What term describes the point of attachment of a muscle that remains relatively stationary during contraction?

• A. Insertion
• B. Origin
• C. Attachment
• D. Pivot

Answer: (B)

When a muscle contracts, the attachment that stays relatively stationary is called the origin. The other end, the insertion, is the part that moves toward the origin as the muscle shortens. This setup lets the muscle pull on the bone or structure it crosses to produce movement. For example, the biceps brachii has its origin on the scapula and its insertion on the radius; during elbow flexion, the radius moves toward the scapula while the origin remains comparatively fixed. The term insertion describes the movable end, while attachment is too vague and pivot isn’t used to describe a muscle’s fixed attachment.