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Question
All are important functional groups participating in H-bond formation EXCEPT:a. amino group of the cytosine, adenine and guanine.
b. the ring nitrogens at position 3 of pyrimidines and 1 of purines.
c. the electronegative oxygen atoms.
d. the electron density in the double bonds of the bases.
e. the carbonyl group at position 4 of uracil and thymine, position 2 of cytosine, and position 6 of guanine.
Answer
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