Question

the nitrogen base pictured is adenine. is this nucleotide considered a purine or a pyrimidine?
purine
pyrimidine

Explanation:

Purines are nitrogen - containing bases with a double - ring (a six - membered and a five - membered ring) structure. Adenine, the nitrogen base in the given structure, has a double - ring structure. Pyrimidines have a single six - membered ring structure. So, adenine (the nucleotide's nitrogen base here) is a purine.

Answer:

purine