While in embryonic form, an humans bones are mostly made of cartilage.
As we grow, a process called ossification occurs. This uses calcium to create bone.
Over time, bone eventually become harder and stronger, up to a point.
During old age bones will loose their density and strength. This results in osteoporosis.
During osteoporosis bones are very fragile, and the slightest bump can cause them to break.
We can break bones up into 4 types
Long bones are used for movement, to generate strength and speed.
(Femur)
Short bones are used as shock absorbers, as they help spread the load.
(Tarsal)
Irregular bones provide shape and protection
(Face)
Flat bones protect vital organs and are attached to muscles, to help movement.
(Ribs)
