A&P Blood

  1. Blood Composition
    Specialized type of connective tissue...formed elements (RBCs, WBCs, and platelets) in plasma

    Bright scarlet to dull brick deending on its oxygen content

    Slightly alkaline (pH 7.35 to 7.45)

    8% of body weight (5 liters in average adult)
  2. Blood Plasma (non-living matrix)
    55% of blood, liquid containing dissolved substances
  3. Blood Plasma Composition
    90% water

    Most abundant solute = plasma proteins (albumin, globulins, fibrinogens)

    • 100 differennt dissolved solutes:
    • Non-protein nitrogenous substances
    • Organic nutrients
    • Electrolytes
    • Respiratory gases
    • Serum = fluid after clotting
  4. Blood Formed Elements (living cells)
    45% of blood, all develop from a common precursor cell
  5. Blood Functions
    • Distribution
    • Regulation
    • Protection
  6. Blood Distribution
    Delivers oxygen from lungs to body cells and nutrients from GI tract

    Transports metabolic wastes from cells to elimination sites

    Transports hormones from endocrine glands to targets
  7. Blood Regulation
    • Maintains body temperature
    • Maintains normal pH (using buffers)
    • Maintains fluid volume
  8. Blood Protection
    Prevention of blood loss (hemostasis: vascular spasm, platelet plug formation, coagulation)

    Prevents infection through antibodies, complement proteins and WBCs
  9. Formed Element Types
    • RBCs
    • WBCs
    • Platelets
  10. Erythrocytes (RBCs) Structure
    Flexible biconcave anucleate disc

    7 to 7.5 microns

    Mature RBCs are "bags" of hemoglobin (for RBC function)
  11. Hematocrit
    Measurement of the percentage of RBCs in the blood
  12. Erythrocytes (RBCs) Function
    • Transport oxygen and carbon dioxide
    • RBC maturation requires hemoglobin formation
  13. Hemoglobin Formation
    Composed of globin (4 polypeptide chains) and heme (red pigment containing iron)

    Oxyhemoglobin - oxygen saturated, red color

    Deoxyhemoglobin - no oxygen, bluish color

    Carbaminohemoglobin - carbon dioxide bound to globin
  14. Erythrocytes Life Cycle (120 days) -Production & Destruction
    Production (erythropoiesis) - occurs in the bone marrow of certain bones, regulated by oxygen content of arterial blood, involves hormone erythropoietin produced in kidneys

    Destruction: RBCs cannot make new proteins so they age and can no longer function and break down
  15. Erythrocytes Disorders
    • Anemias
    • Polycythemia
  16. Anemia
    Anemias: blood has a low oxygen carrying ability:

    • Hemorrhagic anemia
    • Hemolytic anemia
    • Aplastic anemia
    • Iron-deficiency anemia
    • Pernicious anemia
    • Sickle-cell anemia
  17. Polycythemia
    Abnormal excess of erythrocytes increasing viscosity (thickness) of blood
  18. Hemorrhagic Anemia (causes, symptoms, treatment)
    Insufficient number of RBC

    Causes: blood loss

    Symptoms: blood loss, excessive RBC destruction, bone marrow failure

    Treatments: blood replacement
  19. Hemolytic Anemia (causes, symptoms, treatment)
    Insufficient number of RBCs

    Causes: hemoglobin abnormalities, transfusion of mismatched blood, certain bacterial and parasitic infections

    Symptoms: erythrocytes rupture or lyse prematurely

    Treatments: blood replacement
  20. Aplastic Anemia (causes, symptoms, treatments)
    Insufficient number of RBCs

    Causes: destruction or inhibition of the red marrow by certain drugs and chemicals, ionizing radiation, viruses, mostly unknown

    Symptoms: marrow deconstruction, defects in blood clotting and immunity

    Treatments: blood transfusions
  21. Iron-Deficiency Anemia (causes, symptoms, treatment)
    Low hemoglobin content

    Causes: secondary result of hemorrhagic anemias, inadequate intake of iron-containing foods, impaired iron absorption

    Symptoms: erythrocytes produced (microcytes) are small and pale

    Treatment: iron supplements, red cell transfusions
  22. Pernicious Anemia (causes, symptoms, treatments)
    Low hemoglobin content

    Causes: deficiency of vitamin B12

    Symptoms: intrinsic factor is deficient (erythrocytes grow but don't divide and macroctyes result), stomach mucosa atrophies

    Treatments: Intramuscular injections of vitamin B12 or application of a B12 containing gel (Nascobal) to the nasal lining
  23. Sickle-Cell Anemia (causes, symptoms, treatments)
    Abnormal hemoglobin

    Causes: a change in one of the 146 amino acids in a beta chain of the globin molecule

    Symptoms: deformed erythrocytes that rupture easily and dam up in small blood vessels, loss of oxygen delivery, bone and chest pain, infection and stroke

    Treatments: blood transfusion
  24. Leukocytes (WBCs) Structure
    • Spherical nucleated cells
    • True cells with usual organelles
    • Less numerous then RBCs
  25. Leukocytes (WBCs) Function
    • Defense against disease
    • Each type has a specific function
  26. Leukocytes - Production & Life Span
    Production: in bone marrow

    Short life span: 4-5 days, to hours if severe infection
  27. Leukocytes Disorders
    • Leukemia
    • Infectious mononucleosis
  28. Platelets Structure
    Discord cytoplasmic fragment of megakaryocytes (large multinucleated cells formed in bone marrow)

    No nucleus
  29. Platelets Function
    Essesntial role in blood clotting

    Motile, store and release chemicals with a life span of 10-14 days
  30. Never Let Monkeys Eat Bananas (Leukocytes)
    Neutrophils, lymphocytes, monocytes, eosinophils, basophils
  31. Neutrophil
    Most abundant of WBCs (50-70% of pop), mutilobed nucleus, phagocyte, acute infections
  32. Eosinophil
    Bilobed nucleus, red cytoplasmic granules, 2-4% of pop, counterattack parasitic worms, allergy and asthma
  33. Basophil
    Bilobed nucleus, purplish-black cytoplasmic granules, less than 1% of pop, histamine
  34. Lymphocyte
    Smallest of leukocytes, 25% or more of pop, immunologic responses

    B lymphocytes: plasma cells that produce antibodies released to blood

    T lymhocytes: regulatory role and destroys grafts, tumors, and virus-infected cells
  35. Monocyte
    Largest of leukocytes, 3-8% of pop, convert to macrophages, active phagocytes, chronic infections such as tuberculosis
  36. Homeostasis Overview - Stopping of bleeding
    Vital to body because hemorrhage is life-threatening

    Blood vessels, platelets and coagulation factors important for clotting

    Involves positive feedback mechanism

    After blood vessel has healed clot is lysed
  37. Homeostasis Events
    • Vascular spasm
    • Platelet plug formation
    • Coagulation
  38. Homeostasis - Vascular Spasm
    Constriction of damaged blood vessel, narrows diameter

    Vessel injury exposes CT, stimulating platelets and coagulation factors
  39. Homeostasis - Platelet plug formation = temporary seal
    Platelets aggregate and adhere to injure site

    Platelets release vasoconstrictors, narrow vessel more

    Platelets release phospholipid that initiates phase three if necessary (small caps plug, larger vessels need clot formation)
  40. Homeostasis - Coagulation = blood clot formation
    Coagulation factors are activated and manufactored in liver

    A chain reaction

    All phases need calcium ions (3 phases):

    • Prothrombin activator produced by two different
    • mechanisms: intrinsic and extrinsic

    Conversion of prothrombin (factor II) to thrombin by activator made in phase I

    Conversion of fibrinogen (factor I) to fibrin by thrombin made in phase II

    Clot retraction and vessel repair
  41. Fibrinolysis
    Removal of unneeded clot
  42. Homeostasis - Factors Limiting Clot Growth or Formation = homeostatic mechanisms
    Swift removal of clotting factors

    • Inhibition of activated clotting factors:
    • Heparin - natural anticoagulant
  43. Homeostasis - Disorders
    Hemophilias - hereditary bleeding disorders
  44. Intrinsic Vs. Extrinsic
    Intrinsic: minutes, factor 10, Ca2+, prothrombin - thrombin, fribrinogen, fibrin

    Extrinsic: seconds, tissue factor, Ca2+, prothrombin - thrombin, fribrinogen, fibrin
  45. Transfusion and Blood Replacement
    Loss of 30% of blood volume can be fatal

    Blood transfusion can be routinely done but people have different blood types and transfusion of incompatible blood can be fatal
  46. Transfusion and Blood Replacement - Human Blood Groups
    Bases on presence of unique antigens on RBC membrane

    Antigens (aggulations) are proteins that cause formation of antibodies and promote agglutination or clumping

    • Major groups subject to blood typing:
    • ABO grouping
    • Rh blood grouping and hemolytic disease of the newborn or erythroblastosis fetalis
  47. Transfusion and Blood Replacement - Transfusion Reactions
    Donor's RBC are attacked by the recipient's plasma agglutinins

    • 1. Universal donor = type O
    • 2. Universal recipient = type AB
  48. Transfusion and Blood Replacement - Diagnostic Blood Tests
    • CBC = complete blood count
    • Blood chemistry profile
Card Set
A&P Blood
A&P Blood