Cardiovascular System

1. Cardiovascular System • Blood • The Heart • Blood Vessels & Circulation

2. Blood • Introduction • Functions of Blood • Blood Composition • Plasma • Formed Elements • Hemostasis

3. The Blood • To View Video: • Move mouse cursor over slide title-link • When hand appears, click once • ASX Video plays about 20 min

4. Introduction • Circulatory System Components • Circulatory System Functions • Functions of Blood

5. Learning Objectives • Circulatory System: • Explain how the cardiovascular system is related to the circulatory system • FunctionsofBlood: • List & describe five functions of blood

6. Circulatory System • Component Systems: • Cardiovascular system • Lymphatic system • Functions of Circulatory System: • Transport • Regulation of body fluids • Defense against pathogens

7. Functions of Blood • Transport of dissolved gases, nutrients, hormones, & metabolic wastes • Regulation of pH & electrolytecomposition of interstitial fluids • Restriction of fluid losses due to damaged vessels or injury • Defense against toxins & pathogens • Temperature homeostasis

8. Composition of Blood • Plasma & Formed Element • Blood Collection & Analysis

9. Learning Objectives • BloodComposition: • Describe the important components of the blood • BloodCollection&Analysis: • Describe some of the basic physical features of blood & explain how blood is collected • Explain how blood volume can be estimated

10. Blood Tissue • Blood is a fluid connective tissue • cellularcomponents: formed elements • RBCs, WBCs, platelets • matrix: plasma • “fibrous” portion – plasma proteins • ground substance - serum

11. Blood Composition • Plasma • connective tissue matrix: • plasma proteins – in solution • serum – ground substance (H2O) • Formed elements • connective tissue cells: • erythrocytes – red blood cells (RBCs) • leukocytes – white blood cells (WBCs) • platelets – cell fragments

12. Blood Collection • Venipuncture • commonsampling technique – median cubital vein (ant. surf elbow) • superficial veins easy to locate • walls of veins are thinner • venous blood pressure is relatively low allowing puncture wound to seal quickly • most blood analyses

13. Blood Collection • Capillary puncture • finger tip is most common • blood smear technique • Arterial puncture • uncommon sampling technique • gas exchange efficiency – radial artery (wrist) or brachial artery (elbow)

14. Whole Blood: Plasma & Formed Elements

15. Plasma Analysis

16. Formed Element Analysis

17. Hematocrit

18. Physical Characteristics • temperature • 38 0C (100.4 0 F) • slightly higher than normal core B.T. • viscosity • 5X that of H20 • interaction btw/ proteins, formed elements, & H20 • pH • 7.35 – 7.45 • slightly alkaline average:7.4

19. Blood pH

20. Blood Volume • Male • 5 – 6 liters • Female • 4 – 5 liters • Relative to body size • gender differences reflect differences in ave. body size • calculation: 0.07 (7%) of body weight in kg (1kg = 2.2lb)

21. Blood Volume • Blood volume terms • hypovolemic – low blood volume • normovolemic – normal blood volume • hypervolemic – excessive (high) blood volume

22. Plasma • Plasma & Interstitial Fluid • Plasma Proteins • Serum

23. Learning Objectives • Plasma: • Discuss the composition & functions of plasma • Discuss the origin of plasma proteins

24. Plasma -v- Interstitial Fluid • Plasma • 46-63 % whole blood: ave. 55 % • 92 % H2O • 8 % dissolved proteins & ions • Interstitialfluid • 96 % H2O • similar ion conc. as plasma • smaller conc. of proteins & dissolved gasses

25. Plasma Proteins • Albumins • 60 % (most abundant) • contribute to osmotic pressure • function: - transportof fatty acids, thyroid hormones, some steroid hormones, & other subst.

26. Plasma Proteins • Globulins • 35 % • immunoglobulins – a.k.a., antibodies • function: attackforeign proteins &pathogens • transport globulins • function: bindsmall ions, hormones, etc to prevent loss at kidneys

27. Plasma Proteins • Fibrinogen • 4 % • function: - blood clotting • form fibrin strands • serum – blood fluid from which clotting factors have been removed

28. Plasma ProteinOrigins • Liver • 90 % of plasma proteins • all albumins • fibrinogen • most globulins • Lymphocytes – immunoglobulins • Endocrine organs – peptide hormones Ex: α & β cells of pancreas  insulin & glucagon

29. Serum • Watery portion of blood containing dissolved substances • electrolytes: Na+, K+, Ca2+, Mg+, Cl-, HCO3-, etc • organic nutrients: fatty acids, amino acids, glucose, etc • organic wastes: urea, ammonium ions, etc • W/out clotting factors or clotting proteins

30. Formed Elements • Origin & Production • Erythrocytes (Red Blood Cells) • structure & function • hemoglobin • erythropoiesis • blood typing • Leukocytes (White Blood Cells) • structure & function • leukopoiesis • Platelets • structure & function

31. Learning Objectives • FormedElements: • Describe the origin & formation of formed elements in blood • RBCs: • List the characteristics & functions of red blood cells • Describe the structure of hemoglobin, and indicate its functions

32. Learning Objectives • RBCs: (cont.) • Describe the recycling system for aged or damaged RBCs • Define erythropoiesis, identify the stages involved in erythrocyte maturation, & describe the homeostatic regulation of RBC production

33. Learning Objectives • RBCs: (cont.) • List examples of important tests & cite the normal values for each test • Explain the importance of blood typing on the basis of ABO & Rh incompatibilities

34. Hemopoiesis • Production of blood • Stem cells • produce daughter cells that remain capable of division throughout life • Hemocytoblasts • divide to produce: • lymphoid stem cells lymphocyte production • myeloid stem cells production of allother: RBCs, platelets, & WBCs

35. Erythrocytes:Red Blood Cells • RBCs = 99% of formed elements • Contain hemoglobin • protein • binds O2 & CO2 • Imparts deep red color to blood when bound to oxygen: oxyhemoglobin

36. RBC Trivia • # RBCs/μl (mm3): • = 4.5-6.0 million for male • = 4.2-5.5 million for female • # RBCs in 1 drop of blood = 260 million • total # RBCs in ave adult = 25 trillion • RBCs account for 1/3 of the total # of cells in the human body

37. Red Blood Cells • Hematocrit • % of whole blood occupied by cellular components • Adult male – 46% (40-54%) • Adult female – 42% (37-47%) Androgens (♂ hormones) stimulate RBC production; estrogens (♀ hormones) do not

38. Blood Smear RBC WBC platelet

39. RBC Structure & Function • Structure • biconcave disk • no nucleus in mature, circulating RBCs • hemoglobin (Hb) – packs RBC • Effect on function • large surface area – rapid absorption & release of O2 • formation of stacks – rouleaux • allows easy passage through vessels • flexibility – ability to squeeze through capillaries

40. Hemoglobin Structure • Structure • Quaternary shape – 4 globular polypeptide chains • 2 alpha (α) chains • 2 beta (β) chains • Each subunit has 1 hemegroup containing Fe • Sickle-cell anemia • a.a. sequence error in structure of β chain • RBCs “sickle” in low O2 conditions

41. Pleiotropy Normal RBCs

42. Hemoglobin Function • Oxygentransport • 280 million Hb molecules/RBC • each Hb has 4 heme groups • Fe in each heme carries 1 O2 • a single RBC carries > 1 billion O2 molecules • 98.5% O2 in blood carried by Hb • Oxyhemoglobin • HbO2 • in↑oxygen environ, Hb binds O2 • in↓oxygen environ, Hb releases O2

43. Hemoglobin Function • Carbon dioxide transport • CO2 binds to α & β chains • 23% CO2 in blood carried by Hb - remainder carried as HCO3- or dissolved gas • Carbaminohemoglobin • HbCO2 • in↑carbon dioxide environ, Hb binds CO2 • in↓carbon dioxideenviron, Hb releases CO2

44. RBC Life Span & Circulation • route from heart, to peripheral tissues, back to heart takes 1 min – extremely stressful collisions • travels 700 miles in120 days • worn cells are phagocytized by WBCs • 1% replaced @ day • 3 million new RBCs enter circulation @ sec

45. Erythropoiesis Stimulation of erythropoiesis due to hormone erythropoietin (EPO) produced by kidney in response to hypoxia (↓O2)

46. Blood Typing • Based on surface features of RBCs • antigens – surface features (agglutinogens) that trigger immune responses • RBCs have 50 different kinds of surface antigens • 3 are especially important:A, B, & Rh • Affected by antibodies • agglutinins – antibodies that attack RBCs w/ non-self antigens

47. Blood Types • TypeA (40% US population) • antigen A present on RBC • plasma carries anti-B antibodies • TypeB(10% US population) • antigen B present on RBC • plasma carriesanti-A antibodies • TypeAB(4% US population) • antigens A & B present on RBC • plasma carries no ant-A or anti-B antibodies

48. Blood Types • TypeO(46% US population) • no A or B antigens present on RBC • plasma carries both anti-A & anti-B antibodies

49. Blood Groups universal recipient universal donor

50. Blood Types • Rh factor • antigen present – positive Rh factor = Rh+ • antigen absent – negative Rh factor = Rh- • no anti-Rh antibodies are present in Rh- individuals unless due to previous exposure to Rh+ blood • “Rh” omitted in blood type terminology Ex: O+ or A-