BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Purines are single ring structures while pyrimidines are double ring structures.
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Pyrimidines are single ring structures while purines are double ring structures.
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Purines are composed of single bonds while pyrimidines are composed of double bonds.
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Pyrimidines are composed of single bonds while purines are composed of double bonds.
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Detailed explanation-1: -They are nitrogenous bases that make up the two different nucleotides in DNA and RNA. Purines (adenine and guanine) are two-carbon nitrogen ring bases while pyrimidines (cytosine and thymine) are one-carbon nitrogen ring bases.
Detailed explanation-2: -The purines (adenine and guanine) have a two-ringed structure consisting of a nine-membered molecule with four nitrogen atoms, as you can see in the two figures below. The pyrimidines (cytosine, uracil, and thymine) only have one single ring, which has just six members and two nitrogen atoms.
Detailed explanation-3: -There are two kinds of nitrogen-containing bases-purines and pyrimidines. Purines consist of a six-membered and a five-membered nitrogen-containing ring, fused together. Pyridmidines have only a six-membered nitrogen-containing ring.
Detailed explanation-4: -Purines have a double ringed aromatic structure. Adenine and guanine are examples of purines. Pyrimidines have a single ringed structure. Cytosine, thymine and uracil are examples of pyrimidine.