Now, glycolysis is an anaerobic process and that means it does not require oxygen to actually take place. And that's why glycolysis is used by all different types of cells, including prokaryotic and eukaryotic cells. Now, glycolysis can be divided into three stages. We have stage one, stage Two and stage three. Now, in stage one, we actually use energy. So the entire purpose of stage one is to prepare the glucose molecule for a breakdown.