The Skeletal System
Overview
Can you imagine what the human body would be like if it were devoid of bones or some other form of supporting framework? Picture a "blob" utilizing amoeboid movement. Ugh! The skeletal system consists of bones and related connective tissues, which include cartilage, tendons, and ligaments. Bone is a living tissue and is functionally dynamic. It provides a supportive framework for vital body organs, serves as areas for muscle attachment, articulates at joints for stability and movement, and assists in respiratory movements. In addition, it provides areas of storage for substances such as calcium and lipids, and blood cell formation occurs within the cavities containing bone marrow.
The skeletal system consists of 206 bones, 80 of which are found in the axial division, and 126 of which make up the appendicular division. Many of the bones of the body, especially those of the appendicular skeleton, provide a system of levers used in movement, and are utilized in numerous ways to control the environment that surrounds you every second of your life. Few people relate the importance of movement as one of the factors necessary for maintaining life, but the body doesn't survive very long without the ability to produce movements.
The study and review for this chapter includes microscopic and macroscopic features of bone, bone development and growth, location and identification of bones, joint classification, and the structure of representa tive articulations.

Review of Learning Outcomes
6-1 Describe the primary functions of the skeletal system.
6-2 Classify bones according to shape, and compare the structures and functions of compact and spongy bone.
6-3 Compare the mechanisms of intramembranous ossification and endochondral ossification.
6-4 Describe the remodeling and homeostatic mechanisms of the skeletal system.
6-5