Chargaff's Rules & Base Pairing — NEET Biology
📚 Practice ConceptIf a double stranded DNA has 20 per cent of cytosine, calculate the per cent of adenine in the DNA.
Which of the above statements regarding DNA structure and base pairing are correct? S1: Guanine and Cytosine form three hydrogen bonds, making their interaction stronger than Adenine-Thymine pairing. S2: The complementary base pairing rules ensure that a purine always pairs with a pyrimidine, maintaining a uniform diameter of the DNA double helix. S3: Base stacking interactions between adjacent base pairs also contribute significantly to the stability of the double helical DNA structure. S4: The strength of hydrogen bonds between base pairs is the sole factor conferring stability to the DNA double helix. S5: In a double-stranded DNA molecule, the ratio of purines to pyrimidines is always one, according to Chargaff’s rule.
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