Which of the following best describes the appendicular skeleton?

• A. Bones of the limbs and limb girdles
• B. Bones of the skull
• C. Rib cage bones
• D. Vertebral column bones

Answer: (A)

The appendicular skeleton includes the bones of the limbs and the girdles that attach them to the trunk. This means the bones of the arms and legs, plus the shoulder girdle (clavicle and scapula) and the pelvic girdle (hip bones) that anchor those limbs. In contrast, the axial skeleton comprises the skull, vertebral column, and rib cage. So the best description is that the appendicular skeleton consists of the limbs and their girdles, with examples such as the humerus, radius, ulna, bones of the hands; femur, tibia, fibula, bones of the feet; and the shoulder and hip girdles that connect them to the body. These bones support movement and interaction with the environment.