Question

Choose the correct option with respect to RNA.

• A. Mutates at a faster rate
• B. Absence of free 2' OH in ribose
• C. Presence of thymine in place of uracil
• D. Is non-catalytic

Answer 1

The correct option is A Mutates at a faster rate

RNA is made up of ribonucleotides (Ribose sugar, Nitrogenous base, and phosphoric acid). The ribose (pentose sugar) has a hydroxyl group(-OH) at C'2. The nitrogenous bases present in the RNA are A(Adenine), U(Uracil), G(Guanine), C(Cytosine). Uracil is present instead of thymine, which is present in DNA.

RNA is catalytic in nature; ribozymes are group of catlytic RNAs. It mutates at a faster rate compared to DNA because it has a free hydroxyl group at C'2 which is more reactive and mutates faster. Secondly the presence of uracil, which lacks the methyl group (${\mathrm{CH}}_3$), makes it more reactive. Thirdly, it is mostly a single-stranded structure which makes it more susceptible to mutation .
Shown below is the structure of ribose sugar.