluid-containing tubes present in vertebrates. A blindly-ending meshwork of small tubes (lymph capillaries) permeates most tissues (not nervous system), and connects up into ever larger vessels (but not usually larger than 2-3 mm. diameter) which finally join venous system usually near the heart. Lymph is drained from the tissues into the blood by this system. Because of high permeability of lymph capillaries, large molecules and particles from the intercellular spaces, including invading bacteria, which cannot get through blood capillary walls, are carried away with the lymph. In the course of the lymphatic vessels in some vertebrates are lymph nodes, which filter out and destroy bacteria in the lymph, and supply lymphocytes to it. The lymph moves by contractility of vessels; or by squeezing of lymphatic vessels by neighbouring skeletal muscles, the larger vessels having valves which ensure flow in one direction; or (except in birds and mammals) by lymph hearts.
near lymphatic system in Knolik
definition of word "lymphatic system" was readed 1018 times