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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Double ringed structure
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Single ringed structure
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Detailed explanation-1: -The pyrimidines (cytosine, uracil, and thymine) only have one single ring, which has just six members and two nitrogen atoms. Because purines are essentially pyrimidines fused with a second ring, they are obviously bigger than pyrimidines.
Detailed explanation-2: -The pyrimidine ring is an aromatic heterocycle of two nitrogen and four carbon atoms. The numbering of atoms is done in a clockwise direction. Nitrogen atoms are present at positions 1 and 3. The sources of carbon 2 and nitrogen 3 are carbamoyl phosphate, while the rest of the ring is derived from aspartate.
Detailed explanation-3: -Answer and Explanation: Single-ring nitrogenous bases are called pyrimidines, while double-ringed structures are called purines. Pyrimidines include Cytosine, Thymine (only in DNA), and Uracil (only in RNA). Purines include Adenine and Guanine.
Detailed explanation-4: -The purines have a double ring structure with a six-membered ring fused to a five-membered ring. Pyrimidines are smaller in size; they have a single six-membered ring structure. The sugar is deoxyribose in DNA and ribose in RNA.