AP BIOLOGY

Detailed explanation-1: -Extravascular hemolysis Most pathologic hemolysis is extravascular and occurs when damaged or abnormal RBCs are cleared from the circulation by the spleen and liver. The spleen contributes to hemolysis by destroying mildly abnormal RBCs or cells coated with warm antibodies.

Detailed explanation-2: -IgG bound to a RBC can mark the RBC for extravascular destruction, which occurs in the reticuloendothelial system (RES, also known as mononuclear phagocyte system) of primarily the spleen and liver and is effected by macrophages (Fig. 1).

Detailed explanation-3: -Intravascular hemolysis occurs when erythrocytes are destroyed in the blood vessel itself, whereas extravascular hemolysis occurs in the hepatic and splenic macrophages within the reticuloendothelial system.

Detailed explanation-4: -Autoimmune hemolytic anemia and hereditary spherocytosis are examples of extravascular hemolysis because the red blood cells are destroyed in the spleen and other reticuloendothelial tissues.