Inside almost every cell in our bodies is a tiny structure called a nucleus. This is the “brain” or “control centre” of the cell. It contains long strands of a very special molecule called DNA DNA is information in the form of a “secret code”. Different sections of the DNA (called genes) code for different parts of what makes you and me unique human beings. Some genes code for the colour of our eyes, or the type of hair we have, or even our hormones and digestive juices.

From bacteria and single-celled algae to fungi, plants and animals - genes determine what living things look like and how they function.