Which lever system is arranged with the axis or fulcrum in the middle of the force and resistance?

The use of pulley systems in the body decreases the amount of force required for the motion involved.

The longer the lever arm to produce torque, the more force required.

Lable the heart on paper prior to test 😉

This muscle causes a tilt of the scapula, as well as protraction.  

The muscle that inserts on the medial border of the scapula, and originates on the spinous processes of C7-T5 and causes retraction, elevation, and downward rotation is the _____________.

An efferent nerve sends messages via the dorsal horn of the spinal cord to muscles.

Which muscles would be involved in reverse muscle action when using crutches to keep the scapula and rib cage from depressing when looking at the patient posteriorly. 

The shoulder girdle consists of which of the following bones?

Give an example of a force couple in the shoulder girdle. Name the muscles how this action occurs.