Blood A multi-dimensional connective tissue: Vital for transporting materials from the outside world to your cells

I Vant to Teach you BLOOD.. The concentration of water, electrolytes, and blood cell count varies by individual Adults have about 5 liters A hematocrit (HCT) is the percentage of cells, usually about 45%

Blood Components Plasma Red Blood Cells White Blood cells Platelets

Plasma Mostly water Amino acids Proteins Carbohydrates Lipids Vitamins Hormones Electrolytes Cellular wastes

Red Blood Cells: Erythrocytes Bi-concave disks Contain hemoglobin (33% by volume), which turns to oxyhemoglobin when exposed to oxygen They lose their nucleus as they mature Red blood cell counts range from 4.6-6.2 million cells/cubic mm for males, and for adult females 4.2-5.4 million cells/mm3.

Destruction Of Erythrocytes Macrophages (stay tuned) gobble up damaged erythrocytes, mostly takes place in the liver and spleen Hemoglobin breaks down into Heme, (which further breaks down into biliverdin) and Globin, a protein. Heme is recycled, biliverdin breaks down further into bilirubin and ends up in bile, giving it its characteristic color.

Erythrocyte Formation Called hematopoiesis In yolk sac, liver, spleen, but primarily in red marrow in adults Life span: 120 days Erythropoietin controls RBC formation: hormone released by the liver and kidneys Hemocytoblasts are blood stem cells B-complex vitamins help in RBC formation Anemia: Too few RBC’s or hemoglobin on them

White Blood Cells: Leukocytes Granulocytes: granular cytoplasm Neutrophils Eosinophils Basophils Agranulocytes: Not granular Monocytes Lymphocytes

Leukocytes

Granulocytes Twice as large as erythrocytes Develop in red marrow Life span of 12 hours

Granulocytes Neutrophils: Lobed nucleus, fine granules, stain pink, 54-62% of leukocytes in blood Eosinophils: course, uniform granules, stain red, bilobed nucleus, 1-3% of leuk. Basophils: Similar in appearance to eosinophils but they have irregularly shaped granules, stain blue. 1% of Leuk.

Agranulocytes Monocytes: largest blood cells, nuclei vary, 3-9% of leukocytes Lymphocytes: Slightly larger than RBCs, large, round nucleus, 25-33% of circulating leukocytes, live for years

White Blood Cell Counts Number of white blood cells in a cubic millimeter of human blood Usually 5000-10000 cells Leukocytosis: Indicates severe infection, exceeding 10,000 per millimeter Leukopenia: cell count below 5000. Differential White Blood Cell Count: lists relative proportions of white blood cells

Functions of White Blood Cells Neutrophil: Phagocytize small particles Eosinophil: Kills parasites, helps control inflammation and allergic reactions Basophil: Releases heparin and histamine Monocytes: Phagocytizes large particles Lymphocytes: Provides immunity

Platelets Called Thrombocytes Cell fragments Arise form megokaryocytes Half the size of rbc’s Moves by ameboid movement Lives 10 days Platelet count of 130000-360000 per mm3 Close breaks in vessels, clot blood

Plasma Clear, yellowish liquid 92% water Contain: Plasma proteins Albumins Globulins Fibrinogen

Plasma Proteins Most abundant of dissolved chemicals Contain albumins, Globulins and fibrinogen

Albumins 60% of proteins by weight, but smallest in size Made by liver Important in determining Osmotic Pressure of blood Regulates water movement into and out of the blood, and hence blood pressure

Globulins 36% of plasma proteins Alpha, beta, gamma Liver makes alpha and beta globulins, which transport fats and fat soluble vitamins Lymphatic system produces gamma globulins which are a type of antibody

Fibrinogen 4% of plasma proteins Blood coagulation Made in liver Largest of plasma proteins

Nutrients and Gases Amino acids Simple sugars Nucleotides Lipids (triglycerides, phospholipids, cholesterol) Lipoproteins: apoproteins on outer layer can bond with cell receptors

Lipoproteins Apoproteins Less lipids per protein: HDL: delivers leftover chylomicrons which have lost their triglycerides More lipids per protein: LDL: carry cholesterol, delivers to body cells and liver VLDL: transmits liver made triglycerides to body cells Chylomicrons: triglycerides absorbed from intestine, transmits to body tissues. The liver ditches excess cholesterol by excreting it into the liver and as bile salts

More Plasma: Non-proteins Nonprotein nitrogenous substances Urea Amino acids Uric acid Plasma electrolytes: Sodium, potassium, calcium, magnesium, chloride, bicarbonate, phosphate and sulfate ions Gases: Nitrogen Oxygen Carbon Dioxide

Hemostasis Stoppage of bleeding Includes: Blood vessel spasm Platelet plug formation Blood coagulation

Blood Vessel Spasm Vasospasm: Blood vessel smooth muscle contracts, limiting blood escape Platelets release serotonin which causes further smooth muscle contraction

Platelet Plug Formation Platelets stick to any rough surface (like the ragged edge of a broken vessel), and to collagen in connective tissue Platelets also stick together

Blood Coagulation Forms blood clot Many clotting factors get the job done: Some enhance clotting, some inhibit it. Fibrin, tissue thromboplastin, prothrombin activator.