Phospholipid bilayer structure, illustration - stock illustration

Illustration of a phospholipid bilayer structure. Each phospholipid consists of a phosphate group head (blue sphere) and a fatty acid tail (dark orange). In the presence of water the phospholipids spontaneously form a bilayer structure. The tails are hydrophobic and so face inwards, forming an oily core. The hydrophilic heads form the outer layers