This muscle, on the MEDIAL side of the forearm decreases the angle between bones

This shoulder muscle is the prime mover of arm abbduction.

This muscle with two origins is the prime mover of forearm flexion.

This muscle's main action is to extend the forearm at the elbow.

This muscle of forearm flexion inserts on the styloid process of the radius

This muscle runs from the scapula to the mid humerus and functions in adduction and flexion of the arm at the shoulder.

This muscle runs closer to the surface of the body and functions to close the hand into a fist.

The main action of this short muscle is to extend the thumb "thumbs up".