2. CHAPTER 27 The Blood

3. 27-2 Learning Outcomes (cont.) 27.1 Describe the components of blood, giving the function of each component listed. 27.2 Explain how bleeding is controlled. 27.3 Explain the differences among blood types A, B, AB, and O; including in the discussion which blood types are compatible.

4. 27-3 Learning Outcomes (cont.) 27.4 Explain the difference between Rh- positive blood and Rh-negative blood. 27.5Describe the causes, signs and symptoms, and treatments of various diseases and disorders of the blood.

5. 27-4 Introduction Blood –4-6 liters per adult ~ 8% of body weight –Essential functions Carries oxygen and nutrients Removes carbon dioxide and wastes Transport mechanism for hormones Regulation of body temperature

6. 27-5 Components of Blood Red blood cells – erythrocytes –Small biconcave- shaped cells –Small enough to pass through capillaries

7. 27-6 Blood Components (cont.) Hematocrit –The percentage of red blood cells –Normally about 45% White cells and platelets = 1% Plasma = 55%

8. 27-7 Blood Components (cont.) Hemoglobin –Oxyhemoglobin carries oxygen –Deoxyhemoglobin ~ carries carbon dioxide RBC count –Normally between 4 million and 6.5 million RBC/ml –Anemia

9. 27-8 Blood Components (cont.) RBCs –Produced in the red bone marrow –Life span ~ 120 days –Erythropoietin Produced by kidneys Stimulates bone marrow Released when oxygen concentrations are low

10. 27-9 Blood Components (cont.) RBC production –Iron –Vitamin B 12 –Folic acid Aging RBCs –Destroyed by macrophages in liver and spleen –Biliverdin released and converted to bilirubin by the liver

11. 27-10 White Blood Cells Leukocytes - WBCs –Granulocytes Neutrophils – 55% Eosinophils – 3% Basophils – < 1%

12. 27-11 White Blood Cells –Agranulocytes Monocytes [8%] – destroy bacteria, viruses, and toxins in blood Lymphocytes [33%] – provide immunity for the body

13. 27-12 White Blood Cells (cont.) WBC count –normally 5000 to 10,000 WBCs per cubic millimeter –Leukocytosis – high –Leukopenia – low Diapedesis

14. 27-13 Blood Platelets Also called thrombocytes Fragments of cells Needed for the clotting process Normal count – 130,000 to 360,000 platelets per cubic millimeter of blood

15. 27-14 Blood Plasma Water Proteins –Albumins ~ help to maintain blood pressure –Globulins ~ transport lipids and fat-soluble vitamins –Fibrinogen ~ needed for blood clotting Serum

16. 27-15 Blood Plasma (cont.) Nutrients –Amino acids –Glucose –Nucleotides –Lipids Gases –Oxygen –Carbon dioxide –Nitrogen

17. 27-16 Blood Plasma (cont.) Electrolytes Non-protein nitrogenous substances Waste products

18. 27-17 Apply Your Knowledge True or False: __ Hematocrit is the percentage of WBCs in the blood. __ Neutrophils destroy bacteria, viruses, and toxins in the bloodstream. __ Platelets are important to the clotting process. __ Albumin is a small plasma protein that pushes water out of the bloodstream. RBCs are biconcave-shaped cells and have hemoglobin rather than a nucleus. pulls water into RBCs T T F F ANSWER: T

19. 27-18 Bleeding Control Hemostasis – the control of bleeding Three processes of hemostasis –Blood vessel spasm –Platelet plug formation –Blood coagulation

20. 27-19 Bleeding Control (cont.)

21. 27-20 Bleeding Control (cont.) Coagulation –Fibrinogen converts to fibrin –Fibrin sticks to damaged area –Fibrin meshwork traps blood cells and platelets –Blood clot stops bleeding

22. 27-21 Bleeding Control (cont.) Thrombus – clot in a vessel with no known injury Embolus –Thrombus that breaks off and moves through blood stream –Danger of blocking artery Pulmonary embolism Myocardial infarction CVA

23. 27-22 Apply Your Knowledge ARTERIES: Hemostasis occurs to control bleeding. First the blood vessel spasms, then a platelet plug forms, and lastly, the blood coagulates forming a blood clot. Explain what happens when a blood vessel is injured?

24. 27-23 ABO Blood Types Blood types are distinguished by antigens and antibodies Agglutination –Clumping of red blood cells –Antigens on surface of RBCs bind to antibodies in plasma

25. 27-24 Blood Types (cont.)

26. 27-25 Blood Types (cont.) Blood TypeAntigen on RBC Antibody in Plasma Blood That Can Be Received AABA and O BBAB and O ABA and BNone A, B, AB, and O ONoneA and BO

27. 27-26 Apply Your Knowledge Identify the blood type: ANSWER: 1 4 3 2

28. 27-27 Rh Factor Rh antigen –Rh-positive –Rh-negative Transfused blood –Match for Rh factor –1 st unmatched transfusion ~ antibodies develop –2 nd time ~ agglutination

29. 27-28 Rh Factor Erythroblastosis fetalis –Mother developed antibodies to the Rh antigen in prior pregnancy –Antibodies attack fetus’ blood –Infant ~ severe anemia

30. 27-29 Rh Factor (cont.)

31. 27-30 Apply Your Knowledge ANSWER: Rh-positive blood contains the Rh antigen while Rh-negative blood does not. If a person with Rh- negative blood receives a transfusion of Rh-positive blood, he will develop antibodies to the Rh antigen. If he receives any subsequent transfusions of Rh- positive, agglutination will occur. What is the difference between Rh-positive and Rh-negative blood and why is it important to know whether a person is RH-positive or negative before transfusing blood? Bravo!

32. 27-31 Diseases and Disorders of the Blood System DiseaseDescription AnemiaThe blood does not have enough RBCs or hemoglobin to carry an adequate amount of oxygen to the body’s cells LeukemiaBone marrow produces a large number of abnormal WBCs Sickle cell anemia Abnormal hemoglobin causes RBCs to change to a sickle shape; abnormal cells stick in capillaries

33. 27-32 Diseases and Disorders of the Blood System (cont.) DiseaseDescription Polycythemia vera Disease of the bone marrow that results in an abnormally high number of blood cells, especially RBCs, causing the blood to thicken ThalassemiaInherited form of anemia; defective hemoglobin chain causes, small, pale, and short-lived RBCs

34. 27-33 Apply Your Knowledge ANSWER: Anemia is a condition in which a person does not have enough red blood cells or hemoglobin in the blood to carry an adequate amount of oxygen to body cells. The doctor has told your patient she has anemia. How would you explain this to her? Way to go!

35. 27-34 In Summary 27.1. The formed elements in blood include: red blood cells that are responsible for oxygen and carbon dioxide transport; white blood cells that are responsible for working with the immune system by fighting infection; and platelets, which assist in blood clotting. The liquid component of blood is called plasma and when all clotting factors and formed elements are spun out of plasma, the remaining liquid is called serum.

36. 27-35 In Summary (cont.) 27.2 Hemostasis refers to the control of bleeding. Three basic processes occur during hemostasis: 1. blood vessel spasm; 2. platelet plug formation; and 3. blood coagulation. Clot formation is coagulation. It involves fibrinogen converting to fibrin, which sticks to the damaged area of the blood vessel, creating a meshwork that entraps blood cells and platelets

37. 27-36 In Summary (cont.) 27.3 The four blood types are: A, B, AB and O. The antibodies attached to each type (except AB, which has no antibodies) require that each blood type receive only its specific antigen type during transfusions. So, A receives A or O; B receives B or O; AB as the universal receiver can receive any blood type; and O, although the universal donor, may receive only type O blood.

38. 27-37 In Summary (cont.) 27.4 Rh factor is an antigen that may be attached to any blood type. Its importance arises during transfusions (Rh- negative blood cannot receive Rh-positive blood) and also during pregnancy if the mother is Rh- negative but the fetus received the Rh-positive antigen from the father. The effect on the first fetus will be little, but unless treated, any subsequent Rh-positive fetus will suffer effects of erythroblastosis fetalis, as the mother’s blood developed antibodies against the Rh-positive factor during the initial pregnancy.

39. 27-38 In Summary (cont.) 27.5 There are many different types of blood diseases described within this chapter. The signs, symptoms, and treatments are as varied as the diseases themselves. The Common Diseases and Disorders for the Blood System section of this chapter outlines the most common of these diseases, their signs and symptoms, as well as their treatments.

40. 27-39 End of Chapter 27 The bond that links your true family is not one of blood, but of respect and joy in each other’s life. ~ Richard Bach