Over evolutionary time, DNA replaced RNA as the primary molecule holding the code for genetic information because DNA is believed to be more chemically stable. Which attribute of DNA is the reason behind its chemical stability?
a) DNA lacks a free hydroxyl group on the 2?-carbon atom of its sugar.
b) Unlike RNA, DNA is usually double-stranded.
c) DNA does not usually form hairpin loops.
d) One of the two pyrimidines found in DNA does not involve uracil.
e) DNA contains thymines, which make it more chemically stable.
Ans: a) DNA lacks a free hydroxyl group on the 2?-carbon atom of its sugar.
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