Lymphatic System

• Pathway of the LS

  1. Interstitial fluid

  2. Lymphatic capillaries

  3. Lymphatic vessels

  4. Lymph nodes

  5. Lymphatic duct

  6. R and T ducts
• Functions of the LS

  • Fluid balance - return fluid to circulation
  • Lymphocyte production - WBC
  • Filtration
  • Immunity
• Fluid in the Body

  • Plasma - liquid part of the blood
  • Interstitial fluid (between tissues) - fluid in tissue space
  • Lymph - fluid in lymphatic system
• Lymph vessels


  • Transport excess tissue fluid back to the circulatory system
  • Parallel veins
  • Flows in only one direction and valves prevent backflow
  • Drains larger lymphatic vessels
• Lymph nodes


  • Tiny oval shaped structures located throughout the body including the neck and axillary area
  • Produce lymphocytes
  • Filter out harmful bacteria
  • Become inflamed if can't destroy the trapped virus, bacteria or other illness
• Thoracic duct


  • Largest and drains lymph from left upper body and all of lower body
• Right lymphatic duct


  • Drains lymph from right upper body
• Other Structures

  • Tonsils - masses of lymphatic tissue that produce lymphocytes and filter bacteria
  • Palatine - located in back of throat
  • Lingual - located at base of tongue
  • Pharyngeal - aka adenoids, located midline of nasopharynx
  • Spleen
  • Thymus gland (aka shrinking or disappearing gland)
  • Lacteal - Specialized lymphatic vessel that absorbs dietary fats
• Spleen


  • Sac-like mass of lymphatic tissue
  • Located in the left abdominal cavity below the diaphragm
  • Produces lymphocytes and monocytes
  • Filters blood, stores large amounts of RBC, and destroys fragile RBC
  • Contains white pulp and red pulp
• Thymus gland


  • Produces lymphocytes and differentiates T-cells
  • Located upper anterior chest above heart in mediastinal cavity
  • Lymphatic and endocrine gland
  • Most active during when baby
• Anaphylactic shock


  Life-threatening allergic reaction
• HIV/AIDS


  Chronic immune system disease caused by the human immunodeficiency virus
• Hodgkin's Disease


  Cancer in the lymphatic system
• Infectious mononucleosis


  Aka mono, infection caused by transmitted saliva
• Lymphedema


  Abnormal swelling caused by blockage in lymphatic system
• Tonsillitis


  Swelling of tonsils
• Lupus erythematosus


  Immune system attacks healthy tissues and organs