Light-enhanced potassium absorption by corn leaf tissue.

The rate of absorption of potassium by slices of corn leaf in the light was about twice the rate in the dark. When the light was turned on or off, changes in the rate of absorption took place some minutes after the change in illumination. Experiments with the antimetabolites, 2,4-dinitrophenol and cyanide, indicated that the source of energy for active accumulation of potassium by green tissue in the light was different from that in the dark. In the light, energy was closely linked to photosynthetic reactions; in the dark, it was linked to respiratory processes.