Ontology of Biological Attributes entry OBA_2045115 (level of Phosphatidylcholine (O-16:0_20:3) in blood serum) is the amount of a Phosphatidylcholine (O-16:0_20:3) when measured in blood serum. Also known as: blood serum Phosphatidylcholine (O-16:0_20:3) amount.