BIOLOGY
NUCLEIC ACIDS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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RNA can never be double-stranded; therefore, DNA is more stable
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The 2’-hydroxyl groups in RNA (absent in DNA) are directly involved in the hydrolysis of oligonucleotides
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Thymine forms more stable hydrogen bonds than uracil
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RNA does not have secondary structure
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Detailed explanation-1: -Due to its deoxyribose sugar, which contains one less oxygen-containing hydroxyl group, DNA is a more stable molecule than RNA, which is useful for a molecule which has the task of keeping genetic information safe. RNA, containing a ribose sugar, is more reactive than DNA and is not stable in alkaline conditions.
Detailed explanation-2: -While DNA contains deoxyribose, RNA contains ribose, characterised by the presence of the 2′-hydroxyl group on the pentose ring (Figure 5). This hydroxyl group make RNA less stable than DNA because it is more susceptible to hydrolysis.
Detailed explanation-3: -DNA is resistant to alkaline hydrolysis while RNA is not. RNA is susceptible to alkaline hydrolysis because the ribose sugar in RNA has a hydroxyl group at the 2’ position, which makes RNA chemically unstable compared to DNA (DNA has hydrogen at the 2’ position).
Detailed explanation-4: -Why does RNA have a 2?-hydroxyl group in a sugar while DNA does not? a. The presence of a hydroxyl group is impossible in the negatively charged DNA.
Detailed explanation-5: -DNA is more resistant than RNA to alkaline hydrolysis The presence of the vicinal 2’, 3’-hydroxyl groups on the ribose of RNA means that alkaline hydrolysis proceeds via the formation of an intermediate cyclic 2’, 3’-phosphonucleoside, whereas deoxyribose lacks the 2’-OH group required to form this intermediate.