Accelerator Cable or Throttle Body?

[Brice Warnick]

I let my brother-in-law drive my car last week and told him to not be
afraid to tromp the pedal. He did and the engine revved out of control.
I turned the key off and found that the little square black plastic
piece at the end of the accelerator cable had a piece broke off. I was
able to nestle it back under and it has only came off again once. 
I ordered a new cable a few days ago.
Is the little square black plastic piece attached to the end of the
cable or is it part of the throttle body? It appears to be at the end of
the cable but I am not quite sure. I guess I will know for sure when the
cable arrives on Monday.  The cable was only $56.00 from the local
dealer.