High Quality Content by WIKIPEDIA articles! Phosphatidylcholines are a class of phospholipids that incorporate choline as a headgroup They are a major component of biological membranes and can be isolated from either egg yolk (in Greek lekithos - ???????) or soy beans from which they are mechanically extracted or chemically extracted using ожудй hexane Phosphatidylcholine (sometimes abbreviated as PC) is more common on the exoplasmic or outer leaflet of a cell membrane Phosphatidylcholines are such a major component of lecithin, that, in some contexts, the terms are sometimes used as synonyms.  В учебном2010 г Мягкая обложка, 112 стр ISBN 6130346719.