Bones

Bone serves many important functions. Bones support the body, protect underlying organs, and provide a movable skeleton against which the muscles can work. In addition, bone forms all the cells of the blood, plus takes part in calcium and acid-base balance, and storage of trace elements (such as zinc) needed by cells elsewhere. bone as the most lasting parts of the body, bones are traditionally used for ‘mortal remains’. The longest bone is the femur (thigh bone), which accounts for a quarter of one's stature; the smallest bone is the stapes — one of the tiny ossicles in the middle ear which transmits the vibrations from the ear drum to the inner ear. There are over 200 bones in the adult skeleton. They can be divided into two principal types: the long bones such as the femur, tibia, and humerus, which develop principally from within a cartilaginous framework, and the flat bones such as the skull, bones of the pelvis, and scapula, which develop within membranes of fibrous tissue.

Bone loss

Bone health is measured in two ways. The first is bone density. Bone density defines the thickness of your bone. The second is bone mass. Bone mass means how much bone you have. Bone mass, or the amount of bone you have, usually peaks around age 30. Then bone mass begins to decline. Your body starts to reabsorb bone faster than new bone can be made.
To find bone density, your doctor measures the levels of minerals in your bones. These minerals include:
1. calcium
2. phosphate
3. other minerals
The denser the content of your bone mineral is, the stronger your bones are.
With aging, your body absorbs back calcium and other minerals from your bones. This reabsorption can make your bones weaker and lead to Bone loss. The bones become more vulnerable to fractures and other damage.