lymph

a colourless, watery fluid that surrounds the body tissues and circulates in the LYMPHATIC SYSTEM . It is derived from blood and is similar to PLASMA , comprising 95% water with PROTEIN , sugar, salts and LYMPHOCYTES . The lymph is circulated by muscular action, and passes through LYMPH NODES , which act as filters, and is eventually returned to the BLOOD via the thoracic duct (one of the two main vessels of the lymphatic system).