📘 Chapter 19: Blood – Full Simplified Study Notes (27 Slides)
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Slide 1: Cardiovascular System
• Cardiovascular system = heart, blood, blood vessels.
• Blood’s job:
• Delivers nutrients, hormones, oxygen, and chemical messages.
• Carries immune cells to fight infections.
• Why it matters: Without this transport system, cells would starve and toxins would build up.
• Analogy: Like UPS + garbage service → delivers packages (nutrients, O₂) and removes trash (waste, CO₂).
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Slide 2: Whole Blood
• Whole blood = plasma + formed elements.
• Hematocrit: percentage of blood volume made of cells.
• Plasma: watery fluid.
• Key properties of blood:
• Temp: 38°C (100.4°F) → warmer than body surface.
• Thickness: 5x thicker than water.
• pH: ~7.4 (slightly alkaline).
• Volume: Men = 5–6 L, Women = 4–5 L.
• About 7% of body weight.
• Example: If someone weighs 150 lbs, about 10 lbs of that is blood.
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Slide 3: Blood Plasma
• Plasma = liquid with proteins + solutes.
• Proteins:
• Albumins: keep water inside blood vessels (prevent swelling).
• Globulins: antibodies → defense.
• Fibrinogen: forms clots.
• Other solutes:
• Electrolytes: Na⁺, K⁺, Cl⁻, HCO₃⁻ (important for nerves/muscles).
• Nutrients: glucose, fructose, amino acids.
• Wastes: urea, uric acid.
• Analogy: Plasma = soup broth carrying salt, sugar, proteins, and waste.
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Slide 4: Formed Elements
• Red Blood Cells (RBCs / erythrocytes): 99.9% of all blood cells.
• RBC count: Men = 4.5–6.3 million/μL, Women = 4.2–5.5 million/μL.
• Platelets: fragments needed for clotting.
• White Blood Cells (WBCs / leukocytes): fight disease.
• Think: Plasma is the liquid, formed elements are the “stuff floating inside.”
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Slide 5: RBC Structure
• RBCs lose their nucleus & organelles.
• Consequences:
• Can’t divide.
• Can’t make proteins or repair.
• Only use glycolysis (anaerobic metabolism) → no oxygen needed for energy.
• Analogy: Like delivery trucks with no engine shop → they drive until they break down.
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Slide 6: RBC Lifespan
• RBCs have no nucleus, mitochondria, ribosomes → no repair.
• Rely on glycolysis for energy.
• Live about 120 days.
• Must be recycled by spleen/liver.
• Example: Like a disposable battery that runs until it dies.
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Slide 7: RBC Shape & Function
• Shape = biconcave disc (doughnut-like, thin middle).
• Benefits:
• High surface area → better oxygen exchange.
• Can stack like coins → smooth flow.
• Flexible → squeeze through tiny capillaries.
• Analogy: Like a flexible frisbee that can bend and stack.
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Slide 8: Hemoglobin
• Main protein inside RBC.
• Structure:
• 2 alpha chains + 2 beta chains.
• Each has heme group with iron atom (Fe).
• Function: Iron binds oxygen → carries it around body.
• Why recycle? Iron is valuable, so old RBCs get broken down to save it.
• Analogy: Hemoglobin = oxygen backpack.
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Slide 9: RBC Lifecycle
• Starts from hemocytoblast (stem cell).
• Branches into:
• Myeloid stem cells: make RBCs + some WBCs.
• Lymphoid stem cells: make lymphocytes.
• Think: Hemocytoblast = tree trunk, RBCs and WBCs = branches.
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Slide 10: RBC Production (Erythropoiesis)
• Erythropoiesis = making RBCs.
• Embryo: 1st 8 weeks = yolk sac → later liver, spleen, thymus, bone marrow.
• Adult: red bone marrow only (vertebrae, sternum, ribs, skull, pelvis, ends of long bones).
• Nutrients needed: amino acids, iron, vitamins B12, B6, folic acid.
• Analogy: RBCs = cookies, bone marrow = kitchen, iron + vitamins = ingredients.
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Slide 11: RBC Production Control
• Controlled by erythropoietin (EPO).
• Made by kidneys/liver when low oxygen (hypoxia).
• Effects:
• Increases stem cell division.
• Speeds up hemoglobin production.
• Blood doping: Athletes take EPO or reinfuse RBCs → more oxygen for muscles.
• Risk: thicker blood → clots, strokes.
• Analogy: EPO = coach yelling “make more RBCs!”
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Slide 12: Blood Types
• RBCs have antigens on membranes (A, B, AB, O).
• Rh factor = + or –.
• Plasma has antibodies (agglutinins): attack foreign antigens → cause clumping (agglutination).
• Universal donor = O–.
• Analogy: Blood type = ID card. If ID doesn’t match, antibodies attack.
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Slide 13: RBC Summary
• Know:
• How typing works.
• How RBCs are made.
• What controls them.
• Why they live 120 days.
• How they’re broken down.
• Analogy: RBCs = delivery trucks with expiration dates.
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Slide 14: WBC Basics
• WBCs = leukocytes.
• Have nuclei, organelles, no Hb.
• Functions: fight pathogens, remove wastes, destroy abnormal cells.
• Only in blood briefly → then move into tissues.
• Analogy: WBCs = body’s police force.
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Slide 15: Neutrophils
• 50–70% of WBCs.
• Nucleus 2–5 lobes.
• First responders → attack bacteria.
• Use phagocytosis + enzymes.
• Die quickly → pus = dead neutrophils + bacteria.
• Analogy: Neutrophils = foot soldiers.
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Slide 16: Basophils
• <1% WBCs.
• Release histamine (dilates vessels, causes swelling/redness).
• Release heparin (prevents clots).
• Trigger inflammation → work with mast cells.
• Analogy: Basophils = fire alarms.
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Slide 17: Eosinophils
• 2–4% WBCs.
• Stain red-orange.
• Bi-lobed nucleus.
• Kill parasites, respond to allergies.
• Release toxic chemicals (nitric oxide, enzymes).
• Help control inflammation.
• Analogy: Eosinophils = exterminators.
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Slide 18: Monocytes
• 2–8% WBCs.
• Largest WBC, kidney-shaped nucleus.
• Become macrophages in tissue.
• Eat large pathogens, dead cells.
• Call fibrocytes → scar tissue.
• Analogy: Monocytes = garbage trucks.
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Slide 19: Lymphocytes
• 20–30% WBCs.
• Big nucleus, little cytoplasm.
• Most live in lymph tissue.
• Types:
• T cells: attack infected cells.
• B cells: make antibodies.
• NK cells: kill cancer/virus cells.
• Analogy: Lymphocytes = special forces.
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Slide 20: WBC Production
• From hemocytoblasts.
• Myeloid stem cells: all except lymphocytes.
• Lymphoid stem cells: lymphocytes.
• Colony-Stimulating Factors (CSFs):
• M-CSF = monocytes.
• G-CSF = granulocytes.
• GM-CSF = granulocytes + monocytes.
• Multi-CSF = RBCs + WBCs + platelets.
• Analogy: CSFs = managers assigning jobs.
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Slide 21: Platelets
• Fragments of cells, no nucleus.
• Lifespan = 9–12 days.
• Removed by spleen.
• 2/3 stored for emergencies.
• Analogy: Platelets = emergency patch kits.
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Slide 22: Platelet Functions
1. Release clotting chemicals.
2. Form platelet plug at damage site.
3. Contract (actin + myosin) → shrink clot, close wound.
• Analogy: Platelets = patch team pulling duct tape tight.
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Slide 23: Hemostasis
• Definition: stopping bleeding.
• 3 phases: vascular, platelet, coagulation.
• Analogy: Like fixing a leaking pipe step by step.
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Slide 24: Vascular Phase
• Vessel wall contracts (vascular spasm).
• Endothelial cells:
• Expose basement membrane.
• Release endothelins → stimulate contraction/healing.
• Become sticky → platelets attach.
• Analogy: Pinch a hose to slow the leak.
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Slide 25: Platelet Phase
• Platelets stick to exposed collagen.
• Form platelet plug (15 sec after injury).
• Release chemicals: ADP, thromboxane A₂, serotonin, Ca²⁺, PDGF.
• Feedback prevents over-clotting.
• Analogy: Like putting your hand over a hole until repair arrives.
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Slide 26: Coagulation Phase
• Chain reaction of clotting factors.
• Fibrinogen → fibrin (forms net).
• Common pathway:
1. Factor X → prothrombinase.
2. Prothrombin → thrombin.
3. Fibrinogen → fibrin.
• Clot retraction pulls vessel edges together.
• Analogy: Casting a fishing net over the leak.
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Slide 27: Fibrinolysis & Clotting Needs
• Fibrinolysis: clot dissolves after healing.
• t-PA → activates plasminogen → plasmin → digests fibrin.
• Requirements for clotting:
• Calcium (Ca²⁺): needed in all clotting steps.
• Vitamin K: liver makes clotting factors; comes from food + gut bacteria.
• Deficiency = bleeding problems.
• Analogy: Once pipe is repaired, cut away the net (clot)
Updated 6h ago