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Blood. Chapter 14. Online Tutorials on RBC, WBC. http://www.wisc-online.com/objects/ViewObject.aspx?ID=AP14604 http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap14704. What is blood?. The only fluid tissue Transport Oxygen and nutrients Waste Hormones
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Blood Chapter 14
Online Tutorials on RBC, WBC • http://www.wisc-online.com/objects/ViewObject.aspx?ID=AP14604 • http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap14704
What is blood? • The only fluid tissue • Transport • Oxygen and nutrients • Waste • Hormones • Maintains stability of interstitial fluid • Distributes heat
Components of Blood • Whole Blood – includes formed elements and matrix • Formed elements • Living blood cells • Platelets • Nonliving fluid matrix • Plasma
Centrifuge Blood • Plasma • Buffy coat • Red blood cells
Measuring Blood Samples • Usually 45% red blood cells • Hematocrit (HTC) • Packed cell volume (PCV) • White blood cells and platelets – less than 1% • Clear, straw colored liquid = plasma
What is in plasma? • Mostly water • Also contains (every other molecule found in the human body…) • Amino acids • Protein • Carbohydrates • Lipids • Vitamins • Hormones • Electrolytes • Cellular waste
Physical Characteristics of Blood • Can vary in color from scarlet (oxygen rich) to dull red (oxygen poor) • pH between 7.35 and 7.45 • Average temperature 100.4°C • Average human has about 5-6 liters of blood
The origin of Blood Cells • Hematopoiesis • From hematopoietic stem cells (hemocytoblasts) • Hematopoietic stem cells can differentiate into myeloid stem cells OR lymphoid stem cells • Determined by hematopoietic growth factors
Formed Elements • Erythrocytes • Leukocytes • Granulocytes: • Neutrophils • Eosinophils • Basophils • Agranulocytes • Lymphocytes • Monocytes • Platelets
Erythrocytes • Red blood cells (RBCs) • Transport of oxygen throughout body • Anucleate • Few organelles • Hemoglobin • Iron-bearing compound • Binds to oxygen
Erythrocytes • Efficient oxygen carriers • Biconcave shape • Increases surface area • Can easily pass through small blood vessels • Synthesis of ATP is anaerobic • Over time, blood cells become rigid, damaged • Removal by spleen and liver
Red Blood Cell Formation • Use your textbooks to answer the following questions: • Where does it occur? • What happens to form a mature red blood cell from a hematopoietic stem cell? • What hormones are involved? • How long can red blood cells live?
Factors Affecting Red Blood Cell Formation • Vitamin B12 • Folic Acid • Both are required in DNA synthesis, mitosis • Iron – hemoglobin synthesis
Anemia • Decrease in oxygen carrying ability of the blood • Can be caused by • Abnormally low number of RBCs • Abnormal/deficient hemoglobin • Symptoms: • Pale skin • Lack of energy
Destruction of Red Blood Cells • Damaged or worn blood cells rupture in spleen and liver • Macrophages phagocytize RBC • Cell parts are broken down • Hemoglobin breaks into 4 globin chains • Globin chains break down into iron and biliverdin (green) • Iron will be transferred (via transferrin) to the red marrow to be recycled • Biliverdin is converted into bilirubin (orange) • Biliverdin and bilirubin are excreted in bile
Leukocytes • White blood cells (WBCs) • Much less numerous than red blood cells • Body’s defense against disease • Contain nuclei, organelles • 2 groups: granulocytes, agranulocytes
Granulocytes • Leukocytes with granular cytoplasm • About 2x the size of a RBC • Neurophils • Eosinophils • Basophils • Develop in red marrow • Life span approx. 12 hours
Neutrophils • Look purple with an acid/base stain • Nucleus lobed (2-5 sections) • First to arrive at infection site • Phagocytosis of bacteria, fungi, some viruses • 54% - 62% of leukocytes
Eosinophils • Granules appear deep red in acid stain • Two lobe nucleus • Allergic reactions, parasitic invasion • 1% - 3% of total number of leukocytes
Basophils • Fewer, irregular shaped granules than eosinophyls • Deep blue in basic stain • Migrate to damaged tissue in response to • Histamine (promotes inflammation) • Heparin (inhibits blood clotting) • Less than 1% of leukocytes
Agranulocytes • Leukocytes without cytoplasmic granules • Includes: • Monocytes • Formed in red marrow • Lymphocytes • Formed in organs of the lymphatic system
Monocytes • Largest blood cell • Nuclei are spherical, kidney shaped or oval • Leave blood stream and become macrophages • Phagocytize bacteria, dead cells, other debris in tissues • 3% - 9% of leukocytes • Live for weeks - months
Lymphocytes • Large nucleus with small amount of cytoplasm • Immune cells • T cells • Directly attack microorganisms, tumors, transplanted cells • B cells • Produce antibodies • 25% - 33% of leukocytes • Live for years
Functions of WBC • Diapedesis: leave blood vessels • Most active: neutrophils, monocytes • Damaged cells release chemicals to attracte leukocytes • Positive chemotaxis • Forms pus – accumulation of WBC
White Blood Cell Counts • High count may indicate infection • Leukocytosis – number of WBC exceeding 10,000 per microliter • Leukopenia • Low WBC count • Below 4,500 per microliter • May be caused by influenza, chicken pox, AIDS • Differential White Blood Cell Count (DIFF) • Allows type of cell to be counted – different diseases increase/decrease different WBCs
Platelets • Thrombocytes • Arise from megakaryocytes • Fragment and form platelets • No nucleus • Repair broken blood vessels by sticking to one another • Release of serotonin – blood vessel constriction
Quick Review • Another name for white blood cells. • Three types: Neurophils, Eosinophils, Basophils • Cells responsible for allergic reactions, parasitic invasion
Quick Review • Migrate to damaged tissue in response to histamine and heparin • Also known as thrombocytes, arise from megakaryocytes
Quick Review • Type of immune cell that produces antibodies • Type of immune cell that is involved in the direct attack of invaders.
Quick Review • First to arrive at infection site • Phagocytosis of bacteria, fungi, some viruses • Leave blood stream and become macrophages • Phagocytize bacteria, dead cells, other debris in tissues
Blood Plasma • Clear • Straw-colored • 92% water • Functions: • Transport of nutrients, gases, vitamins • Regulate fluid and electrolyte balance • Maintain pH
Plasma Proteins • Albumens • Globulins • Fibrinogen
Albumins • 60% of plasma proteins • Synthesized by the liver • Osmotic pressure • Amount of dissolved solute will determine water movement between blood and tissues • Transport of bilirubin, fatty acids, hormones
Globulins • 36% of plasma proteins • Alpha globulins, beta globulins – synthesized by the liver; transport lipids and fat-soluble vitamins • Gamma globulins – produced by the lymphatic system; type of antibody
Fibrinogen • 4% of plasma proteins • Largest plasma protein • Made in the liver • Role in blood coagulation
Hemostasis • Stoppage of bleeding • Three parts: • Blood vessel spasm • Platelet plug formation • Blood coagulation • Occurs in smaller blood vessels
Blood Vessel Spasm • Cutting a blood vessel results in smooth muscle within the wall of the vessel to contract (vasospasm)
Platelet Plug Formation • Platelets adhere to any rough surface • Especially collagen of connective tissue lining blood vessels • Platelets will change shape to assist in adhering to other platelets • Platelet plug will limit blood loss
Blood Coagulation • Blood clotting • Series of reactions form clot • Cascade • Extrinsic (broken blood vessels, tissue damage) • Intrinsic (blood contact with foreign substance in the absence of tissue damage) • Blood coagulation requires different blood clotting factors
Hemostasis • Complete the hemostasis worksheet using your textbooks. • Page 539 – 543 • Old book: