Bone #1: Scapula
The scapula has an important role in the body. Its function is to provide an attachment point for the arm, a large span of arm movement, and it forms the shoulder (Tip Sheet #1). The scapula provides an attachment point for the arm (humerus) by being a ball and socket joint. This means the humerus' knob like structure acts as the ball and the scapula acts as the socket. This results in the attachment of the two bones and the formation of the shoulder. Given that the scapula is a socket joint, it enables the arm to make rotary movements, therefore the scapula allows for a large span of arm movement due to its unique structure.
Bone #2: Humerus