AP BIOLOGY

Detailed explanation-1: -This step makes a six-carbon compound that splits into two molecules of a three-carbon compound, 3-phosphoglyceric acid (3-PGA). This reaction is catalyzed by the enzyme RuBP carboxylase/oxygenase, or rubisco.

Detailed explanation-2: -The resulting six-carbon molecule is unstable and immediately splits into two molecules, a phosphorylated three-carbon molecule (3-phosphoglycerate, abbreviated as 3-PGA). The enzyme performing this reaction is called ribulose 1, 5-bisphosphate carboxylase/oxygenase (Rubisco).

Detailed explanation-3: -Six “turns” of the Calvin cycle use chemical energy from ATP to combine six carbon atoms from six CO2 molecules with 12 “hot hydrogens” from NADPH. The result is one molecule of glucose, C6H12O6.

Detailed explanation-4: -An enzyme, RuBisCO, catalyzes the fixation reaction, by combining CO2 with RuBP. The resulting six-carbon compound is broken down into two three-carbon compounds, and the energy in ATP and NADPH is used to convert these molecules into G3P.