Techniques in studies of photosynthesis

The use of both stable and radioactive isotopes has led to major advances in the understanding of the basic mechanisms of photosynthesis. An early use of isotopic material in photosynthetic investigations was the demonstration using 18O, that O2 evolved in photosynthesis was derived from water rather than from CO2. When the long-lived isotope of carbon, 14C, became available in 1945, its use, coupled with two-dimensional chromatography developed a few years earlier, enabled Calvin and Benson (1948) to devise experiments to elucidate the pathway of photosynthetic 14CO2 fixation, 12 refs, 6 figs, 10 tabs