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DO NOT COPY! THIS IS FOR REFERENCE ONLY!!! Receiver Hemostasis Type A, Type A, Type B, Type B, Type AB, Type AB, Type O, Type O, Rh- Rh+ Rh- Rh+ Rh- Rh+ Rh- Rh+  Stoppage of blood flow Type A, Rh- Y Y N N Y Y N N Type A,  Result of a break in a blood vessel Rh+ N Y N N N Y N N Type B,  Hemostasis involves three phases Rh- N N Y Y Y Y N N Type B,  Platelet plug formation Rh+ N N N Y N Y N N

Donor Type  Vascular spasms AB, Rh- N N N N Y Y N N Type  Coagulation AB, Rh+ N N N N N Y N N Type O, Rh- Y Y Y Y Y Y Y Y Type O, Rh+ N Y N Y N Y N Y

Platelets Platelet Plug Formation •(Thrombocytes)  Collagen fibers are exposed by a break in a •Fragments of megakaryocytes in bone blood vessel marrow •Attracted to hemorrhage Platelets respond by becoming “sticky” • Plugs leaks and cling to collagen fibers • Promotes constriction of blood vessel  Anchored platelets release chemicals to • Triggers inflammation attract more platelets • Initiates clotting reaction  Platelets pile up to form a platelet plug http://www.sacs.ucsf.edu/home/cooper/Anat118/BloodCells/blood98/default.htm#Blood- Neutrophils

Vascular Spasms Coagulation

 Anchored platelets release serotonin  Injured tissues release thromboplastin  Thromboplastin, other blood protein clotting factors,  Serotonin causes blood vessel muscles to and calcium ions to form a prothrombin activator spasm (constrict)  Prothrombin activator triggers a clotting cascade  Spasms narrow the blood vessel, decreasing  The amount of prothrombin activator in the blood blood loss is increases proportionally as damage increases

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Clotting Cascade Blood Clotting Fibrin threads:  Prothrombin activator converts prothrombin  The threads stick to damaged tissue, trapping RBCs to thrombin & platelets Prothrombin is a protein always present in  This forms the clot plasma Once a clot begins to form, it promotes additional Thrombin is an enzyme clotting  Thrombin will act upon other clotting factors other  Thrombin catalyzes a reaction in which than fibrinogen, causing more prothrombin to fibrinogen proteins are joined together into form thrombin thread-like fibrin  Positive-feedback mechanism Unstable & short-lived

Blood Clotting Undesirable Clotting

 Fibroblasts will invade the clot and produce fibrous connective tissue, then fix damaged  Thrombus endothelium  A clot in an unbroken blood vessel  This reinforces the clot Coronary thrombosis  Eventually, the clot retracts, releasing serum and drawing the edges of the damaged tissue together Clots in vessels that serve the heart  Plasminogen will be converted to plasmin Cranial thrombosis  The enzyme Plasmin breaks down fibrin and other clot associating proteins Clots in vessels that serve the brain

Undesirable Clotting Undesirable Clotting

 Embolus  Infarction  A clot that breaks away and floats freely in the  When a clot blocks a vessel to the point where blood stream the tissue served by the vessel dies  Keep moving until they reach narrow vessels Myocardial infarction where they may become lodged & block blood flow Heart attack Embolism Clots in vessels that serve the heart Upsets normal heart function

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Bleeding Disorders Developmental Aspects of Blood

 Thrombocytopenia  Sites of blood cell formation  Platelet deficiency  The fetal liver and spleen are early sites of  Even normal movements can cause blood cell formation bleeding from small blood vessels that  Bone marrow takes over hematopoiesis by require platelets for clotting the seventh month  Hemophilia  Fetal hemoglobin differs from  Hereditary bleeding disorder hemoglobin produced after birth  Normal clotting factors are missing

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