Cell. Part 2, The chemistry of life.

The second in a three-part series in which biologist Adam Rutherford looks in depth at cells. In this part he shows how scientists tried to understand the chemistry making up cell life. In Germany, Friedrich Miescher began to study white blood cells in order to discover the chemistry of the nucleus; he discovered an unusual molecule which we now know as DNA. The discovery of cell division and naming of chromosomes was discovered by Theodor Boveri; his work with sea urchins is shown in detail and is thought to herald later work in genetics. Thomas Hunt Morgan studied the fruit fly in order to understand heredity; he coined the term gene but still it was not known what a gene was made from. Fred Griffith was researching the bacteria that caused pneumonia; Oswald Avery, across the globe, discovered the molecule that genes are made of and this showed that DNA was actually controlling cells. It was now crucial to know what DNA was and what it was for. Maurice Wilkins and Rosalind Franklin working at King's College Hospital, London, used x-ray techniques to determine the structure of DNA; their work inspired the discovery of the double helix by James Watson and Francis Crick.