Springfield Technical Community College states that the function of the lymphatic vessels is to carry excess fluids from the body's tissues to the blood vessels and heart. Along the way this fluid, known as lymph, is filtered and cleansed of pathogens in the lymph nodes.
According to Springfield Technical Community College, the lymphatic vessels, like the veins, do not benefit from any pumping organ, and their contents are not under pressure. They rely on body movement to push the lymph along, using valves to prevent backward flow. The lymph is first released from tissues into tiny lymphatic capillaries. These capillaries join together to form larger lymphatic vessels.
Springfield Technical Community College states that the lymphatic vessels join to form yet larger vessels known as lymphatic trunks. All these different vessels eventually converge on two locations, the collecting ducts. These two ducts are the thoracic duct and the right lymphatic duct. The thoracic duct is the larger of the two; it drains the lymph from the legs, the abdomen, the left arm, the left thorax and the left side of the head into the left subclavian vein. The right lymphatic duct drains the lymph from the rest of the body into the right subclavian vein.