In 1951, Erwin Chargaff was accumulating data on the molar ratios of nucleotides using DNA obtained from a variety of sources. Some of these data are provided in the following table:
Molar Ratios in DNA Preparations
Source A:G T:C A:T G:C Purine:pyrimidines
Ox 1.29 1.43 1.04 1.00 1.10
Human 1.56 1.75 1.00 1.00 1.0
Chicken 1.45 1.29 1.06 0.91 0.99
Salmon 1.43 1.43 1.02 1.02 1.02
Wheat 1.22 1.18 1.00 0.97 0.99
Yeast 1.67 1.92 1.03 1.20 1.0
Compare the molar ratios presented from each organism tested and between different organisms. What do they imply about the primary structure of DNA in different organisms?