Photochemical Activity of Chloroplasts Isolated from Etiolated Plants

Abstract

The rates of phosphorylation, ferricyanide, and dye reduction were determined with chloroplasts isolated from Linum usitatissimum grown in darkness and subjected to periods of light of different duration. With an increased period of illumination, the chlorophyll content increased as did also the rate of the three processes measured, but no correlation between these two factors was observed. Neither was there any correlation between the rate of any photochemical reaction and the plastoquinone content. It was concluded that some unspecified factor, possibly structural, which develops during illumination must control the rate of the photochemical reactions.