A SEPARATION OF THE REACTIONS IN PHOTOSYNTHESIS BY MEANS OF INTERMITTENT LIGHT

Abstract

Measurements of photosynthesis of Chlorella pyrenoidosa were made in flashing light. By using bright flashes of short duration separated by variable dark periods, the course of the Blackmail reaction after a flash of light was studied under various conditions. The photochemical reaction could take place in about 0.00001 sec. The Blackman reaction required less than 0.04 sec. for completion at 25[degree], and about 0.4 sec. at 11[degree]. Evidence is presented that CO2 enters the process of photosynthesis prior to the Blackman reaction, and that the mechanism involved in the photochemical reaction must undergo the Blackman reaction before it is again free to take part in the photochemical reaction.