Early Osmotic History of the Plasma Membrane

Abstract

The following topics, among others, are conisidered: Pfeffer's hypothesis of an invisible plasma membrane, to account for similarities in the osmotic behavior of plant cells and artificial osmometers; early doubts as to the reality of Pfeffer's membrane; denial by colloid chemists of the existence of plasma membranes because of the supposed failure of cells to obey osmotic laws; demonstrations of thin, external cell membranes by electrical and micromanipulative methods; use of the plasma membrane in the mathematical treatment of cell permeability; the nature of so-called "perfect osmometers"; the erythrocyte as an osmometer; hemolytic evidence of the existence of an erythrocyte membrane.