Final answer:
Phosphoglucose isomerase is the enzyme that converts glucose-6-phosphate (G6P) to fructose-6-phosphate (F6P) during the second step of glycolysis.
Step-by-step explanation:
The enzyme that converts glucose-6-phosphate (G6P) to fructose-6-phosphate (F6P) is phosphoglucose isomerase.
This enzyme aids in the isomerization process, which is where one molecule is converted into another molecule that has the same chemical composition but a different structure.
It's important to note that this isomerization process takes place during the second step of glycolysis, a critical pathway in cellular respiration.