!. Unsportsmanlike Conduct during a play are treated as dead ball fouls, and penalized from the succeeding spot, either on the try, or the kick-off.
2. Holding is a ten yard penalty. Officials refer to something called "the basic spot," and the basic spot on a run play is the end of the run (i.e., here, the end zone). Without getting too deep into it, there are 4 types of penalties. If the penalty on a run play occurs behind the basic spot, the foul is enforced from the spot of the foul, and the down is replayed. If the holding occurred 10 yards beyond the line of scrimmage, the marked off penalty would go to the line of scrimmage, and the down would be repeated. So neither the chains nor the down box would move.