The skeletal system provides structural rigidity, protects internal organs, and serves as the main storage for calcium.

The primary functions of the skeleton are to provide a rigid internal structure that can support the weight of the body against the force of gravity, and to provide a structure upon which muscles can act to produce movements of the body. The lower portion of the skeleton is specialized for stability during walking or running. In contrast, the upper skeleton has greater mobility and ranges of motion, features that allow you to lift and carry objects or turn your head and trunk.

In addition to providing for support and movements of the body, the skeleton has protective functions. It protects the internal organs, including the brain, spinal cord, heart, lungs, and pelvic organs.

Consequently, the skeletal system serves as the main storage system for calcium and phosphorus. The importance of this storage is to help regulate mineral balance in the bloodstream. When the fluctuation of minerals is high, these minerals are stored in bone; when it is low, minerals are withdrawn from the bone.

Key Points

• The primary functions of the skeleton are to provide a rigid internal structure that can support the weight of the body against the force of gravity, and to provide a structure upon which muscles can act to produce movements of the body.

• The skeleton has protective functions that guard the internal organs, including the brain, spinal cord, heart, lungs, and pelvic organs.

• The skeletal system serves as the main storage system for calcium and phosphorus.

Key Terms

skeleton: a body part that forms the supporting structure of an organism

internal organs: any organs found inside the body