Final answer:
The axial skeleton forms the central axis of the body and includes the skull, vertebral column, and thoracic cage, primarily protecting vital organs and serving as muscle attachment sites. The appendicular skeleton includes all bones of the limbs and the girdle bones that attach them to the axial skeleton, essential for movement.
Step-by-step explanation:
Differences Between the Axial and Appendicular Skeletons
The human skeleton is categorized into two main parts: the axial skeleton and the appendicular skeleton.
The axial skeleton forms the vertical, central axis of the body and is comprised of bones of the head, neck, chest, and back. This includes the skull, vertebral column (spine, including sacrum and coccyx), and the thoracic cage, which consists of the ribs and sternum.
The axial skeleton serves to protect key organs such as the brain, spinal cord, heart, and lungs, and provides attachment sites for muscles that facilitate movements of the head, neck, and back.
The appendicular skeleton, on the other hand, includes all the bones of the upper and lower limbs, plus the girdle bones that connect the limbs to the axial skeleton.
This division consists of the pectoral and pelvic girdles, limb bones, and the bones of the hands and feet. It features 126 bones and plays a crucial role in facilitating movement by anchoring the limbs to the body's central structure.
The bones of the shoulder region form the pectoral girdle, which anchors the upper limbs to the thoracic cage, while the pelvic girdle attaches the lower limbs to the vertebral column.