Origin is defined as the attachment to what?

• A. A moveable bone
• B. An immovable joint
• C. A tendon
• D. A nerve

Answer: (B)

The main idea is that a muscle has a fixed attachment point (the origin) and a moving attachment point (the insertion). When a muscle contracts, it pulls the insertion toward the origin, causing movement at the joint. The origin is the attachment to the bone that remains relatively stationary during contraction, serving as the anchor for the muscle. That’s why describing the origin as attaching to an immovable (or relatively fixed) end fits best among the options. The other choices point to structures involved with the moving end (the insertion), or to tissues not involved in the attachment, so they don’t describe the origin accurately.