Читать книгу The Handy Psychology Answer Book - Lisa J. Cohen - Страница 190

By the mid-twentieth century, when James Watson (1928–) and Frances Crick (1916–2004) discovered the structure of deoxyribonucleic acid (DNA), the concept of genetic transmission of inherited traits was well established. It was widely accepted that an organism’s genetic code was contained in a specific molecule in the nucleus of a cell. This molecule had already been identified as deoxyribonucleic acid (DNA). What was unknown was the shape of that molecule. A trans-Atlantic race took place, in which the English scientific pair of Watson and Crick competed with American rivals to identify the molecular structure of the gene. Building on the previous work of Rosalind Franklin, Watson and Crick identified the shape of DNA as a double helix, a kind of twisting ladder. Additionally, they determined that the vertical bars of that ladder were made up of sugar and phosphate groups, while the rungs were formed from four nitrogenous bases: adenine, thymine, guanine, and cytosine. Together, these components form nucleotides, which are the building blocks of the DNA molecule. With this information, an enormous body of information opened up, ultimately allowing us to directly manipulate the genetic code for the first time in history. Of note, as a woman scientist in the 1950s, Rosalind Franklin received minimal recognition for her scientific contributions, an oversight which was only rectified long after she died.

The double helix shape of the DNA molecule was discovered by James Watson and Frances Crick with the help of Rosalind Franklin.