Blood functions: a. Distributive - Delivers oxygen and nutrients to all cells - carries metabolic wastes to elimination sites - carries hormones to target organs - maintains body temperature; absorbs & distributes heat b. Protective - maintains normal pH of tissues - maintains circulatory volume - prevents blood loss - combats infection

Physical characteristics of blood Viscosity = Temperature = 38 0 C F ph = NaCl concentration =.85%-.90% Total body weight = 8% Volume = 4-5 L women, 5-6 L men

Hematopoiesis (Hemopoiesis) - blood cell formation Occurs in: - myeloid tissue erythrocytes (rbc) all granulocytes (wbc). neutrophils, eosinophils, basophils one agranulocyte (wbc). monocytes thrombocytes (platelets) - lymphoid tissue one agranulocyte (wbc). lymphocytes

Erythrocyte disorders: - Anemias = reduced O 2 carrying ability due to few RBCs.. Hemorrhagic. Megaloblastic (pernicious anemia). Hemolytic * Sickle Cell. Aplastic - Polycythemia. Blood doping

Leucocyte disorders: - leukemia = cancerous condition of WBC. acute. chronic - infectious mononucleosis = elevated white count, Epstein-Barr virus

Blood coagulation: 50+ substances in blood involved in coagulation. Categorized as either: Procoagulants Anticoagulants Mechanisms of coagulation: 1.Rupture of vessel initiates a series of chemical reactions that produce a complex called prothrombin activators 2.Prothrombin activators cause the conversion of prothrombin into thrombin. 3.Thrombin causes fibrinogen to convert into fibrin fibers Innate immunity: integument, tissue macrophages, stomach acids Acquired immunity: formation of antibody response, activated T cells