Why do phospholipids form a bilayer in water?

Phospholipids have hydrophobic (water fearing) tails which face each other to form the core of the bilayer while their polar (hydrophilic) head groups face outward.

Explanation: Phospholipids are components of cell membrane. Phospholipids are made up of two parts: the polar (hydrophilic) head group and the nonpolar (hydrophobic) tail. The non polar tails of the Phospholipids are water fearing while the polar head groups are water loving, therefore when phospholipids are mixed with water the hydrophobic tails arrange themselves in a way that they will not come in contact with water molecules. The hydrophobic regions of the lipids face each other forming the interior of the bilayer while the polar head groups face outwards interacting with the surrounding water.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

hammurabi rulers

good lesson