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Q.
Algae used by Calvin and associates for photosynthetic research is
NTA AbhyasNTA Abhyas 2020Photosynthesis in Higher Plants
Solution:
Melvin Calvin used radioactive 14C in algae to study photosynthesis and his studies led to the discovery that the first CO2 fixation product was a 3-carbon organic acid. He also contributed to working out the complete biosynthetic pathway and hence it was called the Calvin cycle. Calvin used isotopes $^{14}C$ in chlorella for knowing the carbon path in photosynthesis.