Biology 9700 · AS & A Level · Structure of nucleic acids and replication of DNA

Structure of nucleic acids and replication of DNA — practice question

Which statement concerning nitrogenous bases is correct?

  • AAdenine is a pyrimidine with a double ring structure.
  • BCytosine is a purine with a double ring structure.
  • CGuanine is a purine with a single ring structure.
  • DUracil is a pyrimidine with a single ring structure.

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