What is the specific function of the structure labeled f? basic motor reflex pathways. what is the specific function of the structure labeled f? basic motor reflex pathways. determination of muscle tension increasing tension of the surrounding muscle increasing tension of the antagonistic muscle determination of muscle length?

The function of the part labelled F on the attached diagram is increasing tension of the antagonistic muscle.  A sudden stretch in a muscle leads to the contraction of the stretched muscle (E) and the relaxation of the antagonistic muscle (G). Antagonist and agonist muscles occur in pairs, for example the biceps and triceps; to contract the triceps relaxes while the biceps contracts to lift the arm.