BLOOD

Functions of Blood Transportation Regulation Protection oxygen and carbon dioxide nutrients, hormones, metabolic wastes heat Regulation pH through buffer systems body temperature osmotic pressure within cells Protection clot blood Fight disease

Components of Blood Plasma = straw colored liquid portion Water = 92% Solutes – electrolytes, hormones, gases, etc. = 8% Formed Elements = Blood Cells Erythrocytes Leukocytes Thrombocytes

Plasma and Serum Plasmapheresis: separates plasma from blood cells Serum --when blood clotting factors are removed

Hematopoiesis Production of blood cells occurs in red bone marrow From stem cells called Hemocytoblasts Erythropoietin produced in the kidneys starts new RBCs (see pg 372)

Erythrocytes (RBC’s) Carry Hemoglobin --gives whole blood it’s red color Have no nucleus Live about 120 days

Hemoglobin Heme = iron – contains 4 per globin –gives blood it’s color Globin = protein ( carries some CO2)

Leukocytes (WBC’s) main function protection from foreign particles Two Main Types: Granulocytes Agranulocytes

Granulocytes Neutrophils Eosinophils Basophils Phagocytes – most numerous Eosinophils Removes allergens, reduces inflammation, increase with virus Basophils promotes inflammation by secreting histamines Heparin to prevent blood clotting

Agranulocytes Lymphocytes Monocytes produce antibodies T and B cells) become Macrophages Large “large eaters”

Thrombocytes (Platelets) Clot blood (hemostasis) and repair damaged blood vessels life span of about 5 to 9 days

Hemostasis mechanism by which bleeding is stopped Three Basic Mechanisms Vascular Spasms Platelet Plug Formation Coagulation (Clotting)

Vascular Spasm contraction of the smooth muscles in the vascular walls of a damaged blood vessel reflexes from pain receptors

Platelet Plug Formation Platelet Adhesion = platelets contact and stick to walls of damaged vessels Platelet Release Reaction = platelets extend projections and release content of their granules Platelet Aggregation = platelets gather in area of wound or injury forms a Platelet Plug to stop bleeding

Coagulation (Clotting) Several steps needed for process to work Intrinsic (within blood) Extrinsic (within tissues) forms a Clot = a network of fibrinogen(protein fibers) changes to fibrin

Coagulation Fibrinogen changed to fibrin

Thrombus and Embolus Thrombus: stationary clot Embolus: traveling clot – effects 4 organs – heart, lungs, brain and kidneys Clot may be blood, gas, fat, wastes, etc.

ABO Blood Typing each parent contributes antigens (agglutinogens), or lack of antigens to their offspring O + O = O blood type A + O and A + A = A blood type B + O and B + B = B blood type A + B = AB blood type

Rh Factor Presence or absence of Protein D on erythrocyte May effect – mother’s 2nd pregnancy May cause Hemolytic disease of the newborn.

THE END OF BLOOD

bicuspid

bicuspid