Polynucleotide chain of DNA contains

A DNA molecule is a polymer composed of long polynucleotide chains. Each individual nucleotide, the monomeric unit of these chains, consists of three distinct chemical components: a nitrogenous base, a five-carbon pentose sugar, and a phosphate group. In DNA specifically, the pentose sugar is deoxyribose, which distinguishes it from RNA that contains ribose sugar [3]. The nitrogenous bases in DNA include adenine, guanine, cytosine, and thymine [1]. These components are linked together where the phosphate group and the deoxyribose sugar form the structural backbone of the chain, while the nitrogenous bases are attached to the 1' carbon of the sugar [4]. Therefore, a polynucleotide chain of DNA is characterized by the presence of deoxyribose sugar alongside the nitrogenous base and phosphate group [2].

Sources

1. [1] https://www.genome.gov/genetics-glossary/Nucleotide
2. [3] https://www.khanacademy.org/science/ap-biology/gene-expression-and-regulation/dna-and-rna-structure/a/nucleic-acids
3. [4] https://www.ncbi.nlm.nih.gov/books/NBK26821/
4. [2] https://pmc.ncbi.nlm.nih.gov/articles/PMC6822018/