The Cardiovascular System

1 The Cardiovascular SystemThe Blood Chapter 19 ...
Author: Harriet Underwood
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1 The Cardiovascular SystemThe Blood Chapter 19

2 Fluids of the Body Cells of the body are serviced by 2 fluids: bloodcomposed of plasma and a variety of cells transports nutrients and wastes interstitial fluid bathes the cells of the body Nutrients and oxygen diffuse from the blood into the interstitial fluid & then into the cells Wastes move in the reverse direction

3 Functions of Blood Transportation RegulationO2, CO2, metabolic wastes, nutrients, heat & hormones Regulation pH through buffers body temperature coolant properties of water vasodilatation of surface vessels dump heat water content of cells by interactions with dissolved ions and proteins Protection from disease & loss of blood

4 Physical Characteristics of BloodDenser and more viscous than water Temperature of 38oC (100.4oF) pH range 8 % of total body weight (20% of extracellular fluid) Blood volume 5 to 6 liters in average male 4 to 5 liters in average female hormonal negative feedback systems maintain constant blood volume and osmotic pressure

5 Components of Blood

6 Plasma Water (~91%) Proteins (~7%) albumins globulins fibrinogenOther Solutes (~1.5%) electrolytes nutrients gases regulatory substances waste products

7 Formed Elements of the Blood

8 Hematocrit Percentage of total blood volume occupied by red blood cells female normal range: % (average of 42%) male normal range: % (average of 47%) Anemia not enough RBCs or not enough hemoglobin Polycythemia too many RBCs (over 65%) Dehydration, blood doping in athletes

9 Hemopoiesis

10 Red Blood Cells O2 / CO2 transportProvides RBCs their ability to carry oxygen No nucleus Biconcave shape

11 RBC Lifecycle and Hemoglobin

12 Control of Erythropoiesis

13 White Blood Cells Characteristics Nucleus lobed round Granulesgranular agranular

14 Lymphocyte Functions: Immune response Direct attack AntibodiesCharacteristics: Agranular Round nucleus Pale blue cytoplasm

15 Monocyte Functions: Phagocytosis Become macrophages Characteristics:Large Agranular U-shaped nucleus

16 Neutrophil Functions: Phagocytize bacteria Characteristics:Nucleus multi-lobed Inconspicuous granules

17 Eosinophil Functions: Kills parasitic wormsDestroys antigen-antibody complexes Characteristics: Nucleus bilobed Red granules

18 Basophil Functions: Release histamine Contain heparin Characteristics:Nucleus lobed Blue-purple granules

19 Emigration of WBCs WBCs roll along endothelium, stick to it & squeeze between cells. adhesion molecules (selectins) help WBCs stick to endothelium displayed near site of injury molecules (integrins) found on neutrophils assist in movement through wall Neutrophils & macrophages phagocytize bacteria & debris chemotaxis of both kinins from injury site & toxins

20 WBC Physiology Less numerous than RBCs5000 to 10,000 cells per drop of blood 1 WBC for every 700 RBC Leukocytosis is a high white blood cell count microbes, strenuous exercise, anesthesia or surgery Leukopenia is low white blood cell count radiation, shock or chemotherapy Only 2% of total WBC population is in circulating blood at any given time rest is in lymphatic fluid, skin, lungs, lymph nodes & spleen

21 Differential WBC CountDetection of changes in numbers of circulating WBCs (percentages of each type) indicates infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction Normal WBC counts neutrophils 60-70% (up if bacterial infection) lymphocyte 20-25% (up if viral infection) monocytes % (up if fungal/viral infection) eosinophil % (up if parasite or allergy reaction) basophil <1% (up if allergy reaction or hypothyroid)

22 Differential WBC Count

23 Complete Blood Count Screens for anemia and infectionTotal RBC, WBC & platelet counts; differential WBC; hematocrit and hemoglobin measurements Normal hemoglobin range infants have 14 to 20 g/100mL of blood adult females have 12 to 16 g/100mL of blood adult males have 13.5 to 18g/100mL of blood

24 Platelets Myeloid stem cells develop eventually into a megakaryocyteSplinters into fragments Each fragment enclosed in a piece of plasma membrane Disc-shaped with many vesicles but no nucleus Help stop blood loss by forming platelet plug Granules contain blood clot promoting chemicals Short life span – 5-9 days

25 Hemostasis - sequence of responses to stop bleeding 1. Vascular spasm2. Platelet plug formation 3. Coagulation (clotting)

26 Summary of Formed Elements

27 Platelet Plug Formation

28 Blood Clotting

29 Clotting Cascade

30 Clotting Factors

31 Blood Groups and Blood Types

32 Blood Groups and Blood Types

33 ABO Blood Group Interactions

34 Rh Factor Rh+ has Rh antigen no Rh antibodyRh- no Rh antigen no Rh antibody exposure of Rh- to Rh+ will produce antibody

36 Blood Typing

37 Anemia - reduced oxygen carrying capacity of the blood.1. Insufficient number of RBCs a. hemorrhagic anemia b. hemolytic anemia c. aplastic anemia 2. Decreased hemoglobin content a. iron-deficiency anemia b. pernicious anemia 3. Abnormal hemoglobin a. thalassemia b. sickle-cell anemia

38 Sickle-Cell Disease (SCD)Genetic defect in hemoglobin molecule (Hb-S) that changes 2 amino acids at very low O2 levels, RBC is deformed by changes in hemoglobin molecule within the RBC sickle-shaped cells rupture easily = causing anemia & clots Person with only one sickle cell gene increased resistance to malaria because RBC membranes leak K+ & lowered levels of K+ kill the parasite infecting the red blood cells

39 Hemophilia Inherited deficiency of clotting factorsbleeding spontaneously or after minor trauma subcutaneous & intramuscular hemorrhaging nosebleeds, blood in urine, articular bleeding & pain Hemophilia A lacks factor VIII (males only) most common Hemophilia B lacks factor IX (males only) Hemophilia C (males & females) less severe because alternate clotting activator exists Treatment is transfusions of fresh plasma or concentrates of the missing clotting factor

40 Leukemia Acute leukemia Chronic leukemiauncontrolled production of immature leukocytes crowding out of normal red bone marrow cells by production of immature WBC prevents production of RBC & platelets Chronic leukemia accumulation of mature WBC in bloodstream because they do not die classified by type of WBC that is predominant---monocytic, lymphocytic