PowerPoint ® Lecture Slides prepared by Janice Meeking, Mount Royal College C H A P T E R Copyright © 2010 Pearson Education, Inc. 17 Blood

Copyright © 2010 Pearson Education, Inc. Blood - Physical Characteristics and Volume Color varies from scarlet to dark red The pH of blood is 7.35–7.45 Temperature is 38  C Blood accounts for approximately 8% of body weight Average volume: 5–6 L for males, and 4–5 L for females

Copyright © 2010 Pearson Education, Inc. Composition of Blood What type of tissue is blood? It is composed of liquid plasma (matrix) and formed elements Formed elements include: Erythrocytes, or red blood cells (RBCs) Leukocytes, or white blood cells (WBCs) Platelets

Copyright © 2010 Pearson Education, Inc. The hematocrit (also called volume of packed red cells, VPRC, or packed cell volume, PCV) is a measure of the relative percentage of blood cells (mainly erythrocytes) in a given volume of whole blood. Normal hematocrit for Adult Females: 37-48% (ave. 42%) Normal hematocrit for Adult Males: 42-52% (ave. 47%) Hematocrit Measurement

Copyright © 2010 Pearson Education, Inc. Anemia – blood has abnormally low oxygen- carrying capacity It is a symptom rather than a disease itself Blood oxygen levels cannot support normal metabolism Signs/symptoms include fatigue, paleness, shortness of breath, and chills Erythrocyte Disorders

Copyright © 2010 Pearson Education, Inc.  Thalassemias – absent or faulty globin chain in Hb  RBCs are thin, delicate, and deficient in Hb Anemia: Abnormal Hemoglobin

Copyright © 2010 Pearson Education, Inc. Erythrocyte Disorders - polycythemia Polycythemia: excess of RBCs that increase blood viscosity

Copyright © 2010 Pearson Education, Inc. RBC membranes have glycoprotein antigens on their external surfaces These antigens are: Unique to the individual Recognized as foreign if transfused into another individual Promoters of agglutination and are referred to as agglutinogens Presence or absence of these antigens is used to classify blood groups Human Blood Groups

Copyright © 2010 Pearson Education, Inc. The ABO blood groups consists of: Two antigens (A and B) on the surface of the RBCs Two antibodies in the plasma (anti-A and anti-B) ABO blood groups may have various types of antigens and preformed antibodies Agglutinogens and their corresponding antibodies cannot be mixed without serious hemolytic reactions ABO Blood Groups

Copyright © 2010 Pearson Education, Inc. Table 17.4

Copyright © 2010 Pearson Education, Inc. Blood Typing When serum containing anti-A or anti-B agglutinins is added to blood, agglutination will occur between the agglutinin and the corresponding agglutinogens Positive reactions indicate agglutination Blood type being tested RBC agglutinogens Serum Reaction Anti-AAnti-B ABA and B++ BB–+ AA+– ONone––

Copyright © 2010 Pearson Education, Inc. There are eight different Rh agglutinogens, three of which (C, D, and E) are common Presence of the Rh agglutinogens on RBCs is indicated as Rh + Anti-Rh antibodies are not spontaneously formed in Rh – individuals However, if an Rh – individual receives Rh + blood, anti-Rh antibodies form A second exposure to Rh + blood will result in a typical transfusion reaction Rh Blood Groups

Copyright © 2010 Pearson Education, Inc. RH factor blood grouping system A person with Rh- blood can develop Rh antibodies in the blood plasma if he or she receives blood from a person with Rh+ blood, whose Rh antigens can trigger the production of Rh antibodies. A person with Rh+ blood can receive blood from a person with Rh- blood without any problems.

Copyright © 2010 Pearson Education, Inc. Types of WBC Five types of WBC: neutrophils, eosinophils, basophils, monocytes, lymphocytes First 4 are part of the body non-specific defense and lymphocytes are part of the specific defense (will be discussed later in the course) WBC are divided into 2 groups on the basis of their appearance after staining: Granulocytes – visible stained granules Agranulocytes – non-visible granules

Copyright © 2010 Pearson Education, Inc. Granulocytes Granulocytes – Neutrophils – netural granules Eosinophils – acidic staining Basophils – basic staining Contain cytoplasmic granules that stain specifically (acidic, basic, or both) with Wright’s stain Are larger and usually shorter-lived than RBCs Have lobed nuclei Are all phagocytic cells

Copyright © 2010 Pearson Education, Inc. Neutrophils 50-70% of WBC Segmented nuclei with 2-5 lobes (polymorphonuclear) Highly mobile First to arrive to site of injury Attack and digest bacteria that have been marked with antibodies (Ab) Contain peroxidases, hydrolytic enzymes, and defensins (antibiotic-like proteins) Short life span (~10d); if activated live 30min or less Breakdown of a neutrophil releases chemicals that attract other neutrophils

Copyright © 2010 Pearson Education, Inc. Eosinophils account for 1–4% of WBCs Have bilobed nuclei connected via a broad band of nuclear material Have red to crimson (acidophilic) large, granules attack parasites and phagocyte antigen-antibody complexes Eosinophils

Copyright © 2010 Pearson Education, Inc. Account for 0.5% of WBCs Have U- or S-shaped nuclei The staining of the granules is dark and obscure the nucleus Have large, purplish-black (basophilic) granules that contain histamine Histamine – inflammatory chemical that acts as a vasodilator and attracts other WBCs (antihistamines counter this effect) In the site of injury releases granules that contain histamine (vassodilator) and heparin( prevents clotting) Basophils

Copyright © 2010 Pearson Education, Inc. Agranulocytes Agranulocytes: lymphocytes and monocytes Lack visible cytoplasmic granules Have spherical or kidney-shaped nuclei

Copyright © 2010 Pearson Education, Inc. Account for 25% or more of WBCs Have large, dark-purple, circular nuclei with a thin rim of blue cytoplasm Are found mostly in lymphoid tissue (some circulate in the blood) There are two types of lymphocytes: T cells function in the immune response B cells give rise to plasma cells, which produce antibodies Lymphocytes

Copyright © 2010 Pearson Education, Inc. Monocytes Monocytes account for 4–8% of leukocytes They are the largest leukocytes They have abundant pale-blue cytoplasm They have purple-staining, U- or kidney-shaped nuclei They leave the circulation, enter tissue, and differentiate into macrophages

Copyright © 2010 Pearson Education, Inc. Leukocyte Disorders Leukopenia Abnormally low WBC count—drug induced Leukemias Cancerous conditions involving WBCs Named according to the abnormal WBC clone involved Myelocytic leukemia involves myeloblasts Lymphocytic leukemia involves lymphocytes

Copyright © 2010 Pearson Education, Inc. Leukemia Bone marrow totally occupied with cancerous leukocytes Immature nonfunctional WBCs in the bloodstream Death caused by internal hemorrhage and overwhelming infections Treatments include irradiation, antileukemic drugs, and stem cell transplants

Copyright © 2010 Pearson Education, Inc. Platelets Small fragments of megakaryocytes Formation is regulated by thrombopoietin Blue-staining outer region, purple granules Granules contain serotonin, Ca 2+, enzymes, ADP, and platelet-derived growth factor (PDGF)