Which pair of nitrogen bases is wrongly matched?

Question

Accepted Answer

The correct option is 3:

In the study of molecular biology, nitrogenous bases are fundamental components of DNA and RNA, categorized into two main groups: purines and pyrimidines. Purines are characterized by their double-ring structure, while pyrimidines have a single-ring structure. Adenine (A) and Guanine (G) are both purines. Thymine (T), Cytosine (C), and Uracil (U) are all pyrimidines. The question asks to identify the pair of nitrogen bases that is *wrongly matched* with its category. Option 3, "Adenine, thymine....Purines," is incorrect because while Adenine is indeed a purine, Thymine is a pyrimidine. Therefore, matching Thymine with purines is a mismatch, making this the wrongly matched pair.

The incorrect option is 1:
Guanine and Adenine are both correctly classified as purines. Purines are nitrogenous bases that possess a double-ring structure, and both Guanine and Adenine fit this description.

The incorrect option is 2:
Thymine and Uracil are both correctly classified as pyrimidines. Pyrimidines are nitrogenous bases that possess a single-ring structure. Thymine is found in DNA, and Uracil replaces Thymine in RNA, and both are pyrimidines.

The incorrect option is 4:
Uracil and Cytosine are both correctly classified as pyrimidines. As mentioned, pyrimidines have a single-ring structure. Uracil is found in RNA, and Cytosine is found in both DNA and RNA, and both are indeed pyrimidines.