14 unit 1 chapter 14. 14 unit 1 transportation-hormones, gasses, nutrients, ions, heat regulation-...
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The Cardiovascular The Cardiovascular System: BloodSystem: Blood
The Cardiovascular The Cardiovascular System: BloodSystem: Blood
Chapter 14
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FunctionFunctionFunctionFunction
• Transportation-hormones, gasses, nutrients, ions, heat
• Regulation- pH, temperature, water balance in cells
• Protection- clotting, white cells interferons, complement
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CompositionCompositionCompositionComposition
• Connective tissue-Two parts• Plasma = soluble materials
(~55%)• Formed Elements = cells (~45%)• Percent occupied by red blood
cells (RBC) = hematocrit (Hct)• White blood cells (WBC) ~1%
Figure 14.1aFigure 14.1a
Figure 14.1bFigure 14.1b
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PlasmaPlasmaPlasmaPlasma
• ~91% water, 7% proteins, 1.5 % other solutes
• Proteins: Albumin (54%)- osmosis and carriers;
• Globulins (38%)- antibodies• Fibrinogen (7%)- clotting• Other: Electrolytes , nutrients,
gases, hormones, vitamins & waste products
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Formed ElementsFormed ElementsFormed ElementsFormed Elements
I. Red Blood CellsII. White blood cells
A. granular Leukocytes1. Neutrophils2. Eosinophils3. Basophils
B. Agranular leukocytes1. T & B lymphocytes & natural Killer cells2. monocytes
III Platelets
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Formation of Blood CellsFormation of Blood CellsFormation of Blood CellsFormation of Blood Cells
• Called hemopoiesis• Just before birth and throughout
life occurs in red bone marrow• Contains pluripotent stem cells• In response to specific
hormones these develop through a series of changes to form all of the blood cells
Figure 14.2aFigure 14.2a
Figure 14.2bFigure 14.2b
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Erythrocytes (RBCs)Erythrocytes (RBCs)Erythrocytes (RBCs)Erythrocytes (RBCs)
• Hemoglobin package- carries oxygenAlso carries some CO2
• Male has ~ 5.4 million cells/µl; Female has ~4.8 million
• membrane, no nucleus, flexible structure
• use glucose for ATP production to maintain ionic compositionNo mitochondria
• Wear out fast- live ~120 days
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RBC CyclingRBC CyclingRBC CyclingRBC Cycling
• cleared by macrophages (liver & Spleen)
• Fe- recycled in bone marrowCarried in blood on transferrin
• Heme bilirubin and excreted (bile)
• Globin A.A. recycled.
Figure 14.3Figure 14.3
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RBC SynthesisRBC SynthesisRBC SynthesisRBC Synthesis
• called erythropoiesis• From stem cells: hemocytoblasts• Released as reticulocytes
Mature to erythrocytes in 1-2 days
• Production & destruction is balanced
• Low O2 delivery (hypoxia)
• erythropoietin release (EPO) from kidney• Stimulates erythropoiesis
Figure 14.4Figure 14.4
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White Blood CellsWhite Blood CellsWhite Blood CellsWhite Blood Cells
• Defenses: phagocytes, antibody production and antibacterial action
• Phagocytes:Neutrophil- first respondersMonocytes macrophages (big eaters)Eosinophil- phagocitize antibody-antigen
complexes Involved in suppressing allergic responses
Basophil- intensify allergic reactions
• Immune response: T-cells, B-cells& natural killer (NK) cells
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WBC Life SpanWBC Life SpanWBC Life SpanWBC Life Span
• 5000-10,00 WBC /µl blood• Limited number of bacteria can be
eaten• Life span is a few days • During active infection may be hours• Leukocytosis= increased WBC
numbers response to stresses• Leukopenia = decreased WBC
numbers
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PlateletsPlateletsPlateletsPlatelets
• Myeloid stem cells megakaryocytes 2000 -3000 fragments = platelets
• Plug damaged blood vessels• Promote blood clotting• Life span 5-9 days
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HemostasisHemostasisHemostasisHemostasis
• Hemostasis = stationary blood• 1. Vascular reactions (spasm)
Response to damageQuick reduction of blood loss
• 2. platelet plug formationBecome sticky when contact damaged vessel
wall• 3. blood clotting (coagulation)
Series of chemical reactions involving clotting factors
• Clotting in unbroken vessel= thrombosis
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Coagulation Coagulation Coagulation Coagulation
• Extrinsic pathway common stepstissue factor(TF) from damaged cells 1
• Intrinsic Pathway common steps Materials “intrinsic” to blood 1
• 1. prothrombinase which causes• 2. prothrombin thrombin causes• 3. fibrinogen fibrin clot
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Clot Retraction & Vessel Clot Retraction & Vessel RepairRepair
Clot Retraction & Vessel Clot Retraction & Vessel RepairRepair
• Clot pugs ruptured area• Gradually contracts (retraction)• Pulls sides of wound together• Fibroblasts replace connective
tissue• epithelial cells repair lining
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Control MechanismsControl MechanismsControl MechanismsControl Mechanisms
•Fibrinolysis: dissolving of clot by activated plasmin enclosed in clot
• Clots can be triggered by roughness on vessel wall = thrombosis
• Loose clot = embolus and can block a small vessel = embolism
Figure 14.5Figure 14.5
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Blood TypesBlood TypesBlood TypesBlood Types
• Surface antigens- react with antibodies
• Divided into groups based on antigens> 24 blood groups and > 100
different antigens
• We will deal with ABO and Rh groups
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ABO GroupABO GroupABO GroupABO Group
• Two antigens = A & B• If have only A –type A• If have only B –type B• If neither then Type O• Blood usually has antibodies that can
react with antigense.g. anti-A antibody or anti-B antibody
• You don’t react with your own antigensThus: type A has anti-B and vice versa
Figure 14.6Figure 14.6
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Rh Blood GroupRh Blood GroupRh Blood GroupRh Blood Group
• Antigen discovered in rhesus monkey
• If have antigen- Rh+
• Normally don’t have antibodies• antibodies develop after the first
exposure from transfusion
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TransfusionsTransfusionsTransfusionsTransfusions
• If mismatched blood given antibodies bind to it and hemolyze cells
• Type AB has no AB antibodies so can receive any ABO type blood called Universal recipients
• Type O have neither antigen so can donate to any other ABO type called Universal donors
• Misleading because of many other blood groups that must be matched