Inseion of pectoralis major is at:
High-Yield Explanation
Pectoralis major arises from the anterior surface of the sternal half of the clavicle; from breadth of the half of the anterior surface of the sternum, as low down as the attachment of the cailage of the sixth or seventh rib; from the cailages of all the true ribs, with the exception, frequently, of the first or seventh and from the aponeurosis of the abdominal external oblique muscle. From this extensive origin the fibers converge in a flat tendon, about 5 cm in breadth, which is inseed into the lateral lip of the bicipital groove of the humerus.