Pectoralis Major

Origin:  Medial half of the clavicle, sternum, upper costal cartilages (1-7) and the aponeurosis of the external oblique.

Insertion:  Lateral lip of the intertubercular  groove of the humerus,  crest of the greater tubercle of the humerus

Actions: Flex, extend, adduct and medially rotate  the arm at the shoulder.

 [embedyt]http://www.youtube.com/watch?v=H7myZ2eoSDU[/embedyt]