Mollisols primarily occur in the middle latitudes and are extensive in prairie regions such as the Great Plains of the US. Globally, they occupy ~7.0% of the ice-free land area. In the US, they are the most extensive soil order, accounting for ~21.5% of the land area. Mollisols are among some of the most important and productive agricultural soils in the world and are extensively used for this purpose. Mollisols are divided into 8 suborders: Albolls, Aquolls, Rendolls, Gelolls, Cryolls, Xerolls, Ustolls, and Udolls. Click here for more information about these suborders.
Simple Answer: James Watson and Francis Crick are credited with the first correct double-helix model of DNA structure published in 1953 in the journal Nature.
In 1953 James Watson and Francis Crick proposed the double-helix structure for the molecule, and by 1966 the genetic code (i.e. which amino acids were coded for by which sequences of DNA bases, and what the remaining codons meant,) had been completely worked out.s a result, Watson and Crick are largely recognized as discovering the structure of DNA for the first time, but it was really Watson, Crick and Franklin (among other, less influential, work by other scientists).