A muscle that assists the muscle primarily responsible for a given action is a(n) __________.

The major abductor muscle of the upper arm is the __________.

The prime mover for flexion of the thigh is the __________ muscle.

The __________ assists the triceps brachii in forearm extension.

The extensor digitorum muscle is an example of a __________ muscle.

The prime movers of back extension are the __________.

The __________ is the prime mover of dorsiflexion of the foot.

The prime mover of arm extension is the __________.