In the human knee-jerk reflex of a seated individual, as the calf is raised from a vertical position to a horizontal position, the muscles of the quadriceps (on the front of the thighs) and the muscles of the hamstring (on the back side of the thighs) are ________.
A) both excited and contracting
B) both inhibited and relaxed
C) excited and inhibited, respectively
D) inhibited and excited, respectively

Question

Quizplus · Accepted Answer

In the knee-jerk reflex, the quadriceps are excited and contract to extend the leg, while the hamstrings are inhibited to allow this movement.

In the Human Knee-Jerk Reflex of a Seated Individual, as the Calf