Final answer:
Membranes form spontaneously through the interaction of phospholipids in an aqueous environment, resulting in the formation of micelles.
Step-by-step explanation:
Membranes form spontaneously through the interaction of phospholipids in an aqueous environment. These phospholipids aggregate to exclude their hydrophobic fatty tails from water, forming micelles. Micelles are spherical vesicles that self-assemble due to the natural aggregation of the hydrophobic fatty acid domains of these amphipathic molecules.