Agonist and antagonist relationships

What is a muscle contained entirely within a specific region of interest (such as the hand) called?

A) Intrinsic muscle | B) Extrinsic muscle | C) Antagonist | D) Fixator

Intrinsic muscle

What is a muscle that acts upon a designated region (such as the hand) but arises from another region (such as the forearm) called?

A) Prime mover | B) Synergist | C) Extrinsic muscle | D) Intrinsic muscle

Extrinsic muscle

What is the effect produced by a muscle—whether to produce or prevent a movement—called?

A) Insertion | B) Origin | C) Tone | D) Action

Action

Which functional muscle role produces most of the force during a particular joint action?

A) Antagonist | B) Prime mover (agonist) | C) Fixator | D) Intrinsic muscle

Prime mover (agonist) (e.g., the brachialis during elbow flexion)

Which muscle aids the prime mover by adding power, stabilizing a joint, or modifying the direction of movement?

A) Synergist | B) Antagonist | C) Extrinsic muscle | D) Fixator

Synergist (e.g., the biceps brachii aiding the brachialis during elbow flexion)

Which muscle opposes the prime mover and often maintains tension to limit its speed or range, preventing joint injury?

A) Fixator | B) Synergist | C) Antagonist | D) Prime mover

Antagonist

Why do joints require antagonistic pairs of muscles (such as the brachialis and triceps brachii)?

A) Because agonists fatigue after one second | B) Because muscles can only pull | C) Because joints can only move in one direction | D) Because antagonists hold bones to the axial skeleton

Because muscles can only pull

During elbow extension, which muscle acts as the prime mover and which acts as the antagonist?

A) Brachialis is prime mover; biceps brachii is antagonist | B) Biceps brachii is prime mover; brachialis is antagonist | C) Rhomboids are prime mover; triceps brachii is antagonist | D) Triceps brachii is prime mover; brachialis is antagonist

Triceps brachii is prime mover; brachialis is antagonist

Which type of muscle prevents a bone from moving, holding it steady so another muscle attached to it can pull on something else?

A) Fixator | B) Antagonist | C) Intrinsic muscle | D) Prime mover

Fixator

When the biceps brachii flexes the elbow, which muscles act as fixators to hold the scapula firmly in place against the vertebral column?

A) Gastrocnemius | B) Triceps brachii | C) Rhomboids | D) Quadriceps

Rhomboids