Which category of skeletal muscles are primarily involved in facial expressions?

• A. Axial muscles
• B. Appendicular muscles
• C. Cardiac muscles
• D. Smooth muscles

Answer: (A)

Axial muscles are involved in facial expressions. These skeletal muscles are located in the head, neck, and trunk region and attach to skin rather than to bones of the limbs, allowing the face to move the skin to convey emotions (smiling, frowning, raising the eyebrows, etc.). They are under voluntary control and are not the smooth muscles that line internal organs or blood vessels, nor the cardiac muscle of the heart. Appendicular muscles, by contrast, move the limbs and their girdles, which is why they aren’t responsible for facial expressions.