BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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purines, pyrimidines
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pyrimidines, purines
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dirings, monorings
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birings, unirings
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Detailed explanation-1: -Purines (adenine and guanine) are two-carbon nitrogen ring bases while pyrimidines (cytosine and thymine) are one-carbon nitrogen ring bases.
Detailed explanation-2: -Because of their structural similarity, we usually refer the nine-member double rings adenine and guanine as purines, and six-member single-ring thymine, uracil, and cytosine are pyrimidines.
Detailed explanation-3: -There are 5 nitrogenous bases that are classified as either purines or pyrimidines based on their chemical structure. The purine bases are adenine (A) and guanine (G). Cytosine (C), thymine (T), and uracil (U) are categorized as pyrimidines.
Detailed explanation-4: -Purines are heterocyclic amines consisting of a pyrimidine ring fused to a five-member ring with two nitrogen atoms. Adenine and guanine are the major purines found in nucleic acids (Figure 15.1.