It contains fifty three millimetres of DNA, weighs a hundred and sixty nine quadrillionths of a gram and has even helped in the work towards a cure for cancer.
David Bainbridge, author of a new book The X in Sex joins Jenni to tell her about the book. 'The X in Sex: How the X Chromosome Controls our Lives' by David Bainbridge published by Harvard University Press £15.50; ISBN: 0674010280.
