OVERVIEW OF BLOOD

Blood Functions – distribution oxygen and nutrients removal of CO2 & wastes hormones – protection prevent blood loss prevent infection – regulation body temp. blood’s temp degrees F normal Ph volume – males ~ 5-6 L – females ~ 4-5 L

Blood Fluid Tissue ~ connective – plasma – blood cells – hematocrit red blood cells 45% Plasma 55% Buffy coat less than 1 % contains white cells and platelets

Composition & Character Plasma – water 90% – protein antibodies albumin fibrogen – electrolytes Na + K + Ca + Cl - Mg + – other components gases – O2 and CO2 glucose fatty acids vitamins

Red Blood Cells Erythrocytes – Transport oxygen to cells – Mature RBC lack a nucleus- eject it – Live 120 days – destroyed by the spleen – Made in red bone marrow – Small biconcave discs thinner in center – Females: million cells/mm3 – Males: million cells/mm3

RBC Hemoglobin – Iron containing pigment – g/100ml – Single cell has about 250 million hemoglobin molecules can bind with 4 oxygens Hematopoiesis- blood cell formation red bone marrow stem cells

RBC Life span – 120 days Anemia – decrease in O2 carrying capacity – Hemoglobin and or RBC deficiency – Symptoms: pale, cold, tired, short of breath – Causes Sickle cellsB12 deficiency HemorrhageLow iron Bacterial infections

Platelets Thrombocytes – Cell fragments – 300,000/mm3 – Hemostasis- stops blood flow “clots” – Platelets cling to damaged site, blood clotting factors and fibrogen form fibrin and then clot – Hemostasis disorders thrombus embolus “clots” hemophilia - no clots

White Blood Cells- Leukocytes – defense and immunity – contain nuclei and organelles – ,000 WBC’s – granular leukocytes neutrophil’s ~ 3, , % of WBC – phagocytes – multilobed nucleus stain pink grains deep purple eosinophils ~ % of WBC – chemicals to kill parasitic worms allergies – red granuals blue-red bilobed nucleus basophils ~ less than 1% of WBC – secrete histamines - vasodilators – chemicals to kill foreign substances – few large blue-purple grains – u or s shaped nucleus

Agranulocytes Monocytes % of WBC – Large cells two to three times larger than RBC – Phagocytes – Present in chronic infections Lymphocytes ~ 1500 – % – small cells - r.b.c size – large dark purple nucleus – Provide immunity B cells and T cells – Secrete antibodies

– WBC count leukocytosis above 11,000 cells / mm 3 – infection leukopenia – low count – drugs steroids flu mumps measles AIDS leukemia – too many immature WBC’s > 17,000 mononucleosis – too many abnormal monocytes

Blood Groups Human Blood Groups – 30 common antigens on RBC’s – Antigens- agglutinogens proteins on cell surfaces – Antibodies- agglutinins proteins made in response to foreign antigens – agglutination “clumping” binding of antibodies to foreign antigens

Blood Groups ABO Systems

Blood Groups RH System – Rh – mother can make antibodies against developing Rh+ fetus – eight different kinds of Rh antigens – most important is antigen D have Rh + – lack antigen D Rh - make Rh antibodies Blood Typing – cross matching