[Dynamics of the cell membranes].

The Author, after recalling the fundamental concepts of the function and structure of living cells, illustrate the functions characteristic of cellular membranes. He examines in detail the principal models which have been proposed for the interpretation of the structure of membranes, particularly those of DANIELLI and DAVSON and of ROBERTSON. He recalls his own biochemical experiments on the endoplasmic reticulum of the liver and spleen, from which useful information can be drawn on the locating of some catalytic proteins in the membrane. He then devoted particular attention to the relationships between proteins, lipids and glucides as constitutent parts of membranes and discusses the recent "fluid mosaic model" proposed by SINGER and NICOLSON. He concludes giving some examples of the functional flexibility of membranes and remarks that the collaboration between biochemists and electron microscopists has proved in the last few years to be a fertile point of encounter, promising results which will provide spectacular information on the structure and function of cellular membranes.