Answer:
Pyrimidines: adenosine, guanine, two rings structure
Purines: thymine, cytosine, one ring structure
Both sections: the rest
Explanation:
As you can see in the picture, both purines and pyrimidines have their characteristic structure.
Deoxyribose and phosphate group would be in middle because both types of nitrogen bases have to be able to make a nucleotide = nitrogen base + deoxyribose + phosphate group.
Hope this will help :)
