The fluid mosaic model is a model that describes the structure of the plasma membrane of animal cells as a mosaic of components such as phospholipids, proteins, cholesterol, and carbohydrates. The model was first proposed by S.J. Singer and Garth L. Nicolson in 1972 to explain the structure of the plasma membrane/05%3A_Structure_and_Function_of_Plasma_Membranes/5.02%3A_Components_and_Structure_-Fluid_Mosaic_Model). The plasma membrane is a dynamic, flexible structure made up of different components. The main fabric of the membrane is composed of amphiphilic or dual-loving, phospholipid molecules/05%3A_Structure_and_Function_of_Plasma_Membranes/5.02%3A_Components_and_Structure-Fluid_Mosaic_Model). The hydrophilic or water-loving areas of these molecules are in contact with the aqueous fluid both inside and outside the cell, while the hydrophobic, or water-hating molecules, tend to be non-polar/05%3A_Structure_and_Function_of_Plasma_Membranes/5.02%3A_Components_and_Structure-Fluid_Mosaic_Model). The fluid mosaic model describes the structure of the plasma membrane as a mosaic of components that gives the membrane a fluid character/05%3A_Structure_and_Function_of_Plasma_Membranes/5.02%3A_Components_and_Structure-_Fluid_Mosaic_Model). The movement of the mosaic of molecules makes it impossible to form a completely impenetrable barrier. The model explains various characteristics regarding the structure of functional cell membranes, including changes in structure and behavior of cell membranes under different temperatures, as well as the association of membrane proteins with the membranes. The fluidity of the membrane is influenced by temperature, the presence of kinks in the fatty acid tails of the phospholipids, and the presence of cholesterol. The fluid mosaic model is still relevant to understanding the structure, function, and dynamics of biological membranes after more than 40 years.