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Photophysiology 3, 197.īranton, D., 1969: Membrane structure. 45, 703.īranton, D., 1968: Structure of the photosynthetic apparatus. 55, 1048.īranton, D., 1967: Fracture faces of frozen myelin. Abstracts of Papers 150, 8 c.īranton, D., 1966: Fracture faces of frozen membranes. Singer, 1965: The lipoprotein model for membrane structure. J., 1958: Infrared Spectra of Complex Molecules. Coenwell, 1966: Surface area of human erythrocyte lipids: reinvestigation of experiments on plasma membrane.

Bond, 1968: Comparison of sources of a phosphorylated intermediate in transport ATPase. Crane, 1969: A comparison of chloroplast membrane surfaces visualized by freeze-etch and negative staining techniques and the ultrastructural characterization of membrane fractions obtained from digitonin-treated spinach chloroplasts. This process is experimental and the keywords may be updated as the learning algorithm improves.Īrnold, W., 1933: The effect of ultraviolet light on photosynthesis. These keywords were added by machine and not by the authors. Therefore, early notions about membrane structure were indirectly derived from studies of membrane function, and in fact the chemical composition of the plasma membrane was inferred from its permeability properties before any direct analyses of individual membranes could be attempted. Cell membranes are too thin to be directly visualized in the light microscope, and their boundaries were confused with other structures at the cell surface such as the cytoplasmic cortex in animal cells or the cell wall in plant cells. However, the physical reality of the cell membrane remained controversial for many years. The existence of this membrane was first suggested by de Vries (1885), Pfeffer (1897) and Overton (1899), who demonstrated that plant cells respond osmotically to variations in external osmolarity.

Peripheral proteins are found on the exterior or interior surfaces of membranes, attached either to integral proteins or to phospholipid molecules.The boundary of all cells is delineated by a thin membrane which separates the protoplasm from its environment. Integral proteins may serve as channels or pumps to move materials into or out of the cell. Integral proteins are embedded in the plasma membrane and may span all or part of the membrane. Proteins make up the second major chemical component of plasma membranes. This region has no attraction for water or other polar molecules. In contrast, the interior of the membrane, between its two surfaces, is a hydrophobic or nonpolar region because of the fatty acid tails. Thus, both surfaces of the plasma membrane are hydrophilic. \)) are in contact with aqueous fluid both inside and outside the cell.