Bio 314 Exam 1

  • Many myths about blood

    • Mysterious “vital force”

    • Drained “bad-blood” for medical reasons

    • Hereditary traits were once thought to be transmitted through blood

  • Blood cells were seen with the first microscopes

  • ___Hematology —the study of blood

  • Circulatory system consists of the heart, blood vessels, and blood

  • Cardiovascular system refers only to the heart and blood vessels

  • Functions of the Circulatory system

    • Transport

      • O2, CO2, nutrients, wastes, hormones, and stem cells

    • Protection (leukocytes)

      • Inflammation, limit spread of infection, destroy microorganisms and cancer cells, neutralize toxins, and initiate clotting

    • Regulation

      • Fluid balance, stabilizes pH of ECF, and temperature control

  • Adults have 4 to 6 L of blood

  • A liquid connective tissue consisting of cells and extracellular matrix

    • ___plasma_____________: matrix of blood

      •  Clear, light yellow fluid

    • ___Formed elements____________: blood cells and cell fragments

      •  Red blood cells, white blood cells, and platelets

    • Seven kinds of formed elements

      • 1) __Erythrocytes______________: red blood cells (RBCs)

      • 2) __Thrombocytes______________: Platelets

        • Cell fragments from special cell in bone marrow

  • Leukocytes: white blood cells (WBCs)

    • Five leukocyte types divided into two categories

    • _Granulocytes_______________ (with granules)

      • 3)Neutrophils

      • 4)Eosinophils

      • 5)Basophils

    • ___Agranulocytes_______________ (without granules)

      • 6)Lymphocytes

      • 7)Monocytes

  • _Hematocrit________________ —centrifuge blood to separate components

    • Erythrocytes are heaviest and settle first

      • 37% to 52% total volume

    • White blood cells and platelets

      • 1% total volume

      • ___Buffy coat_____________

    • Plasma

      • The remainder of volume

      • 47% to 63%

      • Complex mixture of water, proteins, nutrients, electrolytes, nitrogenous wastes, hormones, and gases

  • Plasma —liquid portion of blood

    • Serum: remaining fluid when blood clots and solids are removed

      • Identical to plasma except for the absence of fibrinogen

  • Three major categories of plasma proteins

    • _________________: smallest and most abundant

      • Contribute to viscosity and osmolarity; influence blood pressure, flow, and fluid balance

    • Globulins (antibodies) 

      • Provide immune system functions

      • Alpha, beta, and gamma globulins

    • __________________ 

      • Precursor of fibrin threads that help form blood clots

  • Plasma proteins are formed by liver 

    • Except globulins (produced by ___plasma cells _________________)

  • Nitrogenous Compounds of Blood Plasma

    • Free amino acids from dietary protein or tissue breakdown

    • Nitrogenous wastes (urea)

      • Toxic end products of catabolism

      • Normally removed by the kidneys

  • Nutrients of Blood Plasma

    • Glucose, vitamins, fats, cholesterol, phospholipids, and minerals

  • Gases of Blood Plasma

    • Dissolved O2, CO2, and nitrogen

  • Electrolytes of Blood Plasma

    • Na+ makes up 90% of plasma cations

  • __Viscosity__________________ —resistance of a fluid to flow, resulting from the cohesion of its particles

    • Whole blood 4.5 to 5.5 times as viscous as water

    • Plasma is 2.0 times as viscous as water

      • Important in circulatory function

  • Osmolarity of blood —the total molarity of those dissolved particles that cannot pass through the blood vessel wall

    • If too high, blood _absorbs____________________ too much water, increasing the blood pressure

    • If too low, too much water stays in tissue, blood pressure drops, and edema occurs

    • Optimum osmolarity is achieved by the body’s regulation of sodium ions, proteins, and red blood cells

  • Adult production of 400 billion platelets, 100-200 billion RBCs, and 10 billion WBCs every day

  • __Hemopoeisis_____________________ — production of blood, especially its formed elements

  • Hemopoietic tissues produce blood cells

    • __Yolk Sac___________________produces stem cells for first blood cells

      • Colonize fetal bone marrow, liver, spleen, and thymus

    • Liver stops producing blood cells at birth

    • Spleen remains involved with lymphocyte production

  • Red bone marrow produces all seven formed elements

    • Multipotent stem cells – many kinds

      • Specifically called _hemocytoblasts___________________ or hemopoietic stem cells

    • Colony-forming unit —specialized stem cells only producing one class of formed element of blood

    • Myeloid hemopoiesis —blood formation in the bone marrow

    • Lymphoid hemopoiesis —blood formation in the lymphatic organs (beyond infancy this only involves lymphocytes)