Final answer:
3-phosphoglycerate (3PG) is the product of the first phase of the Calvin cycle, and with the help of ATP and NADPH, it is converted into glyceraldehyde 3-phosphate (G3P) during the second phase. The conversion of 3PG to G3P is a reduction reaction where ATP provides energy, and NADPH supplies reducing power.
Step-by-step explanation:
The molecular formula of 3-phosphoglycerate (3PG) and glyceraldehyde 3-phosphate (G3P) are key substances in the Calvin cycle of photosynthesis. 3PG is a three-carbon molecule that is the product of the first phase of the Calvin cycle, where it is produced from the fixation of carbon dioxide. During the second phase of the Calvin cycle, 3PG undergoes reduction reactions using ATP and NADPH produced in the light reactions of photosynthesis and is converted into G3P, a three-carbon sugar phosphate.
Specifically, the reduction of PGA to G3P represents a redox reaction where ATP and NADPH are essential. The ATP provides the necessary energy while NADPH contributes the reducing power, turning 3PG into the higher-energy molecule, G3P, which is used to regenerate the RuBP and synthesizes sugars.
This process not only demonstrates the interplay between different phases of the Calvin cycle but also highlights the importance of energy transfer mechanisms within the cellular metabolism such as the generation of ATP and NADH.