AFAA Personal Trainer Certification Practice Exam 2025 – All-in-One Guide to Master Your Certification!

The axial skeleton is the part of the skeleton that includes the skull and the vertebral column. It serves a critical function in protecting the central nervous system and providing a foundational structure for the body. The skull encases the brain, safeguarding it from injury, while the vertebral column, or spine, protects the spinal cord and supports the body's posture and flexibility.

In contrast, the appendicular skeleton consists primarily of the limbs and the girdles that attach them to the axial skeleton. Cartilage is a flexible connective tissue found in various parts of the body, including joints, but it does not refer to a specific part of the skeleton that includes the skull and vertebral column. Ligaments are fibrous connective tissues that connect bones to other bones at joints; they play a supportive role but do not make up a part of the skeletal structure by themselves. Therefore, the correct answer highlights the crucial role of the axial skeleton in the overall architecture and protection afforded by the human skeletal system.