Blood Print PDF

10/17/2024 1 2 Functions of Blood...

10/17/2024 1 2 Functions of Blood 1. Transport of gases, nutrients and waste products 2. Transport of processed molecules Blood 3. Transport of regulatory molecules 4. Regulation of pH and osmosis 5. Maintenance of body temperature 6. Protection against foreign substances 7. Clot formation © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 3 4 Composition of Blood 1 Plasma Proteins Plasma: Albumin: 55% of total blood 58% of plasma proteins pale, yellow liquid that surrounds cells helps maintain water balance 91% water, 7% proteins, and 2% other Globulins: 38% of plasma proteins Formed Elements: helps immune system 45% of total blood Fibrinogen: cells and cell fragments 4% of plasma proteins erythrocytes, leukocytes, thrombocytes aids in clot formation © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 5 6 Composition of Blood 2 Hematopoiesis 1 Hematopoiesis is the process that produces formed elements. In the fetus, hematopoiesis occurs in several tissues, including the liver, thymus, spleen, lymph nodes, and red bone marrow. After birth, hematopoiesis is confined primarily to red bone marrow, but some white blood cells are produced in lymphatic tissues. Figure 11.1 © 2019 McGraw-Hill Education ©liquidlibrary/PictureQuest RF © 2019 McGraw-Hill Education 7 8 Hematopoiesis 2 Hematopoiesis 3 All the formed elements of blood are derived from a single population of cells called stem cells, or hemocytoblasts. These stem cells differentiate to give rise to different cell lines, each of which ends with the formation of a particular type of formed element. Figure 11.2 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 9 10 Erythrocytes Hemoglobin 1 Red blood cells (RBC) Main component of erythrocytes Disk-shaped with thick Transports O2 edges Nucleus is lost during Each globin protein is attached to a heme development molecule Live for 120 days Each heme contains one iron atom Function: O2 binds to iron transport O2 to tissues Oxyhemoglobin: Figure 11.3 hemoglobin with an O2 attached © 2019 McGraw-Hill Education (a) ©National Cancer Institute/Science Source © 2019 McGraw-Hill Education 11 12 Hemoglobin 2 Production of Erythrocytes 1. Decreased blood O2 levels cause kidneys to increase production of erythropoietin. 2. Erythropoietin stimulates red bone marrow to produce more erythrocytes. 3. Increased erythrocytes cause an increase in blood O2 levels. Figure 11.4 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 13 Fate of Old Erythrocytes and 14 Red Blood Cell Production Hemoglobin Old red blood cells are removed from blood by macrophages in spleen and liver Hemoglobin is broken down Globin is broken down into amino acids Hemoglobin’s iron is recycled Heme is converted to bilirubin Bilirubin is taken up by liver and released into small intestine as part of bile Figure 11.5 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 15 16 Hemoglobin Breakdown Leukocytes White blood cells (WBC) Lack hemoglobin Larger than erythrocytes Contain a nucleus Functions: fight infections remove dead cells and debris by phagocytosis Figure 11.6 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 17 18 Types of Leukocytes 1 Types of Leukocytes 2 Granulocytes: contain specific granules and 2. Eosinophils: include neutrophils, eosinophils, and basophils reduce inflammation 1. Neutrophils: destroy parasites most common 3. Basophils: remain in blood for 10 to 12 hours then move to least common tissues release histamine and heparin phagocytes © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 19 20 Types of Leukocytes 3 Types of White Blood Cells Agranulocytes: no specific granules 1. Monocytes: largest sized white blood cells produce macrophages 2. Lymphocytes: immune response several different types (T cells and B cells) lead to production of antibodies Figure 11.8 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education (a–e) ©Victor Eroschenko  10/17/2024 21 22 Platelets Blood Loss Platelets are minute fragments of cells, each When blood vessels are damaged, blood can consisting of a small amount of cytoplasm leak into other tissues and disrupt normal surrounded by a cell membrane. function. They are produced in the red bone marrow from Blood that is lost must be replaced by large cells called megakaryocytes. production of new blood or by a transfusion. Small fragments break off from the megakaryocytes and enter the blood as platelets. Platelets play an important role in preventing blood loss. © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 23 24 Preventing Blood Loss Vascular Spasm 1. Vascular spasm: Vascular spasm is an immediate but temporary constriction of a blood vessel that results when temporary constriction of blood vessel smooth muscle within the wall of the vessel 2. Platelet plugs: contracts. can seal up small breaks in blood vessels This constriction can close small vessels completely and stop the flow of blood through them. 3. Blood clotting (coagulation) Vascular spasm is stimulated by chemicals released by cells of the damaged blood vessel wall and by platelets. © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 25 26 Platelet Plug Formation 1 Platelet Plug Formation 2 A platelet plug is very important in maintaining the In platelet aggregation, fibrinogen forms bridges integrity of the damaged blood vessels. between the fibrinogen receptors of numerous The formation of a platelet plug can be described as platelets, resulting in a platelet plug. a series of steps, but in actuality many of these steps occur at the same time. Platelet adhesion occurs first, when platelets stick to the exposed collagen in the damaged blood vessel wall. After platelets adhere to collagen, they become activated, change shape, and release chemicals. © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 27 28 Platelet Plug Formation 3 Blood Clotting Blood can be transformed from a liquid to a gel Clot: network of thread-like proteins called fibrin that trap blood cells and fluid depends on clotting factors Clotting factors: proteins in plasma only activated following injury made in liver Figure 11.9 require vitamin K © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 29 30 Steps in Clot Formation Clot Formation 1. Injury to a blood vessel causes inactive clotting factors to become activated due to exposed conn. tissue or release of thromboplastin 2. Prothrombinase (clotting factor) is formed and acts upon prothrombin 3. Prothrombin is switched to its active form thrombin 4. Thrombin activates fibrinogen into its active form fibrin 5. Fibrin forms a network that traps blood (clots) Figure 11.10 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 31 32 Clot Formation Control Clot Retraction and Fibrinolysis Clots need to be controlled so they don’t spread Clot retraction: throughout the body condensing of clot Anticoagulants: serum in plasma is squeezed out of clot prevent clots from forming helps enhance healing Example - heparin and antithrombin Fibrinolysis: Injury causes enough clotting factors to be process of dissolving clot activated that anticoagulants can’t work in that plasminogen (plasma protein) breaks down clot particular area of the body (fibrin) © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 33 34 Fibrinolysis Blood Grouping Injury or surgery can lead to a blood transfusion Transfusion reactions/Aggulination: clumping of blood cells (bad) Antigens: molecules on surface of erythrocytes Antibodies: proteins in plasma Blood groups: Figure 11.11 named according to antigen (ABO) © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 35 36 ABO Blood Groups 1 ABO Blood Groups 2 In the ABO blood group system, there are two types Antibodies against the antigens are usually of antigens that may appear on the surface of the present in the plasma of blood. red blood cells, type A antigen and type B antigen. Plasma from type A blood contains anti-B Type A blood has type A antigens, type B blood has antibodies, which act against type B antigens; type B antigens, and type AB blood has both types plasma from type B blood contains anti-A of antigens. antibodies, which act against type A antigens. Type O blood has neither A nor B antigens. Type AB blood plasma has neither type of The types of antigens found on the surface of the antibody, and type O blood plasma has both red blood cells are genetically determined. anti-A and anti-B antibodies. © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 37 38 ABO Blood Groups 3 ABO Blood Groups In Caucasians in the United States, the distribution is type O, 47%; type A, 41%; type B, 9%; and type AB, 3%. Among African-Americans, the distribution is type O, 46%; type A, 27%; type B, 20%; and type AB, 7%. Figure 11.12 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 39 Blood Donor and Recipient 40 Agglutination Reaction According to ABO Blood Types O are universal donors because they have no antigens Type A can receive A and O blood Type B can receive B and O blood Type AB can receive A, B, AB blood Type O can only receive O blood Figure 11.13 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 41 42 Rh Blood Group Rh Incompatibility in Pregnancy Rh positive means you have Rh antigens If mother is Rh- and fetus is Rh+ the mother can be exposed to Rh+ blood if fetal blood leaks 95 to 85% of the population is Rh+ through placenta and mixes with mother’s blood. Antibodies only develop if a Rh- person is First time this occurs mother’s blood produces exposed to Rh+ blood by transfusion or from antibodies against antigens. mother to fetus Any repeated mixing of blood causes a reaction. © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 43 44 Hemolytic Disease of Newborn 1 Hemolytic Disease of Newborn 2 This condition occurs when mother produces anti-Rh antibodies that cross placenta and agglutination and hemolysis of fetal erythrocytes occurs can be fatal to fetus prevented if mother is treated with RhoGAM which contains antibodies against Rh antigens Figure 11.14 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 45 46 Diagnostic Blood Tests Hematocrit Complete blood count: provides information such as RBC count, hemoglobin, hematocrit, and WBC count Hematocrit: % of total blood volume composed of RBC Hemoglobin: determines amount of hemoglobin indicate anemia Figure 11.15 © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education 47 48 Diagnostic Blood Tests 2 Diagnostic Blood Tests 3 Prothrombin time: White blood cell differential count: time it takes for blood to begin clotting (9 to 12 sec.) Determines the % of each 5 kinds of leukocytes White blood cell count: neutrophils: 60 to 70% total number of white blood cells lymphocytes: 20 to 25% monocytes: 3 to 8% eosinophils: 2 to 4% basophils: 0.5 to 1% © 2019 McGraw-Hill Education © 2019 McGraw-Hill Education  10/17/2024 49 White Blood Cell Disorders Leukopenia: low white blood cell count caused by radiation, chemotherapy drugs, tumors, viral infections Leukocytosis: high white blood cell count caused by infections and leukemia © 2019 McGraw-Hill Education