PGA as the first $\mathrm{CO}_2$ fixation product was discovered in photosynthesis of
PGA as the first $\mathrm{CO}_2$ fixation product was discovered in photosynthesis of
bryophyte
gymnosperm
angiosperm
algae
Solution
The use of radioactive ${ }^{14} \mathrm{C}$ by Melvin Calvin in algal (Chlorella) photosynthesis studies led to the discovery that the first $\mathrm{CO}_2$ fixation product was a 3-carbon organic acid. The first product identified was 3-phosphoglyceric acid (PGA).