Question

Explain 'Fluid mosaic model' of plasma membrane.

Answer 1

Fluid mosaic model was proposed by Singer and Nicolson in 1972. According to this model, the quasi-fluid nature of lipids enables lateral movement of proteins within the overall bilayer. This ability to move within the membrane is measured as its fluidity. The plasma membrane is composed of lipids that are arranged in a bilayer and within the membrane with the polar head towards the outer sides and the hydrophilic tails towards the inner part. Because of this the nonpolar tail of saturated hydrocarbons is protected from the aqueous environment. The plasma membrane consists of 52% protein and 40% lipids. Peripheral proteins lie on the surface of membrane while the integral proteins are partially or totally buried in the membrane.