The term mosaic is used in arts for an art piece that is composed of many small pieces of materials like stones or glasses. However, in biology it is used for a structure that is made up of different types of cells.
Now if we have to describe a biological mosaic structure , then there is no perfect option than the structure of a cell membrane of animals' cells. Cell membrane is not made up of two types of cell at all but it is a structure that is composed of a lipid bilayer in which proteins are floating as you can see in picture.
The structure was explained as mosaic by fluid mosaic model. If we take a deep look, the double layer of lipids are made up of phospho lipids, which contain two fatty acid tails and a lipid head. The heads are hydrophilic and are outside while tails are hydrophobic and they are inside. This structure has alot of importance as per the function of cell membrane because it maintains the cell's internal environment and separates it from outer environment. This is because
As cell is surrounded by an environment which contain water in excessive amount, therefore nature has made cell membrane in a way that hydrophobic tails do not face water and stay inside the double membrance while hydrophillic heads face the water region outside the cell as well as inside the cell (cytoplasm that contains alot of water content too).
Hope it helps!
