1. THE CIRCULATORY SYSTEMS: The Cardiovascular and Lymphatic Systems

2. Overview of the Circulatory System Cardiovascular System Lymphatic System The Medium The Conduit The Pump The Pathway

3. Cardiovascular System: The Medium Cardiovascular System Lymphatic System The MediumBlood The Conduit The Pump The Pathway

4. Blood: The “river of life” The only fluid tissue of the body

5. Blood Composition

6. 45% blood cells –Erythrocytes (RBC), which transport oxygen –Leukocytes (WBC), which protect the body against pathogens –Platelets, cell fragments that aid in blood clotting

7. Blood Composition 55% plasma –Straw-colored liquid that consists of 90% water and dissolved substances (nutrients, salts, oxygen, carbon dioxide, hormones, plasma proteins, and wastes)

9. Is Blood Blue?

10. The color of blood depends on the amount of oxygen it is carrying –Bright red (oxygen-rich blood) –Dark red (oxygen-poor blood)

11. Cardiovascular System: The Conduit Cardiovascular System Lymphatic System The MediumBlood The ConduitArteries and Veins The Pump The Pathway

12. The Conduit Arteries, arterioles, and capillary beds carry O 2 rich blood away from the heart Venules and veins carry O 2 poor blood to the heart

14. Exceptions Pulmonary (lung) veins carry O 2 rich blood from the lungs to the heart. Pulmonary arteries carry O 2 poor blood from the heart to the lungs.

15. Arteries vs. Veins

16. The Similarities Both carry blood Both have three tunics (3-layered) –Tunica interna (inner layer) –Tunica media (middle layer of smooth muscle) –Tunica externa (outer layer)

18. The Differences: Arteries Arteries have thicker walls in order to withstand the higher pressure due to increased blood flow from the heart

19. The Differences: Arteries Most arteries carry O 2 rich blood from the heart Capillary beds are one cell layer thick and provide nourishment to cells and carry waste away from cells

20. The Differences: Veins Veins have thinner walls Veins have larger openings (lumen) Large veins have valves to prevent the backflow of blood

22. The Differences: Veins Action of lungs and muscles aid in venous return Most veins carry O 2 poor blood back to the heart

23. Cardiovascular System: The Pump Cardiovascular System Lymphatic System The MediumBlood The ConduitArteries and Veins The PumpThe Heart The Pathway

24. The Heart Located in the bony thorax (rib cage) Flanked by lungs on both sides

25. Muscular pump with four chambers –Two atrium –Two ventricles

26. Circulation of Blood Through the Heart

27. Cardiovascular System: The Pathway Cardiovascular System Lymphatic System The MediumBlood The ConduitArteries and Veins The PumpThe Heart The PathwaySystemic and Pulmonary Circulation

29. The Lymphatic System Cardiovascular System Lymphatic System The MediumBlood The ConduitArteries and Veins The PumpThe Heart The PathwaySystemic and Pulmonary Circulation

30. The Lymphatic System: The Medium Cardiovascular System Lymphatic System The MediumBloodLymph The ConduitArteries and Veins The PumpThe Heart The PathwaySystemic and Pulmonary Circulation

31. Lymph Means “clear water” Consists of fluids leaked from blood vessels that remain in tissue spaces Primarily water with a small amount of dissolved proteins

32. Lymphatic System: The Conduit Cardiovascular System Lymphatic System The MediumBloodLymph The ConduitArteries and Veins Lymphatic vessels The PumpThe Heart The PathwaySystemic and Pulmonary Circulation

33. Lymphatic Vessels Pick up excess tissue fluid and return it to the bloodstream One-way system (lymph only flows toward the heart) Vessels become successively larger until it is returned to the venous system

34. Like veins, lymphatic vessels –Have thin walls –Are large vessels with valves –Have lower pressure than arteries –Move lymph along by the action of lungs and muscles

35. Lymphatic Capillaries

36. Lymphatic capillaries drain tissues of fluid then deposit the fluid into lymphatic vessels. Tissue fluid flows into the lymphatic vessel when the fluid pressure increases in tissues.

37. Inflow from Tissue Fluid Endothelial cells overlap to allow fluid in, not out.

38. Lymphatic System: The Pump Cardiovascular System Lymphatic System The MediumBloodLymph The ConduitArteries and Veins Lymphatic Vessels The PumpThe HeartNo Pump The PathwaySystemic and Pulmonary Circulation

39. No pump System The lymphatic system has no pump. Lymph moves along by the action of lungs and muscles

40. Lymphatic System: The Pathway Cardiovascular System Lymphatic System The MediumBloodLymph The ConduitArteries and VeinsLymphatic Vessels The PumpThe HeartNo Pump The PathwaySystemic and Pulmonary Circulation Right Lymphatic Duct and Thoracic Duct

41. Lymphatic System: The Pathway The lymphatic vessels on the right side of the body drains into the right lymphatic duct then into the right subclavian vein

43. The rest of the lymphatic vessels drain into the thoracic duct then into the left subclavian vein

45. Lymphatic Nodes Lymph nodes protect the body by removing foreign materials, such as bacteria and tumor cells Produce lymphocytes that function in the pathogen-fighting response Vary in shape and size

47. Lymphatic Organs Lymphatic organs protect the body against pathogens –Spleen (filters and cleanses the blood of bacteria, viruses, and other debris) –Thymus –Tonsils –Peyer’s patches