Question

What aspect of the sugar is unique to RNA?

1) It contains a double ring base.
2) It can form a 3' phosphodiester linkage.
3) It contains an OH group on the number 2' carbon of the pentose sugar.
4) It contains a pentose sugar.

Answer 1

The unique aspect of the sugar in RNA is the presence of an OH group on the 2' carbon of the pentose sugar ribose.

Step-by-step explanation:

The aspect of the sugar that is unique to RNA is that it contains an OH group on the number 2' carbon of the pentose sugar. In RNA, the sugar is ribose, which includes this 2'-OH group. In contrast, in DNA, the sugar is deoxyribose, and this same carbon only has a hydrogen atom attached. Consequently, DNA lacks the 2'-OH group, which is the characteristic that distinguishes RNA sugar from DNA sugar.