1. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Memmler’s The Human Body in Health and Disease 11 th edition Chapter 16 The Lymphatic System and Lymphoid Tissue

2. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Lymphatic System System of tissues and vessels Scattered throughout the body Services almost all regions

3. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Functions of the Lymphatic System Fluid balance –Lymph fluid Protection from infection Absorption of fats

4. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The lymphatic system in relation to the cardiovascular system. Lymphatic vessels pick up fluid in the tissues and return it to the blood in vessels near the heart. Zooming In: What type of blood vessel receives lymph collected from the body?

5. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-1: What are the three functions of the lymphatic system?

6. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphatic Circulation One-way system Begins in tissues Ends in bloodstream

7. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphatic Capillaries Capillary walls (endothelium) are flattened epithelial cells More permeable than blood capillaries Overlapping cells form one-way valves Arise blindly (closed at one end) Lacteals absorb digested fats

8. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-2: What are two differences between blood capillaries and lymphatic capillaries?

9. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphatic Vessels Superficial sets Deep sets Nodes Right lymphatic duct Thoracic duct (left lymphatic duct) –Cisterna chyli

10. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Vessels and nodes of the lymphatic system. (A) Lymph nodes and vessels of the head. (B) Drainage of right lymphatic duct and thoracic duct into subclavian veins.

11. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-3: What are the two main lymphatic vessels?

12. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question: What is the name for the lymphatic vessels that absorb digested fats? a. lacteals b. cisterna chyli c. inguinal nodes

13. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer: a. lacteals

14. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Movement of Lymph Segments of vessels located between the valves contract rhythmically Skeletal muscles compress vessels

15. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphoid Tissue Distributed throughout the body Makes up specialized organs of lymphatic system

16. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymph Nodes Structure –Fibrous connective tissue capsule –Afferent lymphatic vessel –Hilum –Sinuses –Cords –Nodules –Medulla –Efferent lymphatic vessel Grouping –Cervical nodes –Axillary nodes –Mesenteric nodes –Inguinal nodes

17. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Structure of a lymph node. (A) Arrows indicate the flow of lymph through the node. (B) Section of a lymph node as seen under the microscope (low power). (B, Reprinted with permission from Cormack DH. Essential Histology. 2nd ed. Philadelphia: Lippincott Williams & Wilkins, 2001.) Zooming In: What type of lymphatic vessel carries lymph into a node? What type of lymphatic vessel carries lymph out of a node?

18. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-4: What is the function of the lymph nodes?

19. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question: True or False?: The popliteal lymph nodes in the right leg drain into the right lymphatic duct.

20. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer: False: The popliteal nodes drain into the thoracic duct, because the thoracic duct receives lymph from all parts of the body except those in the superior right quadrant of the body.

21. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Spleen Cleanses blood –Filtration –Phagocytosis Destroys old red blood cells Produces red blood cells before birth Is reservoir for blood

22. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-5: What is filtered by the spleen?

23. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Thymus Plays key role in early immune system development Produces thymosin –Develops T lymphocyte cells –Promotes lymphocyte growth –Promotes lymphoid tissue activity Shrinks after puberty

24. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-6: What kind of immune system cells develop in the thymus?

25. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Tonsils Remove contaminants and trap pathogens Palatine tonsils Pharyngeal tonsil (adenoids) Lingual tonsils Surgery to treat if recurrent infection or enlarged tonsils make swallowing/breathing difficult

26. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-7: Tonsils filter tissue fluid. What is the general location of the tonsils?

27. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Other Lymphoid Tissue Appendix Mucosal-associated lymphoid tissue (MALT) –Peyer patches Gut-associated lymphoid tissue (GALT)

28. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins The Reticuloendothelial System Cells responsible for destroying worn-out blood cells, bacteria, cancer cells and other harmful foreign substances Monocytes Macrophages –Kupffer cells –Dust cells

29. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Disorders of the Lymphatic System and Lymphoid Tissue Lymphangitis Septicemia Lymphadenitis –Cervical –Chronic

30. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphedema Tissue swelling due to obstruction of lymph flow caused by Infection of lymphatic vessels Vessel blockage –Malignant growth –Parasites Loss of lymphatic vessels from injury or surgery

31. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphadenopathy Enlarged lymph nodes accompany certain diseases and infections Acquired immunodeficiency syndrome (AIDS) Infectious mononucleosis

32. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Splenomegaly Enlarged spleen accompanies certain diseases and infections Scarlet fever Typhus fever Typhoid fever Syphilis Tropical parasitic diseases Splenic anemia

33. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Question: What is the name of the collection of cells that are responsible for destroying worn-out cells, cellular debris, bacteria, and other harmful substances? a. the MALT system b. Peyer patches c. the reticuloendothelial system

34. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Answer: c. the reticuloendothelial system

35. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Lymphoma Any tumor in lymphoid tissue Malignant disease –Hodgkin disease –Non-Hodgkin lymphoma

36. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins Checkpoint 16-8: What is lymphadenopathy? Checkpoint 16-9: What is lymphoma and what are two examples of malignant lymphoma?

37. Copyright © 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins End of Presentation