Est-ce que tu vs est-ce que vous

Why do these two sets off words sound different but the only difference is "tu and vous". Est-ce que tu sounds like "Es--ku-che" and the other sounds like "Es-ku-mo-vo'.

NOTE: I tried my best to break down on what it sounds like. It might not be completely accurate but I hope you get the point.

thanks.

"Est-ce que" means literally "Is it that...?" This bit signals a question.
"Tu" is an informal way to address one person whom you know well, or a child. 
"Vous" is used to address someone formally, when first meeting them or at work, or to address two or more people. 

Hope this helps.