Nucleic Acids and Their Chemical Constituents

The major nucleic acid in the nucleus of cells is deoxyribonucleic add (or DNA). It contains the pentose sugar deoxyribose as one of its chemical constituents. DNA is now known to be the genetic material. Another type of nucleic acid, ribonucleic acid (or RNA), contains ribose instead of deoxyribose. Its main role is in the transmission of the genetic information from DNA into protein. 

DNA molecules are very large, much larger than proteins. RNA is more comparable to proteins in size. Complete hydrolysis of DNA (or RNA) by acid cleaves it into a mixture of nitrogenous bases, 2-deoxy-D-ribose (or D-ribose for RNA), and orthophosphate. There are two general types of nitrogenous bases in both DNA and RNA, pyrimidines and purines. 

Purines are derivatives of the fused-ring compound purine  

The numbering of the positions in the rings has been established by convention (IUPAC). 

The major pyrimidines found in DNA are thymine and cytosine in RNA, they are uracil and cytosine. These three pyrimidines differ in the types and positions of chemical groups attached to the ring. 

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NUCLEIC ACIDS AND THEIR CHEMICAL CONSTITUENTS NUCLEOSIDES NUCLEOTIDES... 

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