Q.What are the three structural differences between RNA and DNA ?

RNA and DNA differ in their sugar component, one of their four nitrogenous bases, and their overall strandedness.

Although both DNA and RNA are nucleic acids built from nucleotide subunits, they differ in three key structural respects. First, the pentose sugar in each nucleotide differs: DNA contains deoxyribose (which lacks a hydroxyl group at the 2' carbon), while RNA contains ribose (which retains the 2'-OH group) -- this difference gives the two molecules their names (deoxyribonucleic acid vs ribonucleic acid). Second, while both nucleic acids share the bases adenine, guanine and cytosine, DNA uses thymine as its fourth base, whereas RNA uses uracil in its place (uracil lacks the methyl group found on thymine). Third, in terms of overall architecture, DNA is characteristically a double-stranded molecule, forming the well-known double helix of two complementary, antiparallel stran …