Final answer:
In the energy investment phase of glycolysis, glucose combined with 2 ATPs produces two molecules of glyceraldehyde 3-phosphate (G3P).
Step-by-step explanation:
During the energy investment phase of glycolysis, glucose is combined with 2 ATP molecules to facilitate the phosphorylation of glucose. This reaction produces two molecules of glyceraldehyde 3-phosphate (G3P), which then enter the energy payoff phase.
As described in the Embden-Meyerhof-Parnas glycolysis pathway, this phase consumes a total of 2 ATPs to modify the glucose molecule, which is then cleaved into two G3P molecules that will continue through glycolysis to eventually produce a net gain of energy in the form of ATP and reduced coenzymes.