Long bones are hard, dense bones that provide strength,
structure, and mobility. The femur (thigh bone) is a long bone.
A long bone has a shaft and two ends. There are also bones in
the fingers that are classified as "long bones," even though
they are short in length. This is due to the shape of the bones,
not the actual size. Long bones contain yellow bone marrow and
red bone marrow, which produces blood cells.