JEE Advanced levelOne or more correct optionsDifficulty 3 of 3bm163
A DNA duplex has one strand 5′-ATGCGC-3′ paired with its complementary strand. Select the correct statements. (A-T = 2 and G-C = 3 hydrogen bonds.)
AThe complementary strand reads 5′-GCGCAT-3′.
BThere are 16 hydrogen bonds between the strands.
CThe 3′ end of the complementary strand pairs with the 5′ end of the given strand.
DThere are 12 phosphodiester bonds in the duplex.
Answer: A, B, C
The reverse complement of ATGCGC is GCGCAT, with its 3-prime T paired to the 5-prime A of the given strand. Hydrogen bonds = 2+2+3+3+3+3=16. Each strand has 5 phosphodiester bonds, so 10 in all, not 12.