* Formation of micelles; the free fatty acids and the monoglycerides produced by the digestion of lipids form with the bile salts water-soluble complexes called micelles and whose diameter is from 4 to 6 nm.
* Absorption by endocytosis of the micellar contents. The micelles allow the passage in hydrophilic medium of lipophilic substances towards the brush border by endocytosis. The polar fraction of the most soluble molecules is turned outwards and forms, with the bile salts, an "envelope" containing the most insoluble compounds
