• Question: in the DNA structure, there is the double helix, can you explain why only one is useful for the human body system?

    Asked by 798rgah32 to Nicholas on 14 Mar 2017.
    • Photo: Nicholas Younger

      Nicholas Younger answered on 14 Mar 2017:


      So this is a great question, if I understand you right, you’re asking why the only shape the DNA tapes in the human body is the double helix?

      Well firstly, DNA actually can take a number of shapes. They form complex structures called G-Quadruplexes, which is like a double helix, but with 4 strands of DNA, so like a double-double helix. Also when a bit of DNA is being read by the cell’s machinery the double helix gets unwound and pulled apart into 2 strands. Each individual strand can interact with itself to form different shapes, called “hairpins”.

      Although, most of the DNA is a double helix and the reason for this is because this structure is stable, it stays in that shape and keeps the DNA code from changing. If you want to keep accurate DNA information for a long time you need a stable molecule that can’t just change by itself.

      I hope that’s an ok answer, it’s a hard question!