What Is the Skeleton?

The exquisite appearance of the human body is founded upon our skeleton. Our skeleton is a combination of 206 separate bones and supporting ligaments and cartilage. The bones of our skeleton are attached to muscles, which allow us to move about. Bones also provide protection. For instance, the skull and the vertebrae enclose the brain and spinal cord, respectively, thereby protecting the invaluable central nervous system (CNS). Twelve pairs of ribs extend from our vertebrae and protect the organs of our chest. Bone also serves as a storage site for several minerals, such as calcium and phosphorus, and is the site of formation for many of our blood cells.
 

By approximately 6 weeks of pregnancy the skeleton is rapidly developing and is visible in a sonogram. Bones continue to grow until early adulthood, complementing the growth of other body tissue. Up until this point, bones grow in both length and diameter. Around this time the longer bones of our body, such as the femur, humerus, tibia, and fibula, begin to lose the ability to grow lengthwise and our adult height is realized. Some of the bones of the lower jaw and nose continue to grow throughout our lives, although the rate of growth slows dramatically. As you may expect, the longest, heaviest, and strongest bone in our body is the femur or thigh bone. These bones extend nearly two feet in some of us, and provide much of the support we need against the force of gravity. Meanwhile, the three small bones in the inner ear are the smallest bones in our body. In addition, the tiny pisiform bone of the wrist is also very small, having the approximate size of a pea.