Functions of the Lymphatic System

• returns ? , ? , ? , ? , and ? to the blood
• involved with the absorption of fats from the digestive tract
• protects against invasion by foreign substances

Organization of the Lymphatic System

• the lymphatic system is composed of lymphatic vessels and lymphatic organs

• Lymphatic Vessels :

  • major types of lymphatic vessels include : lymphatic capillaries , collecting vessels , lymphatic trunks , and lymphatic ducts
  • Lymphatic Capillaries :
    • "blind-ended" lymphatic vessels located in the microscopic spaces between tissue cells
    • lymphatic capillaries collect excess ? and return it to the blood stream
      • interstitial fluid is the ? in the microscopic spaces between tissue cells
      • lymphatic capillaries are ? ( take up cell debris , pathogens , and cancer cells )
      • once interstitial fluid enters the lymphatic capillaries it is called ?
        • interstitial fluid and lymph are essentially the same ( major difference is ? )
    • lymphatic capillaries are located in almost all tissues of the body ( exceptions include in the CNS , cartilage , epidermis , and cornea )
    • lymphatic capillaries located in the ? of the small intestine are called ?
      • transport digested ? from the small intestine into blood
    • lymphatic capillaries merge to form larger vessels called ?
  • Collecting Vessels :
    • carry lymph into and out of structures called ?
    • the largest collecting vessels exiting the lymph nodes merge to form ?
      • examples : subclavian , lumbar , intestinal , bronchomediastinal , and jugular trunks
    • in the thoracic region , the lymphatic trunks merge to form the ?
      • largest lymphatic vessels
  • Lymphatic Ducts :
    • include the thoracic duct and right lymphatic duct
    • Thoracic Duct :
      • only on left side
      • ?
      • main collecting duct of the lymphatic system
      • receives lymph from :
        • the left side of the head , neck , and chest
        • the left upper extremity
        • the entire body below the ribs
      • typically empties lymph into venous blood at the junction of the left internal jugular vein and left subclavian vein
        • left internal jugular vein + left subclavian vein = left venous angle
    • Right Lymphatic Duct :
      • receives lymph from the ?
      • typically empties lymph into venous blood at the junction of the right internal jugular vein and right subclavian vein
        • right internal jugular vein + right subclavian vein = right venous angle

Lymph Transport

• lymph flows as a result of :
  • the "milking" action of skeletal muscle contractions
  • respiratory movements ( due to pressure changes )
  • ? that prevent backflow of lymph

Lymphatic Organs

• lymphatic organs contain ?
  • lymphatic tissue consists primarily of ? and ?

• major lymphatic organs include : the tonsils , lymph nodes , spleen , thymus gland , and appendix

• Tonsils :

  • provide protection against bacteria and other foreign substances that can enter the pharynx from the nasal or oral cavities
  • include the ? ( adenoid ) , ? , and ? tonsils

• Lymph Nodes :

  • structures located along collecting vessels that ? to remove damaged cells and microorganisms
  • remember ... lymph nodes are composed of lymphatic tissue ... therefore , they contain ? and ?
  • major lymph nodes include the cervical , axillary , thoracic , intestinal , and inguinal nodes
    • knowledge of the location of the lymph nodes and the direction of lymph flow is important in the diagnosis and prognosis of the spread ( metastasis ) of cancer
      • many cancer cells are spread by way of the lymphatic system , producing clusters of tumor cells where they lodge

• Spleen :

  • largest lymphatic organ
  • located in the ? between the stomach and the diaphragm
  • functions of the spleen include :
    • involved with immune responses
    • ?
    • RBC production in the fetus

• Thymus Gland :

  • located between the ? and the ?
  • site of ?
  • the thymus is replaced by ? throughout life
  • B-Cell maturation occurs in bone marrow

• Appendix :

  • hangs off of the cecum of the large intestine
  • has lymphatic tissue in the walls
    • therefore , has lymphocytes and macrophages