Answer
Solution for 10.4.16 (solution for 10.4.17 may be found on the page for 10.4.16). Some actions of muscle that insert on the scapula:
1. When one lifts a heavy suitcase, the levator scapulae, and the trapezius ( superior fibers) are
significantly involved in the action.
2,. The pusing of a stalled car involves many muscles, but a shoulder muscle that contributes significantly
to this action is the serratus anterior.
3. The paddling of a canoe ,or a kayak, will combine contributions from trapezius, rhomboid and deltoid
muscles.
Work Step by Step
4. When one tries to square one's shoulders, for example when " standing at attention", the serratus
anterior and the levator scapulae will be involved in the action.
5. In the action of reaching down to pick up a suitcase, the pectoralis minor acts as the prime mover in
depressing the apex of the shoulder.
