EFFECTS OF VARIOUS AGENTS ON THE STRUCTURAL VISCOSITY OF ELODEA PROTOPLASM

Abstract

The centrifuge method was used to determine the effects of various agents on protoplasmic viscosity in cells of Elodea. Concs, of 2% ethylene chlorhydrin, 3% thiourea, 4% ether, 6% ethyl alcohol, 3.5% propyl alcohol, 1.5% butyl alcohol, 0.0001 M cupric chloride, or 0.001 M ZnSO4 conditioned decreases in the structural viscosity when the exposures were 2 hrs. or less. Decreases in viscosity were presumed to result from dissociations (that is, the splitting of long molecules into units of smaller size) of protoplasmic proteins. Concs. 1/2-1/4 of those above also decreased the viscosity; with concs, greater than those mentioned, an initial decrease in viscosity was usually followed by an increase. Plasmolysis with 0.6 [image] sucrose or 0.3 [image] KC1 conditioned a decrease in viscosity. The protoplasmic viscosity was lower at a temp. of 3[degree] C than it was at 21[degree] C. It is suggested that the dissociation of protoplasmic proteins conditions increased rates of respiration, polysaccharide hydrolysis, and imbibition and that the dissociation may be primarily responsible for the breaking of rest periods.