BSC2086 A&P II Exam #2 Study Guide 1 Lesson 5-6: Blood Blood and the Cardiovascular System • Cardiovascular system consists of: o Pump – the heart o Conducting system – blood vessels o Fluid medium – blood Specialized fluid connective tissue Contains cells suspended in a fluid matrix Blood • Transports materials to and from cells • Contains: o Oxygen (O2) & carbon dioxide (CO2) o Nutrients o Hormones o Immune system components o Waste products • Important functions of Blood: o Transportation of dissolved substances o Regulation of pH & ions o Restriction of fluid losses at injury sites Clotting o Defense against toxins & pathogens WBCs o Stabilization of body temperature • Components of Whole Blood: o Plasma – fluid component Consists of: • Water • Dissolved plasma proteins • Other solutes o Formed elements – all cells & solidsBSC2086 A&P II Exam #2 Study Guide 2 • Three (3) Types of Formed Elements: o Red Blood Cells (RBCs) – Erythrocytes Transport oxygen o White Blood Cells (WBCs) – Leukocytes Part of the immune system o Platelets Cell fragments involved in clotting • Hemopoiesis: Process of producing formed elements o Created from myeloid & lymphoid stem cells • Fractionation: Process of separating whole blood for clinical analysis by centrifugation o Separated into plasma & formed elements o Buffy Coat: Thin coat of platelets & white blood cells found between RBC pellet and plasma • Three (3) General Characteristics of Blood: o 38ºC (100.4ºF) = normal temperature o High viscosity – 5 times more viscous than water Viscosity caused by dissolved proteins & formed elements o Slightly alkaline (basic) pH – 7.35-7.45 • Blood volume (liters) = 7% of body weight (kilograms) o Adult male – 5-6 liters (5.3-6.4 quarts) o Adult female – 4-5 liters (4.2-5.3 quarts) o Loss of 10% of blood volume will cause a decrease in blood pressure Plasma • Composition: o Makes up 50-60% of blood volume o More than 90% of plasma is waterBSC2086 A&P II Exam #2 Study Guide 3 o Extracellular fluids Interstitial fluid (IF) & plasma Materials plasma & IF exchange across capillary walls: • Water • Ions • Small solutes • Plasma Proteins o Albumins – 60% Transport substances like fatty acids, thyroid hormones, & steroid hormones o Globulins/Immunoglobulins – 35% Antibodies Transport Globulins: Small molecules • Hormone-binding proteins • Metalloproteins • Apolipoproteins (lipoproteins) • Steroid-binding proteins o Fibrinogen – 4% Inactive plasma protein Molecules that form clots & produce long, insoluble strands of fibrin o Other proteins – 1% Changing quantities of specialized plasma proteins Peptide hormones normally present in circulating blood • Insulin • Prolactin (PRL) • Glycoproteins o Thyroid Stimulating Hormone (TSH) o Follicle Stimulating Hormone (FSH) o Luteinizing Hormone (LH) o Origins of plasma proteins More than 90% made in liver Antibodies made my plasma cells – activated B lymphocytes Peptide hormones made by endocrine organs • Serum: Liquid part of a blood sample o Produced when dissolved fibrinogen has converted to solid fibrin (which is removed) o Serum lacks clotting proteins and Ca2+ They’re used up during the clotting process Red Blood Cells • RBCs make up 99.9% of blood’s formed elements o Average adult has 25 trillion RBCs (1/3 of all cells in human body) • Hemoglobin (Hb): The protein molecule that gives whole blood its color & functions to transport respiratory gases o Binds and transports oxygen & carbon dioxide o Normal hemoglobin (adult male) – 14-18 g/dL whole bloodBSC2086 A&P II Exam #2 Study Guide 4 1 dL = 100 o Normal hemoglobin (adult female) – 12-16 g/dL whole blood o Hemoglobin Structure Complex quaternary structure Four (4) globular protein subunits • 2 alpha subunits & 2 beta subunits Each with one molecule of heme Each heme contains one (1) iron ion • The iron ion… o Associates easily with oxygen (oxyhemoglobin HbO2) o Dissociates easily from oxygen (deoxyhemoglobin) o Fetal Hemoglobin: Strong form of hemoglobin found in embryos Takes oxygen from mother’s hemoglobin o Thalassemia: Inability to produce enough Hb subunits Causes reduction of RBC production and fragile/short lived RBCs Affects development & growth If severe, may require periodic blood transfusions or treatment by converting adult Hb fetal Hb with hydroxyurea or butyrate • Red Blood Cell Count: The number of RBCs in 1 microliter of whole blood o Males – 4.5-6.3 million o Females – 4.2-5.5 million • Hematocrit (Packed Cell Volume – PCV): Percentage of RBCs in centrifuged whole blood o RBC volume/total volume o Males – 40-54% o Females – 37-47%BSC2086 A&P II Exam #2 Study Guide 5 • Structure of RBCs o Small & highly specialized discs o Thin in middle & thicker at edge • Three (3) Important Effects of RBC Shape on Function: o High surface-to-volume ratio Quickly absorb & release oxygen o Discs form stacks called rouleaux Smooth the flow through narrow blood vessels o Discs bend & flex entering small capillaries 7.8 µm RBC passes through 4 µm capillary • Sickle Cell Anemia: Caused by mutation of an amino acid in beta chain of hemoglobin o Low oxygen cause mutated Hb to alter RBC shape, making it stiff & easily damaged o Change in shape also causes it to block narrow capillaries o Can be treated with the same methods used to treat thalassemia • Life Span of RBCs o Lack nuclei, mitochondria, and ribosomes o Can’t repair and utilizes anaerobic metabolism for energyBSC2086 A&P II Exam #2 Study Guide 6 o Last about 120 days o 1% of circulating RBCs wear out per day 3 million RBCs per second o Turnover & formation usually matched • Hemoglobin Conversion and Recycling o Macrophages of liver, spleen, & bone marrow monitor RBCs Engulf RBCs before membranes rupture (hemolyze) o Phagocytes break hemoglobin into components Globular proteins break down into amino acids Heme broken down to biliverdin – organic green-colored compound • Bad bruises look greenish because of biliverdin formation in blood-filled tissues • Biliverdin (green) converted to bilirubin (yellow) o
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