In muscle actions, which term describes a muscle that opposes or reverses a movement produced by another muscle?

• A. Antagonist
• B. Fixator
• C. Synergist
• D. Agonist (prime mover)

Answer: (A)

Verified step by step guidance

1. Understand the roles of different muscle types during movement: the agonist (prime mover) is the muscle primarily responsible for producing a specific movement.
2. Recognize that the antagonist muscle opposes or reverses the action of the agonist, providing control and balance to the movement.
3. Identify that synergist muscles assist the agonist by adding extra force or reducing unnecessary movement.
4. Know that fixator muscles stabilize the origin of the agonist muscle to allow efficient movement.
5. Conclude that the term describing a muscle that opposes or reverses a movement produced by another muscle is the 'antagonist'.