Question

Place the following events of the light-independent reaction in the correct order (1-4):

A. A carbon from CO2 combines with RuBP to form a six-carbon molecule
B. Hydrogens from NADPH are used to form G3P molecules
C. Two molecules of 3-PGAs are formed
D. Two G3P molecules combine to produce glucose

Answer 1

The correct order of events in the light-independent reactions of the Calvin cycle involves the formation of a six-carbon molecule from CO2 and RuBP, the creation of 3-PGAs, the use of hydrogens from NADPH to form G3P, and finally the combination of two G3P molecules to produce glucose.

Step-by-step explanation:

The sequence of events during the light-independent reaction of photosynthesis, particularly in the Calvin cycle, can be listed as follows:

1. A carbon from CO2 combines with RuBP to form a six-carbon molecule. This process is part of the carbon fixation stage.
2. Two molecules of 3-PGAs are formed when the six-carbon molecule splits. This is also part of the carbon fixation stage.
3. Hydrogens from NADPH are used to form G3P molecules. This step is known as the reduction phase where the carbon molecules are reduced using ATP and NADPH to form G3P.
4. Two G3P molecules combine to produce glucose. Although not directly a part of the Calvin cycle, this happens subsequently as two G3Ps leave the cycle to be used in glucose synthesis.