Model, one of two, made by Dorothy M. Crowfoot Hodgkin c.1967, to show the structure of 2 zinc pig insulin crystals at a resolution of 2.8A

In 1935, Dorothy M Crowfoot Hodgkin (1910-94), a British chemist and crystallographer, published the first X-ray photograph of insulin. Insulin is produced by the pancreas to break down sugars in the body. But Hodgkin and her team were unable to determine the 3-D structure of insulin until 1969, when this model was made. The larger metal balls in the model represent zinc, which was introduced chemically into the protein to decode the rest.