BLOOD 19-1 DR. DALIP KUMAR

F UNCTIONS OF B LOOD 1. Transport of: a) Gases, nutrients, waste products b) Processed molecules c) Regulatory molecules 2. Regulation of pH and osmosis 3. Maintenance of body temperature 4. Protection against foreign substances 5. Clot formation 2

C OMPOSITION OF B LOOD 3 BLOOD

P LASMA 1. Liquid part of blood a) Pale yellow made up of 91% water, 9% other 2. Colloid : Liquid containing suspended substances that don’t settle out a) Albumin: Important in regulation of water movement between tissues and blood b) Globulins: Immune system or transport molecules c) Fibrinogen: Responsible for formation of blood clots 4

F ORMED E LEMENTS 1. Red blood cells (erythrocytes) 2. White blood cells (leukocytes) A. Granulocytes a) Neutrophils b) Eosinophils c) Basophils B. Agranulocytes a) Lymphocytes b) Monocytes 3. Platelets (thrombocytes) 5

P RODUCTION OF F ORMED E LEMENTS 1. Hematopoiesis or hemopoiesis: Process of blood cell production 2. Stem cells: All formed elements derived from single population a) Proerythroblasts: Develop into red blood cells b) Myeloblasts: Develop into basophils, neutrophils, eosinophils c) Lymphoblasts: Develop into lymphocytes d) Monoblasts: Develop into monocytes e) Megakaryoblasts: Develop into platelets 6

H EMATOPOIESIS 7

E RYTHROCYTES 1. Structure a) Biconcave, anucleate 2. Components a) Hemoglobin b) Lipids, ATP, carbonic anhydrase 3. Function a) Transport oxygen from lungs to tissues and carbon dioxide from tissues to lungs

H EMOGLOBIN Consists of: 1. 4 globin molecules: Transport carbon dioxide (carbonic anhydrase involved), nitric oxide 2. 4 heme molecules: Transport oxygen 1. Iron is required for oxygen transport 19-9

E RYTHROPOIESIS Production of red blood cells a) Stem cells b) Pro erythroblasts c) early erythroblasts d) Intermediate and late reticulocytes Erythropoietin: Hormone to stimulate RBC production 19-10

H EMOGLOBIN B REAKDOWN 19-11

L EUKOCYTES Protect body against microorganisms and remove dead cells and debris Movements Ameboid Diapedesis Chemotaxis Passive Immunity Active Immunity Antigen – Antibody Types a) Neutrophils : Most common; phagocytic cells destroy bacteria (60%) b) Eosinophils: Detoxify chemicals; reduce inflammation (4%) c) Basophils : Alergic reactions; Release histamine, heparin increase inflam. response (1%) d) Lymphocytes: Immunity 2 types; b & t Cell types. IgG- infection, IgM-microbes, IgA- Resp & GI, IgE- Alergy, IgD- immune response e) Monocytes: Become macrophages

L EUKOCYTES

T HROMBOCYTES Cell fragments pinched off from megakaryocytes in red bone marrow Important in preventing blood loss Platelet plugs Promoting formation and contraction of clots 19-14

B LOOD D ISORDERS Erythrocytosis: RBC overabundance Anemia: Deficiency of hemoglobin Iron-deficiency Pernicious Hemorrhagic Hemolytic Sickle-cell Hemophilia Thrombocytopenia Leukemia Septicemia Malaria Infectious mononucleosis Hepatitis