Which part of the skeletal system includes the skull and vertebrae?

• A. Appendicular
• B. Long bones
• C. Short bones
• D. Axial

Answer: (D)

Think of the skeleton in two main parts: the axial skeleton and the appendicular skeleton. The axial skeleton forms the body's central axis and includes the skull, the vertebral column, and the rib cage. Since the skull and vertebrae sit along this central axis and protect the brain and spinal cord, they belong to the axial skeleton. The appendicular skeleton covers the limbs and their girdles, not the skull or spine. Bone shape categories like long bones and short bones describe form, not region, so they don’t define where the skull and vertebrae belong.