Final answer:
Glycolysis is an ancient, universal metabolic process that evolved very early in the history of life and is conserved across all domains of life.
Step-by-step explanation:
Glycolysis is a series of reactions that extract energy from glucose. This metabolic pathway occurs in the cytoplasm of nearly every cell and is thought to have evolved early in the history of life. Since glycolysis is found across all domains of life and does not require oxygen, we might conclude that it evolved very early in ancestors common to all domains, before the atmosphere contained oxygen, and has been conserved throughout evolution because of its essential role in producing ATP and precursor molecules for cellular metabolism.