The insertion is attached to the:

The insertion is attached to the:

• A. Center part of the muscle
• B. Immovable part of the bone
• C. Movable portion of the bone
• D. Center part of the bone

Answer: (C)

The key idea is understanding how muscles attach to bones to create movement. A muscle has an origin and an insertion. The insertion is the attachment on the bone that moves when the muscle contracts, while the origin sits on the bone that remains relatively fixed. So the insertion is attached to the movable portion of the skeleton. For example, when the biceps contracts, it pulls on the radius at its insertion, moving the forearm toward the shoulder. The origin stays anchored on the scapula or humerus, serving as the fixed point. The center part of the muscle isn’t an attachment site, and the immovable part of the bone describes the origin, not the insertion.

The key idea is understanding how muscles attach to bones to create movement. A muscle has an origin and an insertion. The insertion is the attachment on the bone that moves when the muscle contracts, while the origin sits on the bone that remains relatively fixed. So the insertion is attached to the movable portion of the skeleton. For example, when the biceps contracts, it pulls on the radius at its insertion, moving the forearm toward the shoulder. The origin stays anchored on the scapula or humerus, serving as the fixed point. The center part of the muscle isn’t an attachment site, and the immovable part of the bone describes the origin, not the insertion.