What is collarbone

How do the bones work?

The mineral content is decisive for the stability of a bone. The most important bone mineral is calcium phosphate. It makes the bones hard and tough. The more minerals a bone contains, the stronger and denser it is. Its stability also depends on the shape and density of the cancellous bone inside.

Two types of living cells are walled into the bone substance that make the bone a kind of permanent construction site: the so-called osteoblasts produce new bone material layer by layer and allow the bone to grow. The osteoclasts do the opposite: they break down older bone substance. Together, these two types of cells ensure that every bone can adapt to its loads and repair itself after a break.

As long as as much material is broken down as it is built up, the bone gradually renews itself without becoming weaker. In this way, the bone substance in the skeleton is completely replaced about every eight years. This remodeling process is controlled by various hormones, for example sex, growth and thyroid hormones.

The skeleton of an adult weighs about seven to nine kilograms. The bone cells make up about one percent of the bone, the rest is the bone substance. It consists of a quarter of water and a quarter of proteins like. Minerals like calcium phosphate make up half of the bone.