• Question: What are bones made out of?

    Asked by jabber8 to Aime, Akshat, Diana, Gemma, Judith on 23 Jun 2011.
    • Photo: Judith McCann

      Judith McCann answered on 21 Jun 2011:

      Bones are made out of collagen fibres with a ceramic called hydroxy apaptite(HA) surrounding them, they contain blood vessels and three kinds of cells, osetoblast, osteocytes and osteoclasts. One breaks down ceramic HA by making acid, one creates new HA and the other detects pressure.

      This is done so if you use your bones more (put them under more pressure) they grow to be denser, which is one fo teh reasons that bones get weaker with age (if your using them less they loose density!)

    • Photo: Gemma Sharp

      Gemma Sharp answered on 21 Jun 2011:

      Bones have to be strong, but they also have to be lightweight, so they have a light, honeycomb-like core made from bone tissue (or osseous tissue if you want to be really scientific about it).

      Bones also contain cartilage, bone marrow (a flexible tissue that makes new blood cells), nerves, blood vessels, and two layers of connective tissue on the outside of bones called the endosteum and the periosteum.

      Thanks for the question, it’s a good un 🙂

    • Photo: Akshat Rathi

      Akshat Rathi answered on 23 Jun 2011:

      Nice answers both of them.

      I’ll elaborate what Gemma meant by a honeycomb structure. It looks something like this http://tomastomas108.wordpress.com/page/14/ when seen through a microscope. The structure allows for a lot of empty space and yet because of what the bone is made out of this structure is very strong. Strong enough to take an immense amount of load. So much so that the world record for lifting heavy weights is well over 400 kg (approximately 10 school students!!).

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