Living Bone - Human Body Part Series

articlemostwanted - Their outer surface may be hard and dry but that doesn't mean your bones aren't alive. Bones are always growing and repairing themselves.

What’s inside our bones?

Bone accounts for one sixth of your body's weight. Its clever structure means it's often lighter than it looks.
Marrow can be found in the spine, skull, and the main leg and arm bones

Spongy bone

Parts of some bones have a honeycomb structure with lots of spaces. This makes them weigh less than if they were solid right through.

Bone marrow

A jellyfish substance called marrow fills the center of many of your larger bones. It supplies your body with red blood cells at a rate of 3 million cells per second.

Compact bone

The hardest and most dense part of the bones is the outer layer. It is made of calcium, a substance we get from our food. Teeth are made of calcium too.
What are the most commonly broken bones?

Broken bone

 

Bones are strong and flexible enough to cope with a lot of pressure, but, as this X-ray shows, they sometimes break. Luckily they can heal themselves. If the broken bone ends hove slipped apart they must be repositioned by a doctor before healing begins.

On the mend

New cells form at each end of the broken bone, closing the gap between them. It takes about 6 weeks for this to happen.

Podded clothes help protect bones from sudden impact.

Looking after your bones

Calcium from milk and cheese is needed to build strong bones. Weight-bearing exercise like walking, climbing, or skating helps to strengthen bones.