Calvin cycle
50 years ago this month
Melvin Calvin was awarded the Nobel prize for Chemistry in 1961 for his work to ellucidate the chemical pathway of the light independent reactions. 
Using Chlorella and radioactive carbon-14 isotope, he exposed the algae to carbon-14 dioxide and then killed and fixed the cells at various times. He then used chromatography to extract the organic molecules that had been made. This allowed him to then analyse the compounds for their structures. His work demonstrated the very short lived 6 carbon structure that breaks into two glycerate-3-phosphates or G-3-P. These were then phosphorylated to form triose phosphates that could further combined to make glucose or regenerate the RuBP to close the cycle.