What is the difference between purines and pyrimidines?

[NatePerrie]

I'm learning about DNA and RNA structures, but I'm a bit confused about purines and pyrimidines. Can someone explain how they differ in structure and function?

 

[DeeReich70]

Purines and pyrimidines are two types of nitrogenous bases found in nucleic acids (DNA and RNA).

• Purines have a double-ring structure and include adenine (A) and guanine (G).
• Pyrimidines have a single-ring structure and include cytosine (C), thymine (T) (in DNA), and uracil (U) (in RNA).

In short, purines are larger, double-ring bases, while pyrimidines are smaller, single-ring bases.