2. BLOOD CHAPTER 10 Pg 290 Composition: liquid tissue -8% body weight -5-6 L in adult 1) Solid: 45% of blood -living cells: formed elements 1. Erythrocytes~45% 2. Leukocytes~1% 3. Platelets~1% 2) Liquid – 55% -nonliving—plasma Color: scarlet with oxygen dull red low oxygen pH: 7.3-7.4

3. Function pg 295 Transport:1. Nutrients 2. Excretory products 3. Gases 4. Hormones 5. Cells 6. Heat 7. Coagulation 8. Maintenance of ions, pH

4. Hematopoiesis pg 295 Production of blood cells Place—Red bone marrow Ex: Formation: 1. Hemocytoblast (stem cell) 2. Lymphoid stem OR Myeloid stem 3. Lymphocytes All other blood cells R.B.C.– life span 100-120 days -production controlled by : Erythropoietin

5. Lymphocytes: production controlled by CSF—colony stimulating factor triggered by bacteria Plasma pg 290-295 -90% water -10% plasma proteins & salts Function of plasma proteins: blood clotting, osmotic balance, antibodies, pH Function of formed elements 1. Erythrocytes RBC: -function: carry O 2 & CO 2 -anucleated -hemoglobin -lack mitochondria -5 million RBC/ mm 3

6. Red blood cells

7. 2. Leukocytes WBC -function: immune -4,000  11,000/mm 3 -increase number during infection Leukocytosis increases WBC count

8. W.B.C. : 2 Groups 1. Granulocytes- granular & lobed nuclei 3 types 1) Neutrophils—phagocytes 2) Eosinophils—allergies 3) Basophils—histamine 2. Agranulocytes- no granulars & normal nucleus 2 types 1) Lymphocytes—immune T-cells B-cells 2) Monocytes--macrophage Eosinophils Neutrophils

10. Platelets : fragments of megakaryocyte function: blood clotting -300,000/mm 3 Hemostasis: blood clotting coagulation 2-6 minutes 1. Platelets become sticky –white thrombus 2. Release seratonin –constricts blood vessels 3. Release chemicals form fibrin proteins makes a mesh Blood without clotting proteins –serum helps clotting—high temperatures, rough surface hinders clotting—low calcium, low vitamin K

11. Platelets forming a mesh