1 / 32

Human Anatomy and Physiology

Human Anatomy and Physiology. Blood and hemodynamics. Blood composition. Plasma and formed elements Formed elements Erythrocytes, leukocytes, platelets. Blood composition. Hematocrit <45% anemia (O 2 delivery problems) >45% polycythemia (circulation problem). Plasma. Contents

devi
Télécharger la présentation

Human Anatomy and Physiology

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Human Anatomy and Physiology Blood and hemodynamics

  2. Blood composition • Plasma and formed elements • Formed elements • Erythrocytes, leukocytes, platelets

  3. Blood composition • Hematocrit • <45% anemia (O2 delivery problems) • >45% polycythemia (circulation problem)

  4. Plasma • Contents • 90% water • Protein (albumin acts as a buffer) • Fats, amino acids, salts, gases, enzymes, hormones • Narrow osmolality range

  5. Erythrocytes • Manufactured by erythropoiesis • Committed cell: will form a specific cell type • Erythroblasts undergo rapid mitosis • Reticulocytes enter blood stream (2% of blood)

  6. Erythropoiesis

  7. Erythrocytes • Function: gas exchange Oxy- and deoxyhemoglobin

  8. Erythrocytes • Destruction (3 - 4 months) • Trapped in spleen and destroyed by macrophages • Globin is recycled into amino acids • Iron is used to make new RBC’s • Rest of heme group converted to bilirubin • Bilirubin appears in urine and feces

  9. Erythrocyte disorders • Athlete’s anemia • Thalassemia Sickle-cell anemia Blood doping among athletes

  10. Leukocytes • The only complete cells • Protect against invasion • Move out of blood by diapedesis Move through tissues by amoeboid motion Follow chemical trails by chemotaxis

  11. Leukocytes • Types • Granulocytes: contain cytoplasmic granules • Neutrophils, eosinophils basophils • Agranulocytes: without cytoplasmic granules • Lymphocytes, monocytes • Abundance: Never Let Monkeys Eat Bananas

  12. Neutrophils • Characteristics • Multilobed (3 - 6 lobes) nucleus • Twice the size of RBC’s • Phagocytose bacteria

  13. Eosinophils • Characteristics • Bilobed nucleus • Course granules stain deep red to crimson • Twice the size of RBC’s • Release digestive enzymes to kill worms (too large to be phagocytosed)

  14. Basophils • Characteristics • Course, dark purple, black granules • Twice the size of RBC’s • Release histamine (inflammatory chemical), attract other WBC’s to the area

  15. Lymphocytes • Characteristics • Large, dark purple nucleus • About the size of RBC’s • Act in immune response

  16. Monocytes • Characteristics • Large, dark purple nucleus • Three times the size of RBC’s • Leave blood stream acting to phagocytose viruses and bacteria

  17. Platelets • Megakaryocytes (bone) rupture through sinusoid capillaries • Enucleate, age quickly (10 days) • Hemostasis

  18. Hemostasis • Phases • Vascular spasm • Vasconstriction reduces blood flow • Platelet plug formation • Platelets swell, and adhere to each other • Coagulation • Blood transformed from liquid to a gel

  19. Hemostasis • Phases • Prothrombin activatorformed • Conversion into thrombin • Fibrin seals the hole RBCs and fibrin mesh

  20. Blood typing • RBC plasma membranes bear specific glycoproteins recognized by the body • Glycoproteins called agglutinogens • ABO blood group (A, B, AB or O) • O (common), AB (least common)

  21. Blood typing

  22. Rh blood group • Rh factor: 8 Rh agglutinogens • C, D, E antigens most common • Carrying Rh symbolized by + • Blood groups reported together (i.e., O+)

  23. Rheology • The study of blood flow • Viscosity (i.e., polycythemia)

  24. Rheology • Flow rate = 1/viscosity

  25. Rheology • Flow rate is directly proportional to differences in pressure • F ∞ P1 - P2 or (∆P)

  26. Rheology • Flow rate is indirectly proportional to vessel length (F = 1/L)

  27. Rheology • Flow rate is directly proportional to the fourth power of the radius of the vessel • F ∞ r4

  28. Hemodynamics • Rate of blood flow highest in smallest cross sectional areas • Functional significance Total area Velocity

  29. Blood flow • Laminar flow • Continuous (small vessels) • Pulsatile (large vessels)

  30. Blood flow • Turbulent flow • Definition (obstruction, sharp turns, high flow rate) • Occurs after aortic and pulmonary valves or valves in veins

  31. Compliance • Tendency of blood vessel volume to increase as pressure increases C = ∆V/∆P P1=160 mmHg, P2=120 mmHg, V1=5 l/min. V2=3 l/min. C = 0.05 kPa-1 • Are veins or arteries more compliant ?

  32. Compliance 8X more blood 3X more elasticity 24X more compliant

More Related