only in taxon develops from Gnathostomata <vertebrates> Homo sapiens spleen https://upload.wikimedia.org/wikipedia/commons/d/d6/Illu_spleen.jpg MAT:0000085 MESH:D013154 EMAPA:18767 The organ that functions to filter blood and to store red corpuscles and platelets. uberon BTO:0001281 UBERON:0002106 MA:0000141 galen:Spleen With the advent of clonal selection, the accumulation and segregation of T and B cells in specialized organs for antigen presentation became necessary, and indeed the spleen is found in all jawed vertebrates, but not in agnathans or invertebrates.[well established][VHOG] In humans, it is located in the left upper quadrant of the abdomen. It removes old red blood cells and holds a reserve in case of hemorrhagic shock, especially in animals like horses (not in humans), while recycling iron lien VHOG:0000120 MIAA:0000085 lienal splenic EV:0100055 XAO:0000328 It synthesizes antibodies in its white pulp and removes, from blood and lymph node circulation, antibody-coated bacteria along with antibody-coated blood cells An organ involved in red blood cell filtration and immune response.[AAO] Neither hagfish nor lampreys possess what might be considered a discrete and condensed spleen. Hagfish possess dispersed lymphoid tissue within the submucosa of the intestine (96) associated with the portal vein (97), whereas lymphoid tissue is associated with the typhlosole portion of the intestine in lampreys (96) CALOHA:TS-0956 GAID:1289 EFO:0000869 UMLS:C0037993 NCIT:C12432 TAO:0000436 FMA:7196 AAO:0010395 ZFA:0000436 hemopoietic organ immune organ spleen primordium digestive system element abdominal viscera