Phospholipid bilayer membrane
The phospholipid bilayer is composed of 2 layers. Phospholipids form the bilayer and they are constructed from two hydrophobic tails and a hydrophilic head which is polar. These are the most common membrane lipids found in the phospholipid bilayer membrane. This amphiphillic nature of the phospholipids cause them to form a bilayer in water. In water, the hydrophillic heads will dissolve as the charged or uncharged polar heads can form hydrogen bonds or electrostatic interactions. Hydrophobic fatty acid tails will not dissolve in water as thier non polar and cannot form these bonds.