Arm Muscles in Action
Diagram of the muscles of the arm in action. Labels: 1, humerus; 2, ulna, 3, biceps muscle; 4, attachment to the humerus; 6, triceps muscle; 7, tendon; 8, a ball to be moved. 9, 10, 11, direction the ulna moves when the biceps muscle contracts. When the triceps muscle contracts, the forearm extends.
GalleriesHuman Muscular System
Cutter, Calvin First Book on Analytic Anatomy, Physiology and Hygiene, Human and Comparative (Philadelphia: J. B. Lippincott & Co., 1875) 38