Which term describes a muscle action that decreases the angle at a joint (e.g., bending the elbow)?

Which term describes a muscle action that decreases the angle at a joint (e.g., bending the elbow)?

• A. Abduction
• B. External
• C. Flexion
• D. Internal

Answer: (C)

Flexion is the movement that decreases the angle between two bones at a joint. When you bend the elbow, the forearm moves toward the upper arm, reducing the angle at the elbow joint—this is exactly flexion. Abduction involves moving a limb away from the body’s midline, which isn’t about changing the elbow angle. External and internal describe rotation of a limb around its axis, outward or inward, not simply reducing the joint angle. So, the action described is flexion.

Flexion is the movement that decreases the angle between two bones at a joint. When you bend the elbow, the forearm moves toward the upper arm, reducing the angle at the elbow joint—this is exactly flexion. Abduction involves moving a limb away from the body’s midline, which isn’t about changing the elbow angle. External and internal describe rotation of a limb around its axis, outward or inward, not simply reducing the joint angle. So, the action described is flexion.