According to Watson-Crick complementary base pairing rules, which nitrogenous bases pair together across the DNA double helix?
Answer and explanation
Correct answer: A. Adenine pairs with Thymine (A-T), and Cytosine pairs with Guanine (C-G)
- Step 1: Hydrogen bonding requires specific base pairing: Adenine (A) pairs with Thymine (T) via 2 hydrogen bonds. Step 2. Cytosine (C) pairs with Guanine (G) via 3 hydrogen bonds. Answer: Adenine pairs with Thymine (A-T), and Cytosine pairs with Guanine (C-G). Why not the others: Uracil replaces Thymine in RNA, not DNA.
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