Warm-Up What are the 4 major components of blood? Give 2 facts about Plasma. Give 2 facts about RBCs.

Leukocytes (WBCs) Part of defense system Protect against bacteria, viruses, parasites Attracted to sites of infection Diapedesis: leave capillary by squeezing between endothelial cells Amoeboid movement Travel toward infection Originate in bone marrow Granulocytes / agranulocytes

White blood cell counts Normally between 4,500-10,000 cells. Leukocytosis – white blood cell count above 10,000. Indicates an infection like appendicitis or leukemia Leukopenia – white blood cell count below 5,000. Can accompany typhoid fever, influenza, measles, mumps, chickenpox, AIDS, or polio.

White blood cell counts Differential WBCC (DIFF) Lists percentages of different leukocytes High neutrophils = bacterial infection High eosinophils = parasitic infection/allergic reaction Low lymphocytes = AIDS

Leukocyte Movement Ameboid – locomotion like an Amoeba Diapedesis – passage through intact vessel walls.

Granulocytes WBCs with granules in cytoplasm Neutrophils Eosinophils Visible with LM Neutrophils Eosinophils Basophils Phagocytic 2xLarger than RBCs Lobed nuclei 12 hour life span

Neutrophils 54-62% of WBCs Lobed nucleus Light staining granules(lt. purple) Digestive enzymes Function Phagocytize & destroy bacteria First cells to respond to infection

http://www.youtube.com/watch?v=I_xh-bkiv_c

Eosinophils 1-3% of WBCs Bilobed nucleus Eosin-staining granules (red) Secrete antihistamine Reduce inflammation Attack parasites Detoxify chemicals

Basophils 0.5% of WBCs Lobed nucleus Large, irregular granules stained deep blue Granules Histamine – creates inflammation in allergic reaction Heparin – prevents blood clotting

Lymphocytes Agranulocyte 25-33% of WBCs Spherical, dark-staining nucleus Thin rim of blue staining cytoplasm Each lymphocyte recognizes and acts against a specific antigen. Used in immunity. May live for years

Lymphocytes T lymphocytes can attack foreign cells directly (17.6)

Lymphocytes B lymphocytes transform into plasma cells and secrete antibodies

Monocytes Agranulocyte 3-9% of WBCs Horseshoe shaped nucleus (round, kidney, oval, & lobed) Grey-blue stained cytoplasm Become wandering macrophages after diapedesis Several weeks to months life span

Platelets (Thrombocytes) Fragments of megakaryocytes in bone marrow Attracted to hemorrhage Plugs leaks Promotes constriction of blood vessel Triggers inflammation Initiates clotting reaction

Platelets Lack a nucleus <half the size of a RBC Amoeboid movement 10 day life span 130,000-360,000 per microliter

Platelets A clot with platelet, fibrin mesh, rbc’s

Hemostasis Stoppage of bleeding Events preventing excessive blood loss Vascular spasm: Vasoconstriction of damaged blood vessels Platelet plug formation Coagulation or blood clotting Serotonin – released by platelets which contracts smooth muscles in the blood vessel walls. Hemostat

Coagulation: Formation of a blood clot Stages Chemicals convert fibrinogen (plasma proteins) into threads of fibrin Stick to damaged blood vessels Meshwork traps blood cells & platelets Clot is formed POSITIVE FEEDBACK

Clot Formation

What is blood? Video Video

Production of Formed Elements Hematopoiesis or hemopoiesis: Process of blood cell production Stem cells: All formed elements derived from single population Proerythroblasts: Develop into red blood cells Myeloblasts: Develop into basophils, neutrophils, eosinophils Lymphoblasts: Develop into lymphocytes Monoblasts: Develop into monocytes Megakaryoblasts: Develop into platelets

The process of blood cell production is called Hematopoiesis Hemorrhage Hematosis Edema

Hematopoiesis Occurs in red marrow Red marrow replaced by yellow in limbs between 8-18 yrs Blood stem cells Pleuripotential Myeloid stem cell Lymphoid stem cells

Hematopoiesis

In an adult, red blood cells are produced in the spleen. red marrow. the liver. yellow marrow.

Blood Grouping Determined by antigens (agglutinogens) on surface of RBCs Antibodies (agglutinins) can bind to RBC antigens, resulting in agglutination (clumping) or hemolysis (rupture) of RBCs Groups ABO and Rh

ABO Blood Groups

Agglutination Reaction

Rh Blood Group First studied in rhesus monkeys Types Rh positive: Have these antigens present on surface of RBCs Rh negative: Do not have these antigens present Hemolytic disease of the newborn (HDN) Mother produces anti-Rh antibodies that cross placenta and cause agglutination and hemolysis of fetal RBCs

Someone that is RH + Does not have antigens present on the RBC surface Have agglutination Have the antigens present on the RBC surface Cause type O blood

blood types must be compatible for transfusions

Sickle cell disease Genetic condition 1 nucleotide substitution 1 amino acid substitution Hbs With low O2 Hbs polymerizes Creates “sickle” shape

Sickle cell disease  flexibility  fragility  blood viscosity  O2  sickling “crisis” Painful ischemia Lack of O2

Blood Disorders Erythrocytosis: RBC overabundance Anemia: Deficiency of hemoglobin Iron-deficiency Pernicious Hemorrhagic Hemolytic Sickle-cell

Blood Disorders Cont Hemophilia - blood doesn’t clot normally. Thrombocytopenia - low blood platelet count Leukemia - a cancer of the blood or bone marrow and is characterized by an abnormal high production of blood cells, usually white blood cells (leukocytes).

Blood Disorders cont. Septicemia - blood poisoning. Malaria – parasites from mosquitoes multiply within RBC’s Infectious mononucleosis – virus that infects B Lymphocytes Hepatitis – virus that cause cell inflammation to occur in organs.

Sickle Cell Anemia can cause Malaria Decrease in Oxygen carrying capacity Increase in Oxygen carrying capacity Hemophilia