What bases are purines?
The two purine bases in humans are adenine and guanine.
- In DNA, they pair with their complementary pyrimidine bases, thymine and cytosine, respectively.
- In RNA, they pair with their complementary pyrimidine bases, uracil and cytosine, respectively.
Adenine (A) and guanine (G) look like this:
Thymine (T), uracil (U), and cytosine (C) look like this:
When we have a base pair, a purine base and its complementary pyrimidine base hydrogen-bond.
Example: AT Pair
Example: GC Pair