Transcript Blood
BLOOD Composition of Blood Plasma Formed elements BLOOD FUNCTIONS • TRASPORTATION OF OXYGEN, CARBON DIOXIDE, NUTRIENTS, HORMONES, HEAT AND WASTE. • REGULATION OF pH, BODY TEMPERATURE & WATER CONTENT • PROTECTION AGAINST DISEASE BY WHITE BLOOD CELLS & ANTIBODIES BOOD VOLUMES • RANGE OF BLOOD VOLUME IS 5 TO 6 LITERS • MEDICAL TERMS: – NORMOVOLEMIC: NORMAL BLOOD VOLUME – HYPOVOLEMIC: LOW BLOOD VOLUME – HYPERVOLEMIC: HIGH BLOOD VOLUME PHYSICAL CHARACTERISTICS • MEAN TEMPERATURE: 38C (100.4F) • VISCOSITY: PLASMA = 1.5 WHOLE BLOOD = 3 • MEAN pH: 7.35 to 7.45 PLASMA COLOR IS YELLOWISH COMPOSITION 91.5% WATER • 7% PROTEINS 1.5% OTHER SOLUTES PLASMA PROTEINS • ALBUMIN – 54% • GLOBULIN – 38% • FIBRINOGEN – 7% OTHER SOLUTES • • • • • • ELECTROLYTES NUTRIENTS ENZYMES HORMONES GASES WASTE PRODUCTS FORMATION OF FORMED ELEMENTS HEMOPOIESIS • IN RED BONE MARROW & LYMPH TISSUE • ALL BLOOD CELLS COME FROM PLURIPOTENT STEM CELLS THAT BECOME MYELOID OR LYMPHOID STEM CELLS. • LYMPHOID STEM CELLS PRODUCE THE WBC’s CALLED LYMPHOCYTES. • MYELOID STEM CELLS PRODUCE ALL THE REST (RBC’s, PLATELTES & THE OTHER FOUR WBC’s) RED BLOOD CELLS (RBC’s) (ERYTHOCYTES) • NUMBER: MALE = 5.4 MILLIONS/ uL FEMALE = 4.8 MILLIONS/ Ul • BICONCAVE DISCS, 7-8 um DIAMETER • NO NUCLEUS • EACH CONTAIN ONE HEMOGLOBIN MOLECULE, 4 HEME GROUPS AND 4 IRON IONS. RBC’s FUNCTIONS • HEMOGLOBIN TRANSPORT 97% OF OXYGEN. • HEMOGLOBIN TRANSPORT 23% OF CARBON DIOXIDE • HEMOGLOBIN PARTICIPATE IN THE REGULATION OF BLOOD FLOW BY RELEASING NITRIC OXIDE. HEMOGLOBIN • COMPOSED OF A PROTEIN PART CALLED GLOBIN AND FOUR IRON CONTAINING PARTS CALLED HEME. • EACH HEME BIND ONE OXYGEN MOLECULE. • HEMOGLOBIN BIND OXYGEN IN THE LUNGS AND RELEASE IT IN TISSUES. HEMOGLOBIN MOLECULE RBC’s FORMATION • CALLED ERYTHROPOIESIS • OCCUR IN RED BONE MARROW • HEMOGLOBIN SYNTHESIS OCCUR DURING DEVELOPMENT. • PROCEED THROUGH VARIOUS CELL STAGES AND TAKES ABOUT A WEEK. RBC’s DEVELOPMENT • • • • MYELOID STEM CELLS PROERYTHROBLASTS RETICULOCYTES ERYTHROCYES Requirements for RBC Formation *IRON *AMINO ACIDS *VITAMIN B12 – Supplied by diet and recycled from storage in liver and spleen – Free iron is toxic, so must combine with proteins to be stored or transported • Storage molecule is FERRITIN • Transport molecule is TRANSFERRIN STIMULATION OF RBC FORMATION • • • • • • • • • • DECREASED RBCs NUMBER ↓ TISSUE HYPOXIA ↓ ERYTHROPOIETIN HORMONE SECRETION BY THE KIDNEYS ↓ BONE MARROW STIMULATION ↓ PROERYTHROBLASTS → ERYTHROCYTES Recycling of RBC’s • RBC’s live for about 80 - 120 days • Death – Hemolysis in blood – Liver and spleen phagocytes consume them • Hemoglobin degraded to globin and heme – Amino acids of globin recycled – Heme split open releasing iron which is recycled – Heme → Biliverdin → Bilirubin in bile → urobilin in urine or stercobilin in feces RBCs RECYCLING White Blood Cells or Leukocytes • General functions: Protection by immune response or phagocytosis. • Whole count: 5000 – 10,000 / uL • Differential: Determining the percentage of each type of white blood cells. WBC’s TYPES & FUNCTIONS • GRANULAR: NEUTROPHILS, EOSINOPHILS AND BASOPHILS. • FUNCTION FOR PHAGOCYTOSIS AND INFLAMMATORY RESPONSE. • AGRANULAR: LYMPHOCYTES AND MONOCYTES. • FUNCTION IN ANTIGEN-ANTIBODY REACTIONS & AS MACROPHAGES. FORMATION OF WBC’s • LOCATION – RED BONE MARROW FOR MONOCYTES, NEUTROPHILS, BASOPHILS AND EOSINOPHILS. – LYMPH TISSUE FOR LYMPHOCYTES. DEVELOPMENTAL PATHWAYS • Leukocytes – Myeloid stem cells myeloblasts and monoblasts • Myeloblasts Neutrophils, Eosinophils and Basophils. • Monoblasts Monocytes – Lymphoid stem cells lymphoblasts • Lymphoblast lymphocytes Table of WBC’s Ranked by Differential WBC Function Differential NEUTROPHILS PRIMARY (POLYMORPHONU PHAGOCYTES. CLEOCYTE) (PMN) SEGMENTED NUCLEUS AND LAVENDER GRANULATER CYTOPLASM LYMPHOCYTES B-CELLS & T-CELLS IMMUNITY SPHERICAL NUCLEUS & BLUE CYTOPLASM MONOCYTES TISSUE MACROPHAGES KIDNEY-SHAPED OR OVAL NUCLEUS EOSINOPHILS PHAGOCYTOSIS OF PARASITES AND BILOBED NUCLEUS & RED GRANULES ANTINFLAMMATORY BASOPHILS HISTAMINE & INFLAMMATION BILOBED NUCLEUS & DARK GRANULES PLATELETS • THROMBOPOIETIN: FROM THE LIVER • FUNCTIONS: BLOOD CLOTTING AND PLATELTES PLUG FORMATION. • DEVELOPMENT: MYELOID STEM CELL > MEGAKARYOPLAST > MEGAKARYOCYTE > FRAGMENT INTO PLATELETS. • NUMBER: 150,000 – 400,000 / uL HEMOSTASIS RESPONSES THAT STOP BLEEDING (1) VASCULAR SPASM: CONTRACTION OF THE INJURED BLOOD VESSEL SMOOTH MUSCLES TO REDUCE THE BLOOD VESSEL DIAMETER AND DECREASE LOSS OF BLOOD. HEMOSTASIS (2) Platelet plug formation • Platelet adhesion _______________________ _______________________ • Platelet release reaction _______________________ _______________________ • Platelet aggregation _______________________ _______________________ HEMOSTASIS (3) CLOT FORMATION: • Clot closes the broken blood vessel. • Clot consists of a gel of fibrin and trapped formed blood elements. • When gel separates from liquid, remaining fluid is called serum. • Clotting process is called coagulation. • Blood clotting occurs in three stages – Stage 1. Formation of Prothrombinase – Stage 2. Formation of Thrombin – Stage 3. Formation of Fibrin plug (clot) • Formation of prothrombinase involves two pathways – Intrinsic pathway results from blood trauma • Damaged vessel • Damaged platelets • Slowest – Extrinsic pathway results from tissue trauma • Damage of cells outside blood • Fastest – Both pathways occur during normal clotting and produce Prothrombinase. Basic Steps in Blood Clotting Extrinsic Pathway Involves Tissue Trauma and Clotting Factors Intrinsic Pathway Involves Blood Trauma and Clotting Factors Ca2+ Ca2+ Prothrombinase Prothrombin Thrombin Ca2+ Thrombin Fibrinogen Fibrin (clot) CLOT DISSOLVING • As repair of a cut or damaged vessel proceeds, a series of enzyme catalyzed reactions called ___________ fibrinolysis slowly dissolves the clot • An enzyme called _______________________ tissue plasminogen activator catalyzes the conversion of inactive enzyme plasminogen to active_________ plasmin ___________ • Active enzyme catalyzes the dissolving of clot CLOT DISSOLVING Plaminogen Tissue plasminogen activator Plasmin INTRAVASCULAR CLOT • • • • • • Intravascular clot – clot within closed vessel Damaged vessel lining or slowing of blood flow Platelets aggregate and release clotting factors thrombus Resulting clot called a _________ Moving piece of the clot is an ________ embolus Clot moves downstream and blocks smaller vessel embolism _________ • May cut off blood supply to organ ANTICOAGULANTS • Chemicals that decrease or prevent blood clotting are called ____________ anticoagulants • Heparin is administered medically and it occurs naturally in our bodies. It works by decreasing thrombin production • Coumadin (warfarin) is effective as a long-term anticoagulant. It is an antagonist of vitamin K. • EDTA and CPD are used in blood banks to keep the donated blood from clotting. They both work by tying-up and removing calcium. BLOOD TYPES • ABO and Rh • Antigens (glycoproteins and glycolipids) called ____________ agglutinogens on surface of RBC’S determine blood types. • Blood types are inherited • The greatest concern with blood types involves ___________ transfusions • During a transfusion, the person giving the donor the person getting the blood is a ______, blood is a ________ recipient • The immune system may develop antibodies called __________ agglutinins against certain agglutinogens. These agglutinins float in the plasma. • If RBC’s of a donor are incompatible with the blood of a recipient, agglutinins in the plasma of the recipient will bind to the agglutinogens of the clump donated RBC’s. This reaction will ______ (_________) agglutinate and destroy (cause hemolysis of) the donated RBC’s, causing a serious and possibly fatal reaction. ABO BLOOD TYPES ABO Type Antigen Antibodies Acceptable on in Plasma Transfusion RBC’s A B AB O A B A&B Neither Anti-B Donate to A & AB Receive from A&O Anti-A Donate to B&AB Receive from B&O Neither Donate to only AB Receive from O Both Donate to A,B,AB&O Receive from only O Rh blood type and hemolytic disease of the newborn • Rh blood type is determined by presence of agglutinogens (________) antigens absence of Rh _____________ on the surface of RBC’s • If Rh agglutinogens are present, the type is + Rh . If no -agglutinogens are present, the type is Rh . • People with Rh- type lack anti-Rh agglutinins (antibodies), but if they receive Rh+ blood, their immune systems will be stimulated to produce them, and they are then _________. sensitized Future exposure to Rh+ blood will cause a dangerous blood reaction. Hemolytic Disease of the Newborn (HDN) • Results from Rh incompatibility between ___ Rh- mother and her ____child Rh+ • If Rh+ RBC’s of first born child enter mother’s circulation, mother will be __________, sensitized and her plasma will carry antiRh agglutinins (antibodies) • The first child is not harmed, but the agglutinins acquired by mother’s ____________, exposure to the first child’s blood, easily pass across the placenta where they agglutinate ___________and destroy the second child’s RBC’s. Hemolytic Disease of the Newborn CLINICAL TERMS • Polycythemia: High RBC’s number. • Anemia: Low RBC’s number. • Leukemias: High WBC’s number diseases. • Leukopenia: Low WBC’s number. Clinical Terms Continued • Leukocytosis: High WBC’s number. • Hemophilia: Lack of blood coagulation. • Thrombocytopenia: Low platelets number. • Sickle cell disease: Abnormal RBC’s form • Jaundice: bilirubin leak in the blood.