What are the origins and insertions of the Pectoralis major muscle according to the chapter?

The Pectoralis major muscle originates from the clavicle, sternum, and costal cartilages of the second to sixth ribs. It inserts into the greater tubercle of the humerus.

The Pectoralis major muscle has its origins at three main sites: the clavicle, the sternum, and the costal cartilages of the second to sixth ribs. These origins allow the muscle to cover a broad area of the chest. The muscle fibers converge to insert at the greater tubercle of the humerus, which is a prominent area on the upper arm bone. This anatomical arrangement enables the Pectoralis major to perform its functions of flexing, adducting, and medially rotating the shoulder joint.