Yes always respect the hierarchy. You are still a lowly student although you are about to be Dr. Somebody and while you feel so special interviewing for your first real doctor job, the resident is still Dr. Above You in So Many Ways. They can get just as prickly about hierarchy as anyone. Also, sometimes the residents tapped to do these interviews are the admin type, or they are looking to be Chief or something one day, so like I said, do not approach them like a peer.