But once this step takes place, we call it the committed step because it commits that sugar to undergo that process of glycolysis. So in step three of stage one, phosphor fructokinase PFK adds a second phosphoryl group onto that sugar to make it much less stable, higher in energy and therefore much more reactive. And that will allow it to actually break down in stage two into smaller components as we'll see in the next lecture. And so we transform the fructose six phosphate into fructose one six bisphosphate. And this is what we call the commitment step. It commits it to the process of glycolysis.