A readily reversible rise in pH of the medium occurs when unbuffered spinach chloroplasts are illuminated, especially when the initial pH during incubation in the dark is at or below 6.5 (1, 2). This rise in pH had been predicted from an examination of the chemiosmotic mechanisms for phosphorylation detailed by Mitchell (3). It was correlated, in at least a preliminary way, with the existence i...

As the oxygen content of the medium is raised, rat lens respiration increases abruptly to a plateau level at 20 to 30 per cent Ot, and then rises continually through at least 95 per cent Or. Two oxidation reactions may be involved. Oxygen uptake is unexpectedly more active in the acid range than in the alkaline, in a pattern again suggestive of two oxidative mechanisms. The possible identity of...

The rising of bread and the quality of the baked loaf depend upon the nature of the dough and especially upon such of its properties as tenacity, ductility, and elasticity. These properties are hard to define theoretically in this complex colloidal system, but they are, as we have found, related to viscosity or to whatever may determine the resistance of dough to stirring and to flowing through...

The effect of hydrogen-ion concentration on the toxicity of various organic and inorganic compounds has been studied by a number of investigators. In general the results have shown that the toxicity of anions is increased by increasing the hydrogen-ion concentration and that of cations is increased by decreasing the hydrogen-ion concentration, provided the reaction does not affect the solubilit...