The race is now in earnest. How do the ""discoverers"" come to their conclusion about the structure of DNA? What information did they need?

They needed the general helix structure and the symmetry 15.

In some developing nations the percentage of the animal protein from fish in the diet can be as high as 25 percent.  about 85% of fish caught is used for human consumption.  the remainder is converted into fishmeal and fish oil. 

It is called the medulla oblongata or people usually call it medulla. it is the lower half of the brain stem continuous with the spinal cord.