Explain the Skeletal System?

Skeletal System: The support framework, or skeleton, in the human body is composed of mostly hard mineral substances. Unlike crustaceans or insects who possess external skeletons (exoskeletons), humans have internal skeletons, or endoskeletons.

The human skeleton is divided into two parts, the axial skeleton and the appendicular skeleton. The axial skeleton includes the spine; the ribs; the sacrum, five united vertebrae at the end of the spinal column; the sternum or breastbone; and the cranium, or braincase. The appendicular skeleton contains 126 bones, including those of the arms, legs (the appendages), pelvis, and shoulders.

In addition functioning in locomotion, bones serve as mineral storage reservoirs and as protective cages -- the cranium protects the delicate brain tissue, ribs protect lungs, heart and other internal organs, and the backbone protects the spinal cord.