Inverse micelle. Cut-away illustration of phospholipids forming an inverse, or reverse, micelle. Each phospholipid molecule consists of a hydrophilic (water-soluble) phosphate group head (round) and a hydrophobic (water-insoluble) fatty acid tail. In non-polar solvents the phospholipids form spherical aggregates known as micelles with the heads pointed inwards and the tails outwards. This is the inverse of the position the phospholipids take in polar solvents such as water.