BloodWhat is it and why isit important. Chapter 12 Anatomy and Physiology
Blood • How much? • The average adult has about five liters of blood • Men have more than women: • men-1.5 gal women-.875 gal Major function: Deliver essential elements remove harmful wastes absorption and reabsorption of nutrients
Blood percentages • 55 % plasma • Water 90% • proteins 8 % • All other 2%: • Carbohydrates • Lipids • Vitamins and electrolytes • 45 % formed elements • Hematocrit (HCT) level
Blood components • RBC – erythrocytes • have no nuclei once mature (can’t reproduce) • Biconcave discs to transport oxygen (hemoglobin) • Oxyhemaglobin – bright red • Deoxyhemoglobin – maroon/purplish red • Produced by red bone marrow in the ends of spongy bone • Normal count (per 1,000,000 in mm3) for adults: • male 4.6-6.2 female 4.2-5.4
More components of blood • WBC – leukocytes • Develop from hemocytoblasts in response to hormones • 5 types of WBC • Fight off invading particles and infection • Normal count 5,000-10,000 depending upon presence of infection or invader • Plasma • Platelets
Formed elements according to total amount in the blood. • Erythrocytes 99% of the blood • Thrombocytes second most abundant • Leukocytes are the least abundant • but thrombocytes and Leukocytes only make up 1% of the blood.
Types of Blood • 4 Blood Types ( % of US populaiton ) A - 41% B – 9% AB – 3% O – 47% Blood type is determined by the antigen on the blood cells surface. Depending upon the antigen present on the blood cells, the body will produce the opposite antibodies in the blood serum Example: Type A blood, has type A antigens, and anti-B anitbodies in the serum of the blood
Antigens and Antibodies • Antigens are red blood cell surface molecules. • Antibodies are the proteins carried in the plasma. • The interaction of the same antigens and antibodies on a single RBC can cause agglutination, or the clumping of red blood cells.
Blood Types • Blood Types in the U.S. Population • Blood Type A 41% • Blood Type B 9% • Blood Type AB 3% • Blood Type O 47%
Rh Blood Groups • Rh positive blood contains antigen D and also many other Rh antigens. • Rh negative blood lack the Rh antigens. • These antigens determine whether an individual has positive or negative blood type.
Blood Types QuizFill in the chart below 17. What blood type is the universal donor? 18. What blood type is the universal recipient?
Functions of RBCs • Carry oxygen to the cells • The most important chemical in the red blood cell is hemoglobin • Iron forms a weak bond with oxygen to create hemoglobin which transports oxygen to your needed tissues • Life span of 120 days normally
Erythrocyte production (hemopoiesis) • Body is exposed to prolonged oxygen deficiency • Kidneys and liver respond to this by releasing erythropoietin (RBC production hormone) into bloodstream • When blood saturated with erythropoietin reaches red marrow, erythrocyte production is stimulated • This increased RBC production allows bloodstream to transport larger quantities of oxygen in response to the deficiency
Destruction and Recycling of RBC • RBC are flexible and bend as they pass through smaller vessels • Over time these flexible cells become fragile and less efficient, and often damaged • Inefficient or damaged RBC are phagocitized by macrophages by the liver and spleen during circulation • Hemoglobin is broken into: • Heme – iron portion • Globin – protein portion
Recycling RBC • Heme is further decomposed into iron and biliverdin (greenish pigment) • The iron is often transported to hemopoietic tissue in red marrow to be recycled and used in hemopoiesis again • If the iron is not reused it is stored in the liver and iron-protein complex and biliverdin in further converted into orange pigment bilirubin. • Biliverdin and bilirubin is excreted w/bile and digestive bile pigments
Bili-lights for infants with jaundice • **Jaundice – condition affecting infants in which bilirubin accumulates in bloodstream and body stores it in subcutaneous fatty tissue and it causes the skin and corneas to appear yellowish in color • **Caused by the inability of the immature developing liver to handle the decomposition and the digestive system to excrete it • **Infants are placed under UV lights to breakdown the bilirubin and it is excreted with loose bms
Leukocytes White blood cells • The function of white blood cells is to fight off pathogens. Average count (x 1000 cells/mm3) = 5-10 Leukocytosis WBC > 10 Leukopenia WBC < 5 • The two major categories: ( % of present WBC) • granulocytes – neutrophils (54-62%), eosinophils (1-3%), basophils (<1%) • Agranuloctyes – monocytes (3-9%), lymphocytes (25-33%)
Granulocytes • The granulocytes are given different names based on the type of stain the granules in the cytoplasm absorb. • If they absorb an acid stain and appear pink -eosinophils. • If they absorb a basic (alkaline) stain the granules will appear purple - basophils
Granulocytes ( neutrophils) • If neither a strong acid or alkaline stain is absorbed the granules appear somewhat free of stain but usually have a slightly pink or slightly purple appearance. - neutorphils
Granulocytes • Most have irregular, lobed nuclei. • Contain enzymes involved in detoxification of foreign substances, blood clotting,and various immune responses • Neutrophils with one or two lobes are immature or abnormal the presence of these immature leukocytes can indicate a major infection, blood parasites, or a disease such as leukemia.
Granulocytes • The presence of Eosinophils, which are often present in large numbers in the presence of a parasitic infection, have numerous red-or dark pink staining granules. Function in allergic reactions and kill parasites.
Granulocytes continued • Basophils have granules that stain a dark purple almost black. They seem to be all nucleus. These are the rarest of the leukocytes. They function in allergic reactions. • two types of cells that are phagocytes (cell eaters): • neutrophils and monocytes.
Thrombocytes (platelets) • Thrombocytes assist in blood clotting.