Which two bones make up the pectoral girdle?

The pectoral girdle, also known as the shoulder girdle, consists of two main bones that provide support and mobility to the upper limbs. These bones are the clavicle and the scapula. The clavicle, commonly referred to as the collarbone, connects the arm to the body and acts as a strut that holds the shoulder away from the torso. The scapula, or shoulder blade, is a flat, triangular bone that provides attachment points for muscles and serves as the socket for the shoulder joint where the humerus (the upper arm bone) fits in.

The combination of these two bones allows for a wide range of motion in the shoulder, facilitating various movements necessary for upper limb function. The design and placement of the clavicle and scapula not only support the arm's weight but also enable complex arm and shoulder movements needed for daily activities.

In contrast, other options include bones that do not belong to the pectoral girdle. For instance, the humerus is part of the arm, rather than the girdle itself, while the femur and tibia are bones of the lower leg, and the radius is located in the forearm. Therefore, the connection of the clavicle and scapula accurately reflects the structure