Flexi Says: Phospholipids are a combination of fatty acids, glycerol, and a phosphate group joined together. Phospholipids play a major role in cell membranes. Phospholipid phosphatidylcholine is the major component of lecithin. Lecithin is present in egg yolk and soy beans, among other foods. Lecithin is essential phospholipid in the cells of the body. Lecithin is taken as a medicine for memory disorders.