Final answer:
Two molecules of ATP are required during the priming stage of glycolysis to transfer phosphates and prime glucose, as ATP acts as the phosphate donor.
Step-by-step explanation:
During the priming stage of glycolysis, two reactions involve the transfer of phosphates to prime glucose, and thus two molecules of ATP (adenosine triphosphate) are required to supply the phosphates.
The priming phase of glycolysis starts with the phosphorylation of glucose by hexokinase to form glucose-6-phosphate using one ATP. Subsequently, under the action of phosphofructokinase, glucose-6-phosphate is converted into fructose-6-phosphate, which also requires an ATP molecule to be converted into fructose-1,6-bisphosphate. These steps consume two ATP molecules, which are the source of the phosphates added to the glucose molecule.
In summary, ATP is the molecule that donates phosphates during the priming phase of glycolysis, and two molecules of ATP are used per glucose molecule that enters the pathway.