🦠microbiology review

Pyrimidines

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Pyrimidines are one of the two types of nitrogenous bases found in nucleic acids, characterized by a single six-membered ring structure. They include cytosine, thymine (in DNA), and uracil (in RNA).

5 Must Know Facts For Your Next Test

  1. Pyrimidines pair with purines through hydrogen bonding in the DNA double helix.
  2. In DNA, cytosine pairs with guanine and thymine pairs with adenine.
  3. In RNA, uracil replaces thymine and pairs with adenine.
  4. Pyrimidines are synthesized through a different metabolic pathway compared to purines.
  5. Mutations or alterations in pyrimidine metabolism can lead to genetic disorders.

Review Questions

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