The fluic mosaic model suggests that the cell membrane is composed of a phospholipid bilayer in which a variety of protein is embedded.
Phospholipid is composed of a glycerol molecule, two fatty acid tails, and a phosphate group. The hydrophilic headof a phospholipid molecule is polar and the hydrophobic tail is non-polar because of the presence of C-C and C-H bonds.
The hydrophilic polar heads of the phospholipids face out towards the aqueous environment, while the non-polar fatty acid tails face inwards - hydrophobic. The two layers of phospholipids have a fluid consistency and the proteins that are scattered throughout the membrane have a mosaic quality.