Yes. If you've ever played Alpha Protocol, it works the same way. You don't get to choose exactly what your character says - you choose his attitude, which determines what happens next in the conversation.

Sometimes you'll get a unique option based on your class, which usually unlocks benefits you wouldn't have obtained through the normal dialogue options.

EDIT: I forgot to mention that certain NPCs and companions will treat you differently depending on your responses. For example, Gaius likes Serious responses and dislikes Snide ones.