THE MOLECULAR BASIS OF INHERITANCE
STRUCTURE OF 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: -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.
Detailed explanation-4: -Pyrimidine: A nitrogenous base similar to benzene (a six-membered ring) and includes cytosine, thymine, and uracil as bases used for DNA or RNA.
Detailed explanation-5: -The major difference between purines and pyrimidines is their structure. Purines are constructed using nine-member molecules with four nitrogen atoms whereas pyrimidines are constructed using just 6 members molecules and two nitrogen atoms.