In American football, they guard the scrimmage line.
College football kicks off at the 35-yard line.
core of offense line and make calls
There has to be 11 players on offense and Defence for every play. There has to be at least 7 players on the line of scrimmage prior to the snap of the ball. This applies to both offense and defence
As of the 2011 football season they do have the heaviest offensive line in college football.
There have to be at least 7 men on the line of scrimmage for the offense. There are no requirements for the defense.
35 yd line
The ball is placed at the 2 yard line in the NFL and the 3 yard line in college football.
Running back running getting block option by the offense line.
The blue line is the line of scrimmage, or where the offense started the play from. Conversely, the yellow/orange line is where they need to get to for a first down.
Seven on offense. No requirements for the defense