I believe that glyceraldehyde-3-phosphate (G3P) is a product of the Calvin cycle that is used to form glucose phosphate amino acids or fatty acids.
The Calvin cycle is divided into ; carbon fixation, reduction and regeneration of the starting molecule. Energy from ATP and from the reduced coenzyme NADPH is used to remove a phosphate group from 3PGA and reduce the resulting diphosphoglycerate (DPGA) to produce the 3-carbon sugar glyceraladehyde-3-phosphate (G3P).