section_path: Physiology/Lymphatic system
section_name: Lymphatic system
paragraph_text: Lymphatic system
  
  In mammals, blood is in equilibrium with lymph, which is continuously formed in tissues from blood by capillary ultrafiltration. Lymph is collected by a system of small lymphatic vessels and directed to the thoracic duct, which drains into the left subclavian vein, where lymph rejoins the systemic blood circulation.