They noted that half the calcium required by a mature bone structure must be obtained during those years.

This initial "woven" bone does not have the strong mechanical properties of mature bone.

The growing bones of children can't handle as much stress as the mature bones of adults.

They are mature bone cells.

An osteocyte, a star shaped cell, is the most commonly found cell in mature bone, and can live as long as the organism itself.

In mature bone, osteocytes and their processes reside inside spaces called lacunae and canaliculi, respectively.

Osteoblasts are the immature bone cells, and eventually become entrapped in the bone matrix to become osteocytes- the mature bone cell.

Although the term osteoblast implies an immature cell type, osteoblasts are in fact the mature bone cells entirely responsible for generating bone tissue in animals and humans.

Growth plates, which are made up of soft tissue, are at the tips of maturing bones, and they often aren't strong enough to handle constant pounding or the stress of a repetitive motion.

Biopsies of bone, muscle and other tissue specimens confirmed that the girl had enjoyed good nutrition and had healthy, mature bones, said Dr. Edward McCarthy, a paleopathologist at Johns Hopkins.