• Question: Why is it that humans need oxygen?

    Asked by courtneyconnor to laurenceharwood on 12 Mar 2012.
    • Photo: Laurence Harwood

      Laurence Harwood answered on 12 Mar 2012:

      We need oxygen to react with the food we eat to generate energy. The technical general term is “metabolism” and it is a bit like controlled burning and, just like a fire needs oxygen, so do our bodies. The energy is used to drive out bodies and also generates heat – that’s why we are warm. The energy is used to make a small molecule called ATP which is the way the body stores energy. When the energy is needed the ATP is converted to ADP, breaking a very reactive chemical bond and giving back the energy