What Are Ribonucleic Acids RNA

Ribonucleic acids (RNA) are similar to deoxyribonucleic acids (DNA) in that they, too, consist of long, unbranched chains of nucleotides joined by phosphodiester groups between the 3 -hydroxyl of one pentose and the 5 -hydroxyl of the next. There are, however, three major differences in structure between RNA and DNA  

The pentose unit in RNA is jS-D-ribose rather than )3-2-deoxy-D-ribose. 

The pyrimidine bases in RNA are uracil and cytosine rather than thymine and cytosine. 

RNA is single stranded rather than double stranded. 

Following are structural formulas for the furanose form of D-ribose and for uracil  

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