Phospholipids are composed of two types of components one is hydrophobic and other is hydrophilic. The fatty acid component is only hydrophobic while rest of the molecules is hydrophilic i.e. glycerol, phosphate, and alcohol attached to phosphate.

Liposomes are closed, solvent filled and self-sealing vesicle which is bound only by a single bilayer and forms a hollow sphere.

Floppases is ATP dependent ABC transporter protein which transports lipids in an opposite direction while flippase is P-type ATPase which transports glycerophospholipid from outer layer to inner membrane.

Scramblase does not require ATP but it is activated by calcium. It moves phospholipids along its concentration gradient, non-specifically in either direction and ensures the monolayer to be equally populated with phospholipids.

FRAP is a technique of fluorescence microscopy which is used to visualize the rapid lateral movement of lipids in the bilayer. The fluidity of lipid bilayer is dependent upon the amount of lipid content and temperature.