Bones
Many people believed that the bone is
static and inert, but this idea is
incorrect, the organic and mineral
components of the bone matrix are continually
being recycled and renewed
through a process called remodeling. This process
goes under way throughout
life, as part of normal bone maintenance. Bone
remodeling plays a key factor
between the activities of osteocytes, osteoblasts,
and osteoclasts. In the
adult stage, osteocytes are continually removing and
replacing the
surrounding calcium salts. But osteoclasts and osteoblasts also
remain
active, even after the epiphyseal plates have closed. For the most part
their
activities have a balance. As one osteon forms through the activity
of
osteoblasts, another is destroyed by osteoclasts. In young adult,
approximately
each year one fifth of the adult skeleton is demolished and the
rebuilt or
replaced. The turnover and recycling of minerals give each bone
the ability to
adapt to new stresses. The mechanism that controls the
internal organization and
structure is osteoblast. Whenever a bone is
stressed, the mineral crystals
generate electrical fields. Osteoblasts have
an attraction to these electrical
fields, and once they are in this area they
begin to produce bone. Since bones
are adaptable , their shapes reflect the
forces applied to them. Heavily
streeled bones become thicker and stronget,
whereas bones not being accessible
to ordinary stresses will be deteriorated.
Therefore is important to exercise
daily to maintain a normal bone
structure.