and Production Carried Out by Bone Cells When bones first start
to develop, they start out as cartilage tissue. With time, the
inner part of this cartilage begins to calsify and later,
becomes enveloped in blood vessels by special bone cells called
osteoblasts and osteoclasts. The osteoclast cells' function is
to break down and resorb bone. This they do by secreting special
enzymes. Not remaining idle while the osteoclasts are doing
their job, the osteoblast cells form the bone. As a result of
cooperation between these two groups of cells, the bones develop
and eventually form the entire skeleton. During childhood, when
growth is very rapid, the duty of the osteoblasts is much more
intense. Bone formation needs to be greater than bone resorption
by osteoclasts. Once the skeleton has reached a certain degree
of maturity, however, the formation and resorption processes
begin to balance out. Cells to be found in the bones of every
human being carry out the same duty. They all know how to build
the bone. Aware of