All of us use yeast to ferment glucose. It's kind of why we are all here.
Dextrose is glucose, and sucrose is glucose+fructose. When you ferment sucrose, the yeast first split the molecule into separate glucose and fructose molecules. Maltose, one of the major fermentable sugars in wort, is 2 units of glucose.
Yes, that's true, but anybody tried adding raw glucose in the wort/juice? What is difference in taste, quality of alcohol, proportion of methanol, ethanol and fusel alcohols, etc.