Many people believe that slabs on ground typically should have some reinforcing, but most slabs in North America are unreinforced concrete and perform well. If reinforcing is utilized, the amount that should be used depends on what is to be accomplished.
Micelles are lipid molecules that arrange themselves in a spherical form in aqueous solutions. The formation of a micelle is a response to the amphipathic nature of fatty acids, meaning that they contain both hydrophilic regions (polar head groups) as well as hydrophobic regions (the long hydrophobic chain). Micelles contain polar head groups that usually form the outside as the surface of micelles.
By forming micelles, bile salts break up (or emulsify) large fat particles into smaller ones. The proteins associated with the micelle also attract the digestive enzyme lipase, which breaks down the fats inside the micelle into their component parts for absorption in the gut. Bile is an important player in the digestive system largely because it helps to digest fats. In the gut, fats exist as relatively large globs that cannot be absorbed. To prepare fats for absorption, they must first be broken down into their component parts. An enzyme called lipase (lip-, fat; -ase, break down) is capable of breaking down the large fat globs.