anatomical entity blood serum BTO:0000133 BTO:0001239 CALOHA:TS-0923 EHDAA2:0004728 EMAPA:35770 FMA:63083 MA:0002502 NCIT:C13325 The portion of blood plasma that excludes clotting factors. UBERON:0001977 UMLS:C0229671 serum uberon