Intro study question

I am studying for my exam this coming up at the end of August and I was wondering if it is really important to know all of the Grand Cru vineyards of France. My main source of studying for this is the introductory workbook and Kevin Zraly's Windows of the World. In her book she lists all of the Premier & Grand Crus  for Reds and Whites. Wasn't sure if I should be focusing on remembering those or really follow the basics of the regions and important villages. Any advice would be great