DNA Double Helix Structure Features — NEET Biology
📚 Practice ConceptThe salient features of the Double-helix structure of DNA are as follows:
Which of the following statements are correct regarding the structural features of the DNA double helix that contribute to its stability and overall architecture? S1: The two polynucleotide chains in a DNA molecule are coiled in a left-handed fashion. S2: Hydrogen bonds between complementary base pairs are crucial, with Adenine forming three H-bonds with Thymine and Guanine forming two H-bonds with Cytosine. S3: The backbone of the DNA double helix is formed by alternating sugar and phosphate groups, with the nitrogenous bases projecting inwards. S4: Stacking interactions between successive base pairs in the double helix, in addition to hydrogen bonds, confer significant stability. S5: The anti-parallel polarity of the two DNA strands means that if one strand has a 5'→3' orientation, the other has a 3'→5' orientation.
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