Internal Transport

1. Internal Transport Chapter 43

2. KEY CONCEPTS • A circulatory system typically consists of blood, a heart, and a system of blood vessels or spaces through which blood circulates

3. Learning Objective 1 • Compare and contrast internal transport in animals with no circulatory system, those with an open circulatory system, and those with a closed circulatory system

4. Internal Transport • Diffusion • in small, simple invertebrates (sponges, cnidarians, flatworms) • Specialized circulatory systems • in larger animals • blood, heart, blood vessels or spaces

5. No Circulatory System

6. Fig. 43-1a, p. 920

7. Gastrovascular cavity Pharynx Mouth (b) Fig. 43-1b, p. 920

8. Interstitial Fluid • Tissue fluid between cells • in all animals • Brings oxygen, nutrients in contact with cells

9. Open Circulatory System • Found in arthropods, most mollusks • Blood flows into a hemocoel • bathing tissues directly

10. Open Circulatory Systems

11. Stomach Ventricle Atrium Gills Fig. 43-2a, p. 921

12. Artery Ostia Tubular heart Fig. 43-2b, p. 921

13. Closed Circulatory System • Found in all vertebrates • and some invertebrates • Blood flows through a continuous circuit of blood vessels

14. Closed Circulatory System

15. Dorsal vessel Contractile blood vessels Ventral vessel Lateral vessels Fig. 43-3, p. 921

16. KEY CONCEPTS • Arthropods and most mollusks have an open circulatory system in which blood bathes the tissues directly • Some invertebrates and all vertebrates have a closed circulatory system in which blood flows through a continuous circuit of blood vessels

17. Vertebrate Circulatory System 1 • Muscular heart • pumps blood into arteries, capillaries, veins • Transports • nutrients, oxygen, wastes, hormones

18. Vertebrate Circulatory System 2 • Helps maintain • fluid balance, pH, body temperature • Defends body against disease

19. Learn more about open and closed circulatory systems by clicking on the figures in ThomsonNOW.

20. KEY CONCEPTS • The vertebrate circulatory system transports nutrients, oxygen, wastes, and hormones; helps maintain fluid balance, appropriate pH, and body temperature; and defends the body against disease

21. Learning Objective 2 • Compare the structure and function of plasma, red blood cells, white blood cells, and platelets

22. Plasma • Water and salts • Substances in transport • Plasma proteins • albumins • globulins • fibrinogen

23. Red Blood Cells(Erythrocytes) • Transport oxygen and carbon dioxide • Produce hemoglobin • red pigment that binds with oxygen

24. White Blood Cells (Leukocytes) • Defend body against disease organisms • Lymphocytes and monocytes • agranular white blood cells • Neutrophils, eosinophils, basophils • granular white blood cells

25. Platelets • Patch damaged blood vessels • Release substances essential for blood clotting

26. Vertebrate Blood

27. Whole blood Plasma Cell components Plasma proteins White blood cells (leukocytes) Lipo- proteins Albumins Globulins Fibrinogen Water Salts Dissolved gases Hormones Glucose Wastes 1 to 2 µm 7 µm Clotting proteins Red blood cells (erythrocytes) Platelets Agranular leukocytes Granular leukocytes Fig. 43-4a, p. 923

28. Learn more about the composition of vertebrate blood by clicking on the figures in ThomsonNOW.

29. Learning Objective 3 • What is the sequence of events involved in blood clotting?

30. Blood Clotting • Damaged cells and platelets • release substances that activate clotting factors • Prothrombin is converted to thrombin • converts fibrinogen to insoluble protein (fibrin) • Fibrin forms long threads • make up webbing of clot

31. Blood Clotting

32. 1 Injury to blood vessel 2 Wall of vessel contracts 3 Platelets adhere to collagen fibers of damaged vessel wall 4 More permanent clot forms Platelet plug Blood flow decreases Blood flow decreases Blood flow Blood flow ceases Fig. 43-5a, p. 924

33. 3. Platelets adhere to collagen fibers of damaged vessel wall 4. More permanent clot forms 1. Injury to blood vessel 2. Wall of vessel contracts Blood flow decreases Blood flow decreases Blood flow Blood flow ceases Platelet plug Stepped Art Fig. 43-5a, p. 924

34. Prothrombin Damaged cells and platelets release substances that activate clotting factors Prothrombin activator Ca2+ Fibrinogen Thrombin Ca2+ Fibrin threads (clot) Fig. 43-5b, p. 924

35. Learning Objective 4 • Compare the structure and function of different types of blood vessels, including arteries, arterioles, capillaries, and veins

36. Blood Vessels 1 • Arteries • carry blood away from the heart • Veins • return blood to the heart

37. Blood Vessels 2 • Arterioles • constrict (vasoconstriction) • dilate (vasodilation) • Arterioles regulate blood pressure and distribution of blood to tissues

38. Blood Vessels 3 • Capillaries • thin-walled exchange vessels • allow materials to transfer between blood and tissues

39. Blood and Lymphatic Vessels

40. Vein Lymphatic Artery Venule Arteriole Capillary bed Lymph node Capillaries (a) Lymph capillaries Movement of interstitial fluid Fig. 43-6a, p. 926

41. Outer coat (connective tissue) VEIN Endothelium Smooth muscle ARTERY Outer coat (connective tissue) Endothelium CAPILLARY (b) Fig. 43-6b, p. 926

42. Fig. 43-6c, p. 926

43. A Capillary Network

44. Precapillary sphincter Metarteriole True capillaries Venule Arteriole (a) Sphincters closed Fig. 43-7a, p. 927

45. Precapillary sphincter Metarteriole True capillaries Arteriole Venule (b) Sphincters open Fig. 43-7b, p. 927

46. Learning Objective 5 • Trace the evolution of the vertebrate cardiovascular system from fish to mammal

47. The Vertebrate Heart • One or two atria • receive blood • One or two ventricles • pump blood into arteries

48. The Vertebrate Heart

49. The Fish Heart • One atrium and ventricle • single circuit of blood flow

50. Atrium Sinus venosus Veins from the body Valve Ventricle Aorta Valve (a) Fishes Fig. 43-8a, p. 928