David Samms, age 11, of Fredericton, New Brunswick, Canada, for his question:

HOW MANY BONES ARE IN THE HUMAN BODY?

A bone is a hard substance that forms the framework of the bodies of man and animals with backbones. The separate parts of this framework are called bones, and there are 206 of them in every human body.

More than 650 muscles surround the hones and soft organs of the body. The skeletal muscles pull on the bones and make them move. Tendons are the cords of strong tissue that attach muscles to bones, or to other muscles.

The skeleton has two main parts: the axial skeleton, which includes the bones of the skull, spinal column and ribs, and the appendicular skeleton, which includes the bones of the arms, legs, hips and shoulders.